android 去除 orx 相关依赖

Make top comment finding less strict.
Currently some comments start with /* instead of /**, which leads to import and package lines being included in README.md files.

android/build.gradle.kts

@@ -51,10 +51,10 @@ dependencies {
     implementation(libs.androidx.constraintlayout)
     implementation(libs.mapbox.maps)
     implementation(project(":math"))
-    implementation(project(":orx-triangulation"))
     implementation(libs.androidx.lifecycle.runtime.ktx)
     implementation(project(":icegps-common"))
     implementation(project(":icegps-shared"))
+    implementation(project(":icegps-triangulation"))
 
     testImplementation(libs.junit)
     androidTestImplementation(libs.ext.junit)

android/src/main/java/com/icegps/orx/ContoursManager.kt

@@ -0,0 +1,427 @@
+package com.icegps.orx
+
+import ColorBrewer2Type
+import android.content.Context
+import android.util.Log
+import colorBrewer2Palettes
+import com.icegps.math.geometry.Rectangle
+import com.icegps.math.geometry.Vector2D
+import com.icegps.math.geometry.Vector3D
+import com.icegps.orx.catmullrom.CatmullRomChain2
+import com.icegps.orx.ktx.area
+import com.icegps.orx.ktx.toColorInt
+import com.icegps.orx.ktx.toMapboxPoint
+import com.icegps.orx.ktx.toast
+import com.icegps.orx.marchingsquares.ShapeContour
+import com.icegps.orx.marchingsquares.findContours
+import com.icegps.shared.ktx.TAG
+import com.icegps.triangulation.DelaunayTriangulation
+import com.icegps.triangulation.Triangle
+import com.mapbox.geojson.Feature
+import com.mapbox.geojson.FeatureCollection
+import com.mapbox.geojson.LineString
+import com.mapbox.geojson.Polygon
+import com.mapbox.maps.MapView
+import com.mapbox.maps.Style
+import com.mapbox.maps.extension.style.expressions.generated.Expression
+import com.mapbox.maps.extension.style.layers.addLayer
+import com.mapbox.maps.extension.style.layers.generated.fillLayer
+import com.mapbox.maps.extension.style.layers.generated.lineLayer
+import com.mapbox.maps.extension.style.layers.properties.generated.LineCap
+import com.mapbox.maps.extension.style.layers.properties.generated.LineJoin
+import com.mapbox.maps.extension.style.sources.addSource
+import com.mapbox.maps.extension.style.sources.generated.geoJsonSource
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.async
+import kotlinx.coroutines.awaitAll
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import kotlin.math.max
+
+class ContoursManager(
+    private val context: Context,
+    private val mapView: MapView,
+    private val scope: CoroutineScope
+) {
+    private val sourceId: String = "contours-source-id-10"
+    private val layerId: String = "contours-layer-id-10"
+    private val fillSourceId: String = "contours-fill-source-id-10"
+    private val fillLayerId: String = "contours-fill-layer-id-10"
+    private val gridSourceId: String = "grid-polygon-source-id"
+    private val gridLayerId: String = "grid-polygon-layer-id"
+
+    private var contourSize: Int = 6
+    private var heightRange: ClosedFloatingPointRange<Double> = 0.0..100.0
+    private var cellSize: Double? = 10.0
+    val simplePalette = SimplePalette(
+        range = 0.0..100.0
+    )
+
+    private var colors = colorBrewer2Palettes(
+        numberOfColors = contourSize,
+        paletteType = ColorBrewer2Type.Any
+    ).first().colors.reversed()
+
+    private var points: List<Vector3D> = emptyList()
+
+    private val polylineManager = PolylineManager(mapView)
+
+    fun updateContourSize(contourSize: Int) {
+        this.contourSize = contourSize
+        colors = colorBrewer2Palettes(
+            numberOfColors = contourSize,
+            paletteType = ColorBrewer2Type.Any
+        ).first().colors.reversed()
+    }
+
+    fun updateCellSize(value: Double) {
+        cellSize = value
+    }
+
+    fun updatePoints(
+        points: List<Vector3D>,
+    ) {
+        this.points = points
+    }
+
+    fun updateHeightRange(
+        heightRange: ClosedFloatingPointRange<Double>? = null
+    ) {
+        if (heightRange == null) {
+            if (points.isEmpty()) {
+                return
+            }
+            val height = points.map { it.z }
+            val range = height.min()..height.max()
+            this.heightRange = range
+            simplePalette.setRange(range)
+        } else {
+            this.heightRange = heightRange
+            simplePalette.setRange(heightRange)
+        }
+    }
+
+    private var isGridVisible: Boolean = true
+    private var _gridModel = MutableStateFlow<GridModel?>(null)
+    val gridModel = _gridModel.asStateFlow()
+
+    fun setGridVisible(visible: Boolean) {
+        if (visible != isGridVisible) {
+            isGridVisible = visible
+            if (visible) {
+                _gridModel.value?.let { gridModel ->
+                    mapView.displayGridModel(
+                        grid = gridModel,
+                        sourceId = gridSourceId,
+                        layerId = gridLayerId,
+                        palette = simplePalette::palette
+                    )
+                }
+            } else {
+                mapView.mapboxMap.getStyle { style ->
+                    try {
+                        style.removeStyleLayer(gridLayerId)
+                    } catch (_: Exception) {
+                    }
+
+                    if (style.styleSourceExists(gridSourceId)) {
+                        style.removeStyleSource(gridSourceId)
+                    }
+                }
+            }
+        }
+    }
+
+    private var triangles: List<Triangle> = listOf()
+    private var isTriangleVisible: Boolean = true
+
+    fun setTriangleVisible(visible: Boolean) {
+        if (visible != isTriangleVisible) {
+            isTriangleVisible = visible
+            if (visible) {
+                polylineManager.update(
+                    triangles.map {
+                        listOf(it.x1, it.x2, it.x3)
+                            .map { Vector3D(it.x, it.y, it.z) }
+                    }
+                )
+            } else {
+                polylineManager.clearContours()
+            }
+        }
+    }
+
+    private var job: Job? = null
+
+    fun refresh() {
+        val points = points
+        if (points.size <= 3) {
+            context.toast("points size ${points.size}")
+            return
+        }
+        job?.cancel()
+        scope.launch {
+            mapView.mapboxMap.getStyle { style ->
+                val step = heightRange.endInclusive / contourSize
+                val zip = (0..contourSize).map { index ->
+                    heightRange.start + index * step
+                }.zipWithNext { a, b -> a..b }
+                val area = points.area
+                val triangulation = DelaunayTriangulation(points)
+                val triangles = triangulation.triangles()
+                val cellSize: Double = if (cellSize == null || cellSize!! < 0.1) {
+                    (max(triangulation.points.area.width, triangulation.points.area.height) / 50)
+                } else {
+                    cellSize!!
+                }
+                scope.launch {
+                    val gridModel = triangulationToGrid(
+                        delaunator = triangulation,
+                        cellSize = cellSize,
+                    )
+                    this@ContoursManager._gridModel.value = gridModel
+                    if (isGridVisible) mapView.displayGridModel(
+                        grid = gridModel,
+                        sourceId = gridSourceId,
+                        layerId = gridLayerId,
+                        palette = simplePalette::palette
+                    )
+                }
+                job = scope.launch(Dispatchers.Default) {
+                    val lineFeatures = mutableListOf<List<Feature>>()
+                    val features = zip.mapIndexed { index, range ->
+                        async {
+                            val contours = findContours(
+                                triangles = triangles,
+                                range = range,
+                                area = area,
+                                cellSize = cellSize
+                            )
+                            val color = colors[index].toColorInt()
+                            lineFeatures.add(contoursToLineFeatures(contours, color).flatten())
+                            contoursToPolygonFeatures(contours, color)
+                        }
+                    }.awaitAll()
+                    withContext(Dispatchers.Main) {
+                        if (false) setupLineLayer(
+                            style = style,
+                            sourceId = sourceId,
+                            layerId = layerId,
+                            features = lineFeatures.flatten()
+                        )
+                        setupFillLayer(
+                            style = style,
+                            sourceId = fillSourceId,
+                            layerId = fillLayerId,
+                            features = features.filterNotNull(),
+                        )
+                        Log.d(TAG, "refresh: 刷新完成")
+                    }
+                }
+            }
+        }
+    }
+
+    fun findContours(
+        triangles: List<Triangle>,
+        range: ClosedFloatingPointRange<Double>,
+        area: Rectangle,
+        cellSize: Double
+    ): List<ShapeContour> {
+        return findContours(
+            f = { v ->
+                val triangle = triangles.firstOrNull { triangle ->
+                    isPointInTriangle3D(v, listOf(triangle.x1, triangle.x2, triangle.x3))
+                }
+                (triangle?.let { triangle ->
+                    val interpolate = interpolateHeight(
+                        point = v,
+                        triangle = listOf(
+                            triangle.x1,
+                            triangle.x2,
+                            triangle.x3,
+                        )
+                    )
+                    if (interpolate.z in range) -1.0
+                    else 1.0
+                } ?: 1.0).also {
+                    Log.d(TAG, "findContours: ${v} -> ${it}")
+                }
+            },
+            area = area,
+            cellSize = cellSize,
+        )
+    }
+
+    private fun setupLineLayer(
+        style: Style,
+        sourceId: String,
+        layerId: String,
+        features: List<Feature>
+    ) {
+        style.removeStyleLayer(layerId)
+        style.removeStyleSource(sourceId)
+
+        val source = geoJsonSource(sourceId) {
+            featureCollection(FeatureCollection.fromFeatures(features))
+        }
+        style.addSource(source)
+
+        val layer = lineLayer(layerId, sourceId) {
+            lineColor(Expression.toColor(Expression.Companion.get("color"))) // 从属性获取颜色
+            lineWidth(1.0)
+            lineCap(LineCap.ROUND)
+            lineJoin(LineJoin.ROUND)
+            lineOpacity(0.8)
+        }
+        style.addLayer(layer)
+    }
+
+    private fun setupFillLayer(
+        style: Style,
+        sourceId: String,
+        layerId: String,
+        features: List<Feature>
+    ) {
+        style.removeStyleLayer(layerId)
+        style.removeStyleSource(sourceId)
+
+        val source = geoJsonSource(sourceId) {
+            featureCollection(FeatureCollection.fromFeatures(features))
+        }
+        style.addSource(source)
+
+        val layer = fillLayer(layerId, sourceId) {
+            fillColor(Expression.Companion.toColor(Expression.get("color"))) // 从属性获取颜色
+            fillOpacity(0.5)
+            fillAntialias(true)
+        }
+        style.addLayer(layer)
+    }
+
+    private var useCatmullRom: Boolean = true
+
+    fun setCatmullRom(enabled: Boolean) {
+        useCatmullRom = enabled
+    }
+
+    fun contoursToLineFeatures(contours: List<ShapeContour>, color: Int): List<List<Feature>> {
+        return contours.drop(1).map { contour ->
+            contour.segments.map { segment ->
+                LineString.fromLngLats(
+                    listOf(
+                        segment.start.toMapboxPoint(),
+                        segment.end.toMapboxPoint()
+                    )
+                )
+            }.map { lineString ->
+                Feature.fromGeometry(lineString).apply {
+                    // 将颜色Int转换为十六进制字符串
+                    addStringProperty("color", color.toHexColorString())
+                }
+            }
+        }
+    }
+
+    fun contoursToPolygonFeatures(contours: List<ShapeContour>, color: Int): Feature? {
+        val lists = contours.drop(0).filter { it.segments.isNotEmpty() }.map { contour ->
+            val start = contour.segments[0].start
+            listOf(start) + contour.segments.map { it.end }
+        }.map {
+            if (!useCatmullRom) return@map it
+            val cmr = CatmullRomChain2(it, 1.0, loop = true)
+            val contour = ShapeContour.fromPoints(cmr.positions(200), true)
+            val start = contour.segments[0].start
+            listOf(start) + contour.segments.map { it.end }
+        }.map { points -> points.map { it.toMapboxPoint() } }
+
+        if (lists.isEmpty()) {
+            Log.w(TAG, "contoursToPolygonFeatures: 没有有效的轮廓数据")
+            return null
+        }
+
+        val polygon = Polygon.fromLngLats(lists)
+        return Feature.fromGeometry(polygon).apply {
+            // 将颜色Int转换为十六进制字符串
+            addStringProperty("color", color.toHexColorString())
+        }
+    }
+
+    fun Int.toHexColorString(): String {
+        return String.format("#%06X", 0xFFFFFF and this)
+    }
+
+    fun clearContours() {
+        mapView.mapboxMap.getStyle { style ->
+            try {
+                style.removeStyleLayer(layerId)
+            } catch (_: Exception) {
+            }
+            try {
+                style.removeStyleSource(sourceId)
+            } catch (_: Exception) {
+            }
+        }
+    }
+}
+
+fun isPointInTriangle3D(point: Vector2D, triangle: List<Vector3D>): Boolean {
+    require(triangle.size == 3) { "三角形必须有3个顶点" }
+
+    val (v1, v2, v3) = triangle
+
+    // 计算重心坐标
+    val denominator = (v2.y - v3.y) * (v1.x - v3.x) + (v3.x - v2.x) * (v1.y - v3.y)
+    if (denominator == 0.0) return false // 退化三角形
+
+    val alpha = ((v2.y - v3.y) * (point.x - v3.x) + (v3.x - v2.x) * (point.y - v3.y)) / denominator
+    val beta = ((v3.y - v1.y) * (point.x - v3.x) + (v1.x - v3.x) * (point.y - v3.y)) / denominator
+    val gamma = 1.0 - alpha - beta
+
+    // 点在三角形内当且仅当所有重心坐标都在[0,1]范围内
+    return alpha >= 0 && beta >= 0 && gamma >= 0 &&
+            alpha <= 1 && beta <= 1 && gamma <= 1
+}
+
+/**
+ * 使用重心坐标计算点在三角形上的高度
+ *
+ * @param point 二维点 (x, y)
+ * @param triangle 三角形的三个顶点
+ * @return 三维点 (x, y, z)
+ */
+fun interpolateHeight(point: Vector2D, triangle: List<Vector3D>): Vector3D {
+    /**
+     * 计算点在三角形中的重心坐标
+     */
+    fun calculateBarycentricCoordinates(
+        point: Vector2D,
+        v1: Vector3D,
+        v2: Vector3D,
+        v3: Vector3D
+    ): Triple<Double, Double, Double> {
+        val denom = (v2.y - v3.y) * (v1.x - v3.x) + (v3.x - v2.x) * (v1.y - v3.y)
+
+        val alpha = ((v2.y - v3.y) * (point.x - v3.x) + (v3.x - v2.x) * (point.y - v3.y)) / denom
+        val beta = ((v3.y - v1.y) * (point.x - v3.x) + (v1.x - v3.x) * (point.y - v3.y)) / denom
+        val gamma = 1.0 - alpha - beta
+
+        return Triple(alpha, beta, gamma)
+    }
+
+    require(triangle.size == 3) { "三角形必须有3个顶点" }
+
+    val (v1, v2, v3) = triangle
+
+    // 计算重心坐标
+    val (alpha, beta, gamma) = calculateBarycentricCoordinates(point, v1, v2, v3)
+
+    // 使用重心坐标插值z值
+    val z = alpha * v1.z + beta * v2.z + gamma * v3.z
+
+    return Vector3D(point.x, point.y, z)
+}

android/src/main/java/com/icegps/orx/ControllableArrow.kt

@@ -0,0 +1,197 @@
+package com.icegps.orx
+
+import com.icegps.math.geometry.Angle
+import com.icegps.math.geometry.Vector2D
+import com.icegps.orx.ktx.toMapboxPoint
+import com.mapbox.geojson.Feature
+import com.mapbox.geojson.FeatureCollection
+import com.mapbox.geojson.LineString
+import com.mapbox.geojson.Point
+import com.mapbox.geojson.Polygon
+import com.mapbox.maps.MapView
+import com.mapbox.maps.Style
+import com.mapbox.maps.extension.style.expressions.generated.Expression
+import com.mapbox.maps.extension.style.layers.addLayer
+import com.mapbox.maps.extension.style.layers.generated.FillLayer
+import com.mapbox.maps.extension.style.layers.generated.LineLayer
+import com.mapbox.maps.extension.style.layers.properties.generated.LineCap
+import com.mapbox.maps.extension.style.layers.properties.generated.LineJoin
+import com.mapbox.maps.extension.style.sources.addSource
+import com.mapbox.maps.extension.style.sources.generated.geoJsonSource
+import kotlin.math.cos
+import kotlin.math.min
+import kotlin.math.sin
+
+/**
+ * 设置趋势箭头图层
+ */
+fun setupTrendLayer(
+    style: Style,
+    trendSourceId: String,
+    trendLayerId: String,
+    features: List<Feature>
+) {
+    val trendSource = geoJsonSource(trendSourceId) {
+        featureCollection(FeatureCollection.fromFeatures(features))
+    }
+
+    try {
+        style.removeStyleLayer(trendLayerId)
+    } catch (_: Exception) {
+    }
+
+    try {
+        style.removeStyleLayer("$trendLayerId-head")
+    } catch (_: Exception) {
+    }
+
+    if (style.styleSourceExists(trendSourceId)) {
+        style.removeStyleSource(trendSourceId)
+    }
+
+    style.addSource(trendSource)
+
+    val lineLayer = LineLayer(trendLayerId, trendSourceId).apply {
+        lineColor(Expression.toColor(Expression.get("color")))
+        lineWidth(4.0)
+        lineCap(LineCap.ROUND)
+        lineJoin(LineJoin.ROUND)
+    }
+    style.addLayer(lineLayer)
+
+    val headLayer = FillLayer("$trendLayerId-head", trendSourceId).apply {
+        fillColor(Expression.toColor(Expression.get("color")))
+    }
+    style.addLayer(headLayer)
+}
+
+fun MapView.displayControllableArrow(
+    grid: GridModel,
+    sourceId: String = "controllable-source-id-0",
+    layerId: String = "controllable-layer-id-0",
+    arrowScale: Double = 0.4,
+    angle: Angle,
+    onHeadArrowChange: (List<Point>) -> Unit
+) {
+    mapboxMap.getStyle { style ->
+        val centerX = (grid.minX + grid.maxX) / 2
+        val centerY = (grid.minY + grid.maxY) / 2
+
+        val regionWidth = grid.maxX - grid.minX
+        val regionHeight = grid.maxY - grid.minY
+        val arrowLength = min(regionWidth, regionHeight) * arrowScale * 1.0
+
+        val arrowDirectionRad = angle.radians
+        val endX = centerX + sin(arrowDirectionRad) * arrowLength
+        val endY = centerY + cos(arrowDirectionRad) * arrowLength
+
+        val arrowLine = LineString.fromLngLats(
+            listOf(
+                Vector2D(centerX, centerY),
+                Vector2D(endX, endY)
+            ).map { it.toMapboxPoint() }
+        )
+
+        val arrowFeature = Feature.fromGeometry(arrowLine)
+        arrowFeature.addStringProperty("color", "#0000FF")
+        arrowFeature.addStringProperty("type", "overall-trend")
+
+        // 创建箭头头部
+        val headSize = arrowLength * 0.2
+        val leftRad = arrowDirectionRad + Math.PI * 0.8
+        val rightRad = arrowDirectionRad - Math.PI * 0.8
+
+        val leftX = endX + sin(leftRad) * headSize
+        val leftY = endY + cos(leftRad) * headSize
+        val rightX = endX + sin(rightRad) * headSize
+        val rightY = endY + cos(rightRad) * headSize
+
+        val headRing = listOf(
+            Vector2D(endX, endY),
+            Vector2D(leftX, leftY),
+            Vector2D(rightX, rightY),
+            Vector2D(endX, endY)
+        ).map { it.toMapboxPoint() }
+        onHeadArrowChange(headRing)
+        val headPolygon = Polygon.fromLngLats(listOf(headRing))
+        val headFeature = Feature.fromGeometry(headPolygon)
+        headFeature.addStringProperty("color", "#0000FF")
+        headFeature.addStringProperty("type", "overall-trend")
+
+        val features = listOf(arrowFeature, headFeature)
+
+        // 设置图层
+        setupTrendLayer(style, sourceId, layerId, features)
+    }
+}
+
+fun calculateArrowData(
+    grid: GridModel,
+    angle: Angle,
+    arrowScale: Double = 0.4
+): ArrowData {
+    val centerX = (grid.minX + grid.maxX) / 2
+    val centerY = (grid.minY + grid.maxY) / 2
+
+    val regionWidth = grid.maxX - grid.minX
+    val regionHeight = grid.maxY - grid.minY
+    val arrowLength = min(regionWidth, regionHeight) * arrowScale * 1.0
+
+    val arrowDirectionRad = angle.radians
+    val endX = centerX + sin(arrowDirectionRad) * arrowLength
+    val endY = centerY + cos(arrowDirectionRad) * arrowLength
+
+    val arrowLine = listOf(
+        Vector2D(centerX, centerY),
+        Vector2D(endX, endY)
+    )
+
+    // 创建箭头头部
+    val headSize = arrowLength * 0.2
+    val leftRad = arrowDirectionRad + Math.PI * 0.8
+    val rightRad = arrowDirectionRad - Math.PI * 0.8
+
+    val leftX = endX + sin(leftRad) * headSize
+    val leftY = endY + cos(leftRad) * headSize
+    val rightX = endX + sin(rightRad) * headSize
+    val rightY = endY + cos(rightRad) * headSize
+
+    val headRing = listOf(
+        Vector2D(endX, endY),
+        Vector2D(leftX, leftY),
+        Vector2D(rightX, rightY),
+        Vector2D(endX, endY)
+    )
+    return ArrowData(
+        arrowLine = arrowLine,
+        headRing = headRing
+    )
+}
+
+data class ArrowData(
+    val arrowLine: List<Vector2D>,
+    val headRing: List<Vector2D>
+)
+
+fun MapView.displayControllableArrow(
+    sourceId: String = "controllable-source-id-0",
+    layerId: String = "controllable-layer-id-0",
+    arrowData: ArrowData
+) {
+    mapboxMap.getStyle { style ->
+        val (arrowLine, headRing) = arrowData
+        val arrowFeature = Feature.fromGeometry(LineString.fromLngLats(arrowLine.map { it.toMapboxPoint() }))
+        arrowFeature.addStringProperty("color", "#0000FF")
+        arrowFeature.addStringProperty("type", "overall-trend")
+
+        val headPolygon = Polygon.fromLngLats(listOf(headRing.map { it.toMapboxPoint() }))
+        val headFeature = Feature.fromGeometry(headPolygon)
+        headFeature.addStringProperty("color", "#0000FF")
+        headFeature.addStringProperty("type", "overall-trend")
+
+        val features = listOf(arrowFeature, headFeature)
+
+        // 设置图层
+        setupTrendLayer(style, sourceId, layerId, features)
+    }
+}

android/src/main/java/com/icegps/orx/CoordinateGenerator.kt

@@ -0,0 +1,53 @@
+package com.icegps.orx
+
+import com.icegps.math.geometry.Angle
+import com.icegps.math.geometry.Vector3D
+import com.icegps.math.geometry.degrees
+import kotlin.math.cos
+import kotlin.math.sin
+import kotlin.random.Random
+
+/**
+ * @author tabidachinokaze
+ * @date 2025/11/25
+ */
+fun coordinateGenerate(): List<Vector3D> {
+    val minX = -20.0
+    val maxX = 20.0
+    val minY = -20.0
+    val maxY = 20.0
+    val minZ = -20.0
+    val maxZ = 20.0
+    val x: () -> Double = { Random.nextDouble(minX, maxX) }
+    val y: () -> Double = { Random.nextDouble(minY, maxY) }
+    val z: () -> Double = { Random.nextDouble(minZ, maxZ) }
+    val dPoints = (0..60).map {
+        Vector3D(x(), y(), z())
+    }
+    return dPoints
+}
+
+fun coordinateGenerate1(): List<List<Vector3D>> {
+    /**
+     * 绕 Z 轴旋转指定角度（弧度）
+     */
+    fun Vector3D.rotateAroundZ(angle: Angle): Vector3D {
+        val cosAngle = cos(angle.radians)
+        val sinAngle = sin(angle.radians)
+
+        return Vector3D(
+            x = x * cosAngle - y * sinAngle,
+            y = x * sinAngle + y * cosAngle,
+            z = z
+        )
+    }
+
+    val center = Vector3D()
+    val direction = Vector3D(0.0, 1.0, -1.0)
+    return (0..360).step(10).map {
+        val nowDirection = direction.rotateAroundZ(it.degrees)
+        listOf(2, 6, 10).map {
+            center + nowDirection * it
+        }
+    }
+}

android/src/main/java/com/icegps/orx/DisplaySlopeResult.kt

@@ -0,0 +1,144 @@
+package com.icegps.orx
+
+import android.util.Log
+import com.icegps.math.geometry.Vector2D
+import com.icegps.orx.ktx.toMapboxPoint
+import com.mapbox.geojson.Feature
+import com.mapbox.geojson.FeatureCollection
+import com.mapbox.geojson.Polygon
+import com.mapbox.maps.MapView
+import com.mapbox.maps.Style
+import com.mapbox.maps.extension.style.expressions.generated.Expression
+import com.mapbox.maps.extension.style.layers.addLayer
+import com.mapbox.maps.extension.style.layers.generated.FillLayer
+import com.mapbox.maps.extension.style.layers.generated.LineLayer
+import com.mapbox.maps.extension.style.sources.addSource
+import com.mapbox.maps.extension.style.sources.generated.geoJsonSource
+
+/**
+ * @author tabidachinokaze
+ * @date 2025/11/26
+ */
+/**
+ * 绘制斜坡设计结果
+ */
+fun MapView.displaySlopeResult(
+    originalGrid: GridModel,
+    slopeResult: SlopeResult,
+    sourceId: String = "slope-result",
+    layerId: String = "slope-layer",
+    palette: (Double?) -> String,
+    showDesignHeight: Boolean
+) {
+    val elevationList = mutableListOf<Double>()
+    mapboxMap.getStyle { style ->
+        val features = mutableListOf<Feature>()
+        val designGrid = slopeResult.designSurface
+
+        // 对比测试，将绘制到原来图形的左边
+        // val minX = originalGrid.minX * 2 - originalGrid.maxX
+        val minX = originalGrid.minX
+        val maxY = originalGrid.maxY
+
+        val cellSize = originalGrid.cellSize
+
+        for (r in 0 until originalGrid.rows) {
+            for (c in 0 until originalGrid.cols) {
+                val originalElev = originalGrid.getValue(r, c) ?: continue
+                val designElev = designGrid.getValue(r, c) ?: continue
+                elevationList.add(designElev)
+
+                // 计算填挖高度
+                val heightDiff = designElev - originalElev
+
+                // 计算栅格边界
+                val x0 = minX + c * cellSize
+                val y0 = maxY - r * cellSize
+                val x1 = x0 + cellSize
+                val y1 = y0 - cellSize
+
+                // 1. 创建多边形要素（背景色）
+                val ring = listOf(
+                    Vector2D(x0, y0),
+                    Vector2D(x1, y0),
+                    Vector2D(x1, y1),
+                    Vector2D(x0, y1),
+                    Vector2D(x0, y0)
+                ).map { it.toMapboxPoint() }
+                val poly = Polygon.fromLngLats(listOf(ring))
+                val feature = Feature.fromGeometry(poly)
+
+                if (showDesignHeight) {
+                    // 显示设计高度，测试坡向是否正确，和高度是否计算正确
+                    feature.addStringProperty("color", palette(designElev))
+                } else {
+                    // 显示高差
+                    feature.addStringProperty("color", palette(heightDiff))
+                }
+                // 显示原始高度
+                // feature.addStringProperty("color", palette(originalElev))
+                features.add(feature)
+            }
+        }
+
+        Log.d("displayGridWithDirectionArrows", "对比区域的土方量计算: ${elevationList.sum()}, 平均值：${elevationList.average()}")
+
+        // 设置图层
+        setupEarthworkLayer(style, sourceId, layerId, features)
+    }
+}
+
+/**
+ * 完整的土方工程图层设置 - 修正版
+ */
+private fun setupEarthworkLayer(
+    style: Style,
+    sourceId: String,
+    layerId: String,
+    features: List<Feature>,
+) {
+    // 创建数据源
+    val source = geoJsonSource(sourceId) {
+        featureCollection(FeatureCollection.fromFeatures(features))
+    }
+
+    // 清理旧图层
+    try {
+        style.removeStyleLayer(layerId)
+    } catch (_: Exception) {
+    }
+    try {
+        style.removeStyleLayer("$layerId-arrow")
+    } catch (_: Exception) {
+    }
+    try {
+        style.removeStyleLayer("$layerId-outline")
+    } catch (_: Exception) {
+    }
+    try {
+        style.removeStyleLayer("$layerId-text")
+    } catch (_: Exception) {
+    }
+
+    if (style.styleSourceExists(sourceId)) {
+        style.removeStyleSource(sourceId)
+    }
+
+    // 添加数据源
+    style.addSource(source)
+
+    // 主填充图层
+    val fillLayer = FillLayer(layerId, sourceId).apply {
+        fillColor(Expression.toColor(Expression.get("color")))
+        fillOpacity(0.7)
+    }
+    style.addLayer(fillLayer)
+
+    // 边框图层
+    val outlineLayer = LineLayer("$layerId-outline", sourceId).apply {
+        lineColor("#333333")
+        lineWidth(1.0)
+        lineOpacity(0.5)
+    }
+    style.addLayer(outlineLayer)
+}

android/src/main/java/com/icegps/orx/EarthworkManager.kt

@@ -0,0 +1,438 @@
+package com.icegps.orx
+
+import android.graphics.PointF
+import android.util.Log
+import com.icegps.common.helper.GeoHelper
+import com.icegps.math.geometry.Angle
+import com.icegps.math.geometry.Vector2D
+import com.icegps.math.geometry.degrees
+import com.icegps.shared.ktx.TAG
+import com.mapbox.android.gestures.MoveGestureDetector
+import com.mapbox.geojson.Point
+import com.mapbox.maps.MapView
+import com.mapbox.maps.ScreenCoordinate
+import com.mapbox.maps.plugin.gestures.OnMoveListener
+import com.mapbox.maps.plugin.gestures.addOnMoveListener
+import com.mapbox.maps.plugin.gestures.removeOnMoveListener
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.combine
+import kotlinx.coroutines.flow.launchIn
+import kotlin.math.abs
+import kotlin.math.cos
+import kotlin.math.sin
+
+/**
+ * @author tabidachinokaze
+ * @date 2025/11/26
+ */
+object SlopeCalculator {
+    fun calculateSlope(
+        grid: GridModel,
+        slopeDirection: Double,
+        slopePercentage: Double,
+        baseHeightOffset: Double = 0.0
+    ): SlopeResult {
+        val centerX = (grid.minX + grid.maxX) / 2
+        val centerY = (grid.minY + grid.maxY) / 2
+
+        val elevations = grid.cells.filterNotNull()
+        val baseElevation = elevations.average() + baseHeightOffset
+
+        val basePoint = Triple(centerX, centerY, baseElevation)
+
+        val earthworkResult = EarthworkCalculator.calculateForSlopeDesign(
+            grid = grid,
+            basePoint = basePoint,
+            slope = slopePercentage,
+            aspect = slopeDirection
+        )
+
+        return SlopeResult(
+            slopeDirection = slopeDirection,
+            slopePercentage = slopePercentage,
+            baseHeightOffset = baseHeightOffset,
+            baseElevation = baseElevation,
+            earthworkResult = earthworkResult,
+            designSurface = generateSlopeDesignGrid(
+                grid = grid,
+                basePoint = basePoint,
+                slopePercentage = slopePercentage,
+                slopeDirection = slopeDirection
+            )
+        )
+    }
+
+
+    /**
+     * 生成斜坡设计面网格（用于可视化）
+     */
+    private fun generateSlopeDesignGrid(
+        grid: GridModel,
+        basePoint: Triple<Double, Double, Double>,
+        slopePercentage: Double,
+        slopeDirection: Double
+    ): GridModel {
+        val designCells = Array<Double?>(grid.rows * grid.cols) { null }
+        val (baseX, baseY, baseElev) = basePoint
+        val slopeRatio = slopePercentage / 100.0
+
+        for (r in 0 until grid.rows) {
+            for (c in 0 until grid.cols) {
+                if (grid.getValue(r, c) != null) {
+                    val cellX = grid.minX + (c + 0.5) * (grid.maxX - grid.minX) / grid.cols
+                    val cellY = grid.minY + (r + 0.5) * (grid.maxY - grid.minY) / grid.rows
+
+                    val designElev = calculateSlopeElevation(
+                        pointX = cellX,
+                        pointY = cellY,
+                        baseX = baseX,
+                        baseY = baseY,
+                        baseElev = baseElev,
+                        slopeRatio = slopeRatio,
+                        slopeDirection = slopeDirection
+                    )
+                    designCells[r * grid.cols + c] = designElev
+                }
+            }
+        }
+        return GridModel(
+            minX = grid.minX,
+            maxX = grid.maxX,
+            minY = grid.minY,
+            maxY = grid.maxY,
+            rows = grid.rows,
+            cols = grid.cols,
+            cellSize = grid.cellSize,
+            cells = designCells
+        )
+    }
+
+    /**
+     * 斜坡高程计算
+     */
+    fun calculateSlopeElevation(
+        pointX: Double,
+        pointY: Double,
+        baseX: Double,
+        baseY: Double,
+        baseElev: Double,
+        slopeRatio: Double,
+        slopeDirection: Double
+    ): Double {
+        val dx = (pointX - baseX) * cos(Math.toRadians(baseY))
+        val dy = (pointY - baseY)
+
+        val slopeRad = (slopeDirection.degrees - 90.degrees).normalized.radians
+
+        val projection = dx * cos(slopeRad) + dy * sin(slopeRad)
+        val heightDiff = projection * slopeRatio
+
+        return baseElev + heightDiff
+    }
+}
+
+/**
+ * 斜面设计
+ *
+ * @property slopeDirection 坡向 (度)
+ * @property slopePercentage 坡度 (%)
+ * @property baseHeightOffset 基准面高度偏移 (m)
+ * @property baseElevation 基准点高程 (m)
+ * @property earthworkResult 土方量结果
+ * @property designSurface 设计面网格（用于可视化）
+ */
+data class SlopeResult(
+    val slopeDirection: Double,
+    val slopePercentage: Double,
+    val baseHeightOffset: Double,
+    val baseElevation: Double,
+    val earthworkResult: EarthworkResult,
+    val designSurface: GridModel
+)
+
+object EarthworkCalculator {
+    /**
+     * @param grid 栅格网模型
+     * @param designElevation 设计高程
+     */
+    fun calculateForFlatDesign(
+        grid: GridModel,
+        designElevation: Double
+    ): EarthworkResult {
+        var cutVolume = 0.0
+        var fillVolume = 0.0
+        var cutArea = 0.0
+        var fillArea = 0.0
+        val cellArea = grid.cellSize * grid.cellSize
+
+        for (r in 0 until grid.rows) {
+            for (c in 0 until grid.cols) {
+                val originalElev = grid.getValue(r, c) ?: continue
+
+                val heightDiff = designElevation - originalElev
+
+                val volume = heightDiff * cellArea
+
+                if (volume > 0) {
+                    fillVolume += volume
+                    fillArea += cellArea
+                } else if (volume < 0) {
+                    cutVolume += abs(volume)
+                    cutArea += cellArea
+                }
+            }
+        }
+
+        return EarthworkResult(
+            cutVolume = cutVolume,
+            fillVolume = fillVolume,
+            netVolume = fillVolume - cutVolume,
+            cutArea = cutArea,
+            fillArea = fillArea,
+            totalArea = cutArea + fillArea
+        )
+    }
+
+    /**
+     * 计算斜面设计的土方量
+     */
+    fun calculateForSlopeDesign(
+        grid: GridModel,
+        basePoint: Triple<Double, Double, Double>,
+        slope: Double,
+        aspect: Double
+    ): EarthworkResult {
+        var cutVolume = 0.0
+        var fillVolume = 0.0
+        var cutArea = 0.0
+        var fillArea = 0.0
+        val cellArea = grid.cellSize * grid.cellSize
+
+        val (baseX, baseY, baseElev) = basePoint
+        val slopeRatio = slope / 100.0
+
+        for (r in 0 until grid.rows) {
+            for (c in 0 until grid.cols) {
+                val originalElev = grid.getValue(r, c) ?: continue
+
+                val cellX = grid.minX + (c + 0.5) * (grid.maxX - grid.minX) / grid.cols
+                val cellY = grid.minY + (r + 0.5) * (grid.maxY - grid.minY) / grid.rows
+
+                val designElev = SlopeCalculator.calculateSlopeElevation(
+                    pointX = cellX,
+                    pointY = cellY,
+                    baseX = baseX,
+                    baseY = baseY,
+                    baseElev = baseElev,
+                    slopeRatio = slopeRatio,
+                    slopeDirection = aspect
+                )
+
+                val heightElev = designElev - originalElev
+                val volume = heightElev * cellArea
+
+                if (volume > 0) {
+                    fillVolume += volume
+                    fillArea += cellArea
+                } else if (volume < 0) {
+                    cutVolume += abs(volume)
+                    cutArea += cellArea
+                }
+            }
+        }
+
+        return EarthworkResult(
+            cutVolume = cutVolume,
+            fillVolume = fillVolume,
+            netVolume = fillVolume - cutVolume,
+            cutArea = cutArea,
+            fillArea = fillArea,
+            totalArea = cutArea + fillArea
+        )
+    }
+}
+
+/**
+ * 土方量计算结果
+ * @property cutVolume 挖方量 (m³)
+ * @property fillVolume 填方量 (m³)
+ * @property netVolume 净土方量 (m³)
+ * @property cutArea 挖方面积 (m²)
+ * @property fillArea 填方面积 (m²)
+ * @property totalArea 总面积 (m²)
+ */
+data class EarthworkResult(
+    val cutVolume: Double,
+    val fillVolume: Double,
+    val netVolume: Double,
+    val cutArea: Double,
+    val fillArea: Double,
+    val totalArea: Double
+) {
+    override fun toString(): String {
+        return buildString {
+            appendLine("EarthworkResult")
+            appendLine("挖方: ${"%.1f".format(cutVolume)} m³")
+            appendLine("填方: ${"%.1f".format(fillVolume)} m³")
+            appendLine("净土方: ${"%.1f".format(netVolume)} m³")
+            appendLine("挖方面积: ${"%.1f".format(cutArea)} m²")
+            appendLine("填方面积: ${"%.1f".format(fillArea)} m²")
+            appendLine("总面积：${"%.1f".format(totalArea)} m²")
+        }
+    }
+}
+
+class EarthworkManager(
+    private val mapView: MapView,
+    private val scope: CoroutineScope
+) {
+    private val arrowSourceId: String = "controllable-source-id-0"
+    private val arrowLayerId: String = "controllable-layer-id-0"
+    private var listener: OnMoveListener? = null
+
+    private var gridModel = MutableStateFlow<GridModel?>(null)
+    private val arrowHead = MutableStateFlow(emptyList<Vector2D>())
+    private var arrowCenter = MutableStateFlow(Vector2D(0.0, 0.0))
+    private var arrowEnd = MutableStateFlow(Vector2D(0.0, 1.0))
+    private var _slopeDirection = MutableStateFlow(0.degrees)
+    val slopeDirection = _slopeDirection.asStateFlow()
+    private val _slopePercentage = MutableStateFlow(90.0)
+    val slopePercentage = _slopePercentage.asStateFlow()
+    private val _baseHeightOffset = MutableStateFlow(0.0)
+    val baseHeightOffset = _baseHeightOffset.asStateFlow()
+
+    init {
+        combine(
+            arrowCenter,
+            arrowEnd,
+            gridModel
+        ) { center, arrow, gridModel ->
+            gridModel?.let { gridModel ->
+                // _slopeDirection.value = angle
+                displayControllableArrow(gridModel, getSlopeDirection(arrow, center))
+            }
+        }.launchIn(scope)
+        combine(
+            _slopeDirection,
+            gridModel
+        ) { slopeDirection, gridModel ->
+            gridModel?.let {
+                displayControllableArrow(it, slopeDirection)
+            }
+        }.launchIn(scope)
+    }
+
+    private fun getSlopeDirection(
+        arrow: Vector2D,
+        center: Vector2D
+    ): Angle {
+        val direction = (arrow - center)
+        val atan2 = Angle.atan2(direction.x, direction.y, Vector2D.UP)
+        val angle = atan2.normalized
+        return angle
+    }
+
+    private fun displayControllableArrow(gridModel: GridModel, slopeDirection: Angle) {
+        val arrowData = calculateArrowData(
+            grid = gridModel,
+            angle = slopeDirection,
+        )
+        arrowHead.value = arrowData.headRing
+        mapView.displayControllableArrow(
+            sourceId = arrowSourceId,
+            layerId = arrowLayerId,
+            arrowData = arrowData,
+        )
+    }
+
+    fun Point.toVector2D(): Vector2D {
+        val geoHelper = GeoHelper.getSharedInstance()
+        val enu = geoHelper.wgs84ToENU(lon = longitude(), lat = latitude(), hgt = 0.0)
+        return Vector2D(enu.x, enu.y)
+    }
+
+    fun removeOnMoveListener() {
+        listener?.let(mapView.mapboxMap::removeOnMoveListener)
+        listener = null
+    }
+
+    fun setupOnMoveListener() {
+        listener = object : OnMoveListener {
+            private var beginning: Boolean = false
+            private var isDragging: Boolean = false
+            private fun getCoordinate(focalPoint: PointF): Point {
+                return mapView.mapboxMap.coordinateForPixel(ScreenCoordinate(focalPoint.x.toDouble(), focalPoint.y.toDouble()))
+            }
+
+            override fun onMove(detector: MoveGestureDetector): Boolean {
+                val focalPoint = detector.focalPoint
+                val point = mapView.mapboxMap
+                    .coordinateForPixel(ScreenCoordinate(focalPoint.x.toDouble(), focalPoint.y.toDouble()))
+                    .toVector2D()
+
+                val isPointInPolygon = RayCastingAlgorithm.isPointInPolygon(
+                    point = point,
+                    polygon = arrowHead.value
+                )
+
+                if (isPointInPolygon) {
+                    isDragging = true
+                }
+                if (isDragging) {
+                    arrowEnd.value = point
+                }
+                return isDragging
+            }
+
+            override fun onMoveBegin(detector: MoveGestureDetector) {
+                Log.d(TAG, "onMoveBegin: $detector")
+                beginning = true
+            }
+
+            override fun onMoveEnd(detector: MoveGestureDetector) {
+                Log.d(TAG, "onMoveEnd: $detector")
+                val point = getCoordinate(detector.focalPoint)
+                val arrow = point.toVector2D()
+                if (beginning && isDragging) {
+                    arrowEnd.value = arrow
+                    val center = arrowCenter.value
+                    _slopeDirection.value = getSlopeDirection(arrow, center)
+                }
+                Log.d(
+                    TAG,
+                    buildString {
+                        appendLine("onMoveEnd: ")
+                        appendLine("${point.longitude()}, ${point.latitude()}")
+                    }
+                )
+                isDragging = false
+                beginning = false
+            }
+        }.also(mapView.mapboxMap::addOnMoveListener)
+    }
+
+    fun updateGridModel(gridModel: GridModel) {
+        this.gridModel.value = gridModel
+        calculateArrowCenter(gridModel)
+    }
+
+    private fun calculateArrowCenter(gridModel: GridModel) {
+        val centerX = (gridModel.minX + gridModel.maxX) / 2
+        val centerY = (gridModel.minY + gridModel.maxY) / 2
+        arrowCenter.value = Vector2D(centerX, centerY)
+    }
+
+    fun updateSlopeDirection(angle: Angle) {
+        _slopeDirection.value = angle
+    }
+
+    fun updateSlopePercentage(value: Double) {
+        _slopePercentage.value = value
+    }
+
+    fun updateDesignHeight(value: Double) {
+        _baseHeightOffset.value = value
+    }
+}

android/src/main/java/com/icegps/orx/GridDisplay.kt

@@ -0,0 +1,83 @@
+package com.icegps.orx
+
+import com.icegps.common.helper.GeoHelper
+import com.icegps.math.geometry.Vector2D
+import com.mapbox.geojson.Feature
+import com.mapbox.geojson.FeatureCollection
+import com.mapbox.geojson.Point
+import com.mapbox.geojson.Polygon
+import com.mapbox.maps.MapView
+import com.mapbox.maps.extension.style.expressions.generated.Expression
+import com.mapbox.maps.extension.style.layers.addLayer
+import com.mapbox.maps.extension.style.layers.generated.FillLayer
+import com.mapbox.maps.extension.style.sources.addSource
+import com.mapbox.maps.extension.style.sources.generated.geoJsonSource
+
+/**
+ * @author tabidachinokaze
+ * @date 2025/11/25
+ */
+fun MapView.displayGridModel(
+    grid: GridModel,
+    sourceId: String,
+    layerId: String,
+    palette: (Double?) -> String,
+) {
+    val geoHelper = GeoHelper.getSharedInstance()
+    mapboxMap.getStyle { style ->
+        val polygonFeatures = mutableListOf<Feature>()
+
+        val minX = grid.minX
+        val maxY = grid.maxY
+        val cellSize = grid.cellSize
+
+        for (r in 0 until grid.rows) {
+            for (c in 0 until grid.cols) {
+                val idx = r * grid.cols + c
+                val v = grid.cells[idx] ?: continue
+
+                val x0 = minX + c * cellSize
+                val y0 = maxY - r * cellSize
+                val x1 = x0 + cellSize
+                val y1 = y0 - cellSize
+
+                val ring = listOf(
+                    Vector2D(x0, y0),
+                    Vector2D(x1, y0),
+                    Vector2D(x1, y1),
+                    Vector2D(x0, y1),
+                    Vector2D(x0, y0),
+                ).map {
+                    geoHelper.enuToWGS84Object(GeoHelper.ENU(it.x, it.y))
+                }.map {
+                    Point.fromLngLat(it.lon, it.lat)
+                }
+                val poly = Polygon.fromLngLats(listOf(ring))
+                val polyFeature = Feature.fromGeometry(poly)
+                polyFeature.addStringProperty("color", palette(v))
+                polyFeature.addNumberProperty("value", v ?: -9999.0)
+                polygonFeatures.add(polyFeature)
+            }
+        }
+
+        try {
+            style.removeStyleLayer(layerId)
+        } catch (_: Exception) {
+        }
+
+        if (style.styleSourceExists(sourceId)) {
+            style.removeStyleSource(sourceId)
+        }
+
+        val polygonSource = geoJsonSource(sourceId) {
+            featureCollection(FeatureCollection.fromFeatures(polygonFeatures))
+        }
+        style.addSource(polygonSource)
+
+        val fillLayer = FillLayer(layerId, sourceId).apply {
+            fillColor(Expression.toColor(Expression.get("color")))
+            fillOpacity(0.5)
+        }
+        style.addLayer(fillLayer)
+    }
+}

android/src/main/java/com/icegps/orx/GridModel.kt

@@ -0,0 +1,139 @@
+package com.icegps.orx
+
+import com.icegps.math.geometry.Vector2D
+import com.icegps.math.geometry.Vector3D
+import com.icegps.triangulation.DelaunayTriangulation
+import kotlin.math.absoluteValue
+import kotlin.math.ceil
+
+/**
+ * @author tabidachinokaze
+ * @date 2025/11/25
+ */
+data class GridModel(
+    val minX: Double,
+    val maxX: Double,
+    val minY: Double,
+    val maxY: Double,
+    val rows: Int,
+    val cols: Int,
+    val cellSize: Double,
+    val cells: Array<Double?>
+) {
+    fun getValue(row: Int, col: Int): Double? {
+        if (row !in 0..<rows || col < 0 || col >= cols) {
+            return null
+        }
+        return cells[row * cols + col]
+    }
+}
+
+fun triangulationToGrid(
+    delaunator: DelaunayTriangulation,
+    cellSize: Double = 50.0,
+    maxSidePixels: Int = 5000
+): GridModel {
+    fun pointInTriangle(pt: Vector2D, a: Vector3D, b: Vector3D, c: Vector3D): Boolean {
+        val v0x = c.x - a.x
+        val v0y = c.y - a.y
+        val v1x = b.x - a.x
+        val v1y = b.y - a.y
+        val v2x = pt.x - a.x
+        val v2y = pt.y - a.y
+
+        val dot00 = v0x * v0x + v0y * v0y
+        val dot01 = v0x * v1x + v0y * v1y
+        val dot02 = v0x * v2x + v0y * v2y
+        val dot11 = v1x * v1x + v1y * v1y
+        val dot12 = v1x * v2x + v1y * v2y
+
+        val denom = dot00 * dot11 - dot01 * dot01
+        if (denom == 0.0) return false
+        val invDenom = 1.0 / denom
+        val u = (dot11 * dot02 - dot01 * dot12) * invDenom
+        val v = (dot00 * dot12 - dot01 * dot02) * invDenom
+        return u >= 0 && v >= 0 && u + v <= 1
+    }
+
+    fun barycentricInterpolateLegacy(pt: Vector2D, a: Vector3D, b: Vector3D, c: Vector3D, values: DoubleArray): Double {
+        val area = { p1: Vector2D, p2: Vector3D, p3: Vector3D ->
+            ((p2.x - p1.x) * (p3.y - p1.y) - (p3.x - p1.x) * (p2.y - p1.y)).absoluteValue / 2.0
+        }
+        val area2 = { p1: Vector3D, p2: Vector3D, p3: Vector3D ->
+            ((p2.x - p1.x) * (p3.y - p1.y) - (p3.x - p1.x) * (p2.y - p1.y)).absoluteValue / 2.0
+        }
+        val areaTotal = area2(a, b, c)
+        if (areaTotal == 0.0) return values[0]
+        val wA = area(pt, b, c) / areaTotal
+        val wB = area(pt, c, a) / areaTotal
+        val wC = area(pt, a, b) / areaTotal
+        return values[0] * wA + values[1] * wB + values[2] * wC
+    }
+
+
+    val pts = delaunator.points
+    require(pts.isNotEmpty()) { "points empty" }
+
+    val x = pts.map { it.x }
+    val y = pts.map { it.y }
+    val minX = x.min()
+    val maxX = x.max()
+    val minY = y.min()
+    val maxY = y.max()
+
+    val width = maxX - minX
+    val height = maxY - minY
+
+    var cols = ceil(width / cellSize).toInt()
+    var rows = ceil(height / cellSize).toInt()
+
+    // 防止过大
+    if (cols > maxSidePixels) cols = maxSidePixels
+    if (rows > maxSidePixels) rows = maxSidePixels
+
+    val cells = Array<Double?>(rows * cols) { null }
+
+
+    val triangles = delaunator.triangles()
+
+    for (ti in 0 until triangles.size) {
+        val (a, b, c) = triangles[ti]
+
+        val tminX = minOf(a.x, b.x, c.x)
+        val tmaxX = maxOf(a.x, b.x, c.x)
+        val tminY = minOf(a.y, b.y, c.y)
+        val tmaxY = maxOf(a.y, b.y, c.y)
+
+        val colMin = ((tminX - minX) / cellSize).toInt().coerceIn(0, cols - 1)
+        val colMax = ((tmaxX - minX) / cellSize).toInt().coerceIn(0, cols - 1)
+        val rowMin = ((maxY - tmaxY) / cellSize).toInt().coerceIn(0, rows - 1)
+        val rowMax = ((maxY - tminY) / cellSize).toInt().coerceIn(0, rows - 1)
+
+        val triVertexVals = doubleArrayOf(a.z, b.z, c.z)
+
+        for (r in rowMin..rowMax) {
+            for (cIdx in colMin..colMax) {
+                val centerX = minX + (cIdx + 0.5) * cellSize
+                val centerY = maxY - (r + 0.5) * cellSize
+                val pt = Vector2D(centerX, centerY)
+                if (pointInTriangle(pt, a, b, c)) {
+                    val idx = r * cols + cIdx
+                    val valInterp = barycentricInterpolateLegacy(pt, a, b, c, triVertexVals)
+                    cells[idx] = valInterp
+                }
+            }
+        }
+    }
+
+    val grid = GridModel(
+        minX = minX,
+        minY = minY,
+        maxX = maxX,
+        maxY = maxY,
+        rows = rows,
+        cols = cols,
+        cellSize = cellSize,
+        cells = cells
+    )
+    return grid
+}

android/src/main/java/com/icegps/orx/MainActivity.kt

@@ -1,77 +1,220 @@
 package com.icegps.orx
 
 import android.os.Bundle
-import android.util.Log
 import androidx.activity.enableEdgeToEdge
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.view.ViewCompat
 import androidx.core.view.WindowInsetsCompat
-import androidx.lifecycle.ViewModel
-import androidx.lifecycle.viewModelScope
+import androidx.lifecycle.ViewModelProvider
+import androidx.lifecycle.lifecycleScope
+import com.google.android.material.slider.RangeSlider
+import com.google.android.material.slider.Slider
 import com.icegps.common.helper.GeoHelper
+import com.icegps.math.geometry.degrees
 import com.icegps.orx.databinding.ActivityMainBinding
-import com.icegps.shared.SharedHttpClient
-import com.icegps.shared.SharedJson
-import com.icegps.shared.api.OpenElevation
-import com.icegps.shared.api.OpenElevationApi
-import com.icegps.shared.ktx.TAG
 import com.icegps.shared.model.GeoPoint
 import com.mapbox.geojson.Point
+import com.mapbox.maps.CameraOptions
+import com.mapbox.maps.MapView
+import com.mapbox.maps.plugin.gestures.addOnMapClickListener
 import kotlinx.coroutines.flow.MutableStateFlow
-import kotlinx.coroutines.flow.catch
+import kotlinx.coroutines.flow.combine
+import kotlinx.coroutines.flow.filterNotNull
 import kotlinx.coroutines.flow.launchIn
-import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.onEach
-import kotlinx.coroutines.flow.update
-import org.openrndr.extra.triangulation.DelaunayTriangulation
-import org.openrndr.math.Vector2
-import org.openrndr.math.Vector3
 
 class MainActivity : AppCompatActivity() {
     private lateinit var binding: ActivityMainBinding
+    private lateinit var mapView: MapView
+    private val viewModel: MainViewModel by lazy {
+        ViewModelProvider(this)[MainViewModel::class.java]
+    }
+    private lateinit var contoursManager: ContoursManager
+    private lateinit var earthworkManager: EarthworkManager
+
+    init {
+        initGeoHelper()
+    }
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         enableEdgeToEdge()
         binding = ActivityMainBinding.inflate(layoutInflater)
+        mapView = binding.mapView
+        earthworkManager = EarthworkManager(mapView, lifecycleScope)
         setContentView(binding.root)
         ViewCompat.setOnApplyWindowInsetsListener(findViewById(R.id.main)) { v, insets ->
             val systemBars = insets.getInsets(WindowInsetsCompat.Type.systemBars())
             v.setPadding(systemBars.left, systemBars.top, systemBars.right, systemBars.bottom)
             insets
         }
+
+        mapView.mapboxMap.setCamera(
+            CameraOptions.Builder()
+                .center(Point.fromLngLat(home.longitude, home.latitude))
+                .pitch(0.0)
+                .zoom(18.0)
+                .bearing(0.0)
+                .build()
+        )
+
+        val points = coordinateGenerate()
+
+        // divider
+        contoursManager = ContoursManager(
+            context = this,
+            mapView = mapView,
+            scope = lifecycleScope
+        )
+        contoursManager.updateContourSize(6)
+        contoursManager.updatePoints(points)
+        val height = points.map { it.z }
+        val min = height.min()
+        val max = height.max()
+        contoursManager.updateHeightRange((min / 2)..max)
+        binding.heightRange.values = listOf(min.toFloat() / 2, max.toFloat())
+        binding.heightRange.valueFrom = min.toFloat()
+        binding.heightRange.valueTo = max.toFloat()
+        contoursManager.refresh()
+
+        binding.sliderTargetHeight.addOnSliderTouchListener(
+            object : Slider.OnSliderTouchListener {
+                override fun onStartTrackingTouch(p0: Slider) {
+                }
+
+                override fun onStopTrackingTouch(p0: Slider) {
+                    val present = p0.value / p0.valueTo
+                    // val targetHeight = ((valueRange.endInclusive - valueRange.start) * present) + valueRange.start
+
+                    // val contours = findContours(triangles, targetHeight)
+                    // contoursTest.clearContours()
+                    // if (false) contoursTest.updateContours(contours)
+                }
+            }
+        )
+
+        binding.heightRange.addOnSliderTouchListener(
+            object : RangeSlider.OnSliderTouchListener {
+                override fun onStartTrackingTouch(slider: RangeSlider) {
+                }
+
+                override fun onStopTrackingTouch(slider: RangeSlider) {
+                    contoursManager.updateHeightRange((slider.values.min().toDouble() - 1.0)..(slider.values.max().toDouble() + 1.0))
+                    contoursManager.refresh()
+                }
+            }
+        )
+
+        binding.switchGrid.setOnCheckedChangeListener { _, isChecked ->
+            contoursManager.setGridVisible(isChecked)
+        }
+        binding.switchTriangle.setOnCheckedChangeListener { _, isChecked ->
+            contoursManager.setTriangleVisible(isChecked)
+        }
+        binding.update.setOnClickListener {
+            contoursManager.refresh()
+        }
+        binding.cellSize.addOnSliderTouchListener(
+            object : Slider.OnSliderTouchListener {
+                override fun onStartTrackingTouch(slider: Slider) {
+                }
+
+                override fun onStopTrackingTouch(slider: Slider) {
+                    contoursManager.updateCellSize(slider.value.toDouble())
+                    contoursManager.refresh()
+                }
+            }
+        )
+        mapView.mapboxMap.addOnMapClickListener {
+            viewModel.addPoint(it)
+            true
+        }
+        binding.clearPoints.setOnClickListener {
+            viewModel.clearPoints()
+        }
+        binding.slopeDirection.addOnSliderTouchListener(
+            object : Slider.OnSliderTouchListener {
+                override fun onStartTrackingTouch(slider: Slider) {
+                }
+
+                override fun onStopTrackingTouch(slider: Slider) {
+                    earthworkManager.updateSlopeDirection(slider.value.degrees)
+                }
+            }
+        )
+        binding.slopePercentage.addOnSliderTouchListener(
+            object : Slider.OnSliderTouchListener {
+                override fun onStartTrackingTouch(slider: Slider) {
+                }
+
+                override fun onStopTrackingTouch(slider: Slider) {
+                    earthworkManager.updateSlopePercentage(slider.value.toDouble())
+                }
+            }
+        )
+        binding.designHeight.addOnSliderTouchListener(
+            object : Slider.OnSliderTouchListener {
+                override fun onStartTrackingTouch(slider: Slider) {
+                }
+
+                override fun onStopTrackingTouch(slider: Slider) {
+                    earthworkManager.updateDesignHeight(slider.value.toDouble())
+                }
+            }
+        )
+        binding.switchDesignSurface.setOnCheckedChangeListener { button, isChecked ->
+            showDesignHeight.value = isChecked
+        }
+        earthworkManager.setupOnMoveListener()
+        initData()
+    }
+
+    private val showDesignHeight = MutableStateFlow(false)
+
+    private fun initData() {
+        viewModel.points.onEach {
+            contoursManager.updatePoints(it)
+            contoursManager.updateHeightRange()
+            contoursManager.refresh()
+        }.launchIn(lifecycleScope)
+        contoursManager.gridModel.filterNotNull().onEach {
+            earthworkManager.updateGridModel(it)
+        }.launchIn(lifecycleScope)
+        earthworkManager.slopeDirection.onEach {
+            binding.slopeDirection.value = it.degrees.toFloat()
+        }.launchIn(lifecycleScope)
+        combine(
+            earthworkManager.slopeDirection,
+            earthworkManager.slopePercentage,
+            earthworkManager.baseHeightOffset,
+            contoursManager.gridModel,
+            showDesignHeight
+        ) { slopeDirection, slopePercentage, baseHeightOffset, gridModel, showDesignHeight ->
+            gridModel?.let { gridModel ->
+                val slopeResult: SlopeResult = SlopeCalculator.calculateSlope(
+                    grid = gridModel,
+                    slopeDirection = slopeDirection.degrees,
+                    slopePercentage = slopePercentage,
+                    baseHeightOffset = baseHeightOffset
+                )
+                mapView.displaySlopeResult(
+                    originalGrid = gridModel,
+                    slopeResult = slopeResult,
+                    palette = contoursManager.simplePalette::palette,
+                    showDesignHeight = showDesignHeight
+                )
+            }
+        }.launchIn(lifecycleScope)
     }
 }
 
-class MainViewModel : ViewModel() {
-    private val geoHelper = GeoHelper.getSharedInstance()
-    private val openElevation: OpenElevationApi = OpenElevation(SharedHttpClient(SharedJson()))
+val home = GeoPoint(114.476060, 22.771073, 30.897)
 
-    private val _points = MutableStateFlow<List<Point>>(emptyList())
-
-    init {
-        _points.map {
-            openElevation.lookup(it.map { GeoPoint(it.longitude(), it.latitude(), it.altitude()) })
-        }.catch {
-            Log.e(TAG, "高程请求失败", it)
-        }.map {
-            it.map {
-                val enu =
-                    geoHelper.wgs84ToENU(lon = it.longitude, lat = it.latitude, hgt = it.altitude)
-                Vector2(enu.x, enu.y)
-            }
-        }.onEach {
-            val triangulation = DelaunayTriangulation(it)
-            triangulation.triangles().map {
-                it.contour
-            }
-        }.launchIn(viewModelScope)
-    }
-
-    fun addPoint(point: Point) {
-        _points.update {
-            it.toMutableList().apply {
-                add(point)
-            }
-        }
-    }
+fun initGeoHelper(base: GeoPoint = home) {
+    val geoHelper = GeoHelper.getSharedInstance()
+    geoHelper.wgs84ToENU(
+        lon = base.longitude,
+        lat = base.latitude,
+        hgt = base.altitude
+    )
 }

android/src/main/java/com/icegps/orx/MainViewModel.kt

@@ -0,0 +1,59 @@
+package com.icegps.orx
+
+import android.app.Application
+import android.util.Log
+import androidx.lifecycle.AndroidViewModel
+import androidx.lifecycle.viewModelScope
+import com.icegps.common.helper.GeoHelper
+import com.icegps.math.geometry.Vector3D
+import com.icegps.orx.ktx.toast
+import com.icegps.shared.SharedHttpClient
+import com.icegps.shared.SharedJson
+import com.icegps.shared.api.OpenElevation
+import com.icegps.shared.api.OpenElevationApi
+import com.icegps.shared.ktx.TAG
+import com.icegps.shared.model.GeoPoint
+import com.mapbox.geojson.Point
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.catch
+import kotlinx.coroutines.flow.debounce
+import kotlinx.coroutines.flow.filter
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.stateIn
+import kotlinx.coroutines.flow.update
+
+class MainViewModel(private val context: Application) : AndroidViewModel(context) {
+    private val geoHelper = GeoHelper.Companion.getSharedInstance()
+    private val openElevation: OpenElevationApi = OpenElevation(SharedHttpClient(SharedJson()))
+
+    private val _points = MutableStateFlow<List<Point>>(emptyList())
+    val points = _points.filter { it.size > 3 }.debounce(1000).map {
+        openElevation.lookup(it.map { GeoPoint(it.longitude(), it.latitude(), it.altitude()) })
+    }.catch {
+        Log.e(TAG, "高程请求失败", it)
+        context.toast("高程请求失败")
+    }.map {
+        it.map {
+            val enu = geoHelper.wgs84ToENU(lon = it.longitude, lat = it.latitude, hgt = it.altitude)
+            Vector3D(enu.x, enu.y, enu.z)
+        }
+    }.stateIn(
+        scope = viewModelScope,
+        started = SharingStarted.Companion.Eagerly,
+        initialValue = emptyList()
+    )
+
+    fun addPoint(point: Point) {
+        context.toast("${point.longitude()}, ${point.latitude()}")
+        _points.update {
+            it.toMutableList().apply {
+                add(point)
+            }
+        }
+    }
+
+    fun clearPoints() {
+        _points.value = emptyList()
+    }
+}

android/src/main/java/com/icegps/orx/PolygonTest.kt

@@ -0,0 +1,123 @@
+package com.icegps.orx
+
+import android.graphics.Color
+import com.icegps.common.helper.GeoHelper
+import com.icegps.math.geometry.Vector3D
+import com.icegps.orx.ktx.toMapboxPoint
+import com.mapbox.geojson.Feature
+import com.mapbox.geojson.FeatureCollection
+import com.mapbox.geojson.LineString
+import com.mapbox.geojson.Polygon
+import com.mapbox.maps.MapView
+import com.mapbox.maps.Style
+import com.mapbox.maps.extension.style.layers.addLayer
+import com.mapbox.maps.extension.style.layers.generated.fillLayer
+import com.mapbox.maps.extension.style.layers.generated.lineLayer
+import com.mapbox.maps.extension.style.layers.properties.generated.LineCap
+import com.mapbox.maps.extension.style.layers.properties.generated.LineJoin
+import com.mapbox.maps.extension.style.sources.addSource
+import com.mapbox.maps.extension.style.sources.generated.geoJsonSource
+
+class PolygonTest(
+    private val mapView: MapView
+) {
+    private val geoHelper = GeoHelper.Companion.getSharedInstance()
+
+    private val contourSourceId = "contour-source-id-0"
+    private val contourLayerId = "contour-layer-id-0"
+
+    private val fillSourceId = "fill-source-id-0"
+    private val fillLayerId = "fill-layer-id-0"
+
+    fun update(
+        outer: List<Vector3D>,
+        inner: List<Vector3D>,
+        other: List<Vector3D>
+    ) {
+        val lineFeatures = mutableListOf<Feature>()
+        val fillFeatures = mutableListOf<Feature>()
+
+        val outerPoints = outer.map { it.toMapboxPoint() }
+        val innerPoints = inner.map { it.toMapboxPoint() }
+        val otherPoints = other.map { it.toMapboxPoint() }
+        val outerLine = LineString.fromLngLats(outerPoints)
+        Feature.fromGeometry(outerLine).also {
+            lineFeatures.add(it)
+        }
+        val innerLine = LineString.fromLngLats(innerPoints)
+        Feature.fromGeometry(innerLine).also {
+            lineFeatures.add(it)
+        }
+        Feature.fromGeometry(LineString.fromLngLats(otherPoints)).also {
+            lineFeatures.add(it)
+        }
+
+        //val polygon = Polygon.fromOuterInner(outerLine, innerLine)
+        val polygon = Polygon.fromLngLats(listOf(outerPoints, otherPoints, innerPoints))
+
+        mapView.mapboxMap.getStyle { style ->
+            if (false) setupLineLayer(
+                style = style,
+                sourceId = contourSourceId,
+                layerId = contourLayerId,
+                features = lineFeatures
+            )
+            setupFillLayer(
+                style = style,
+                sourceId = fillSourceId,
+                layerId = fillLayerId,
+                features = listOf(Feature.fromGeometry(polygon))
+            )
+        }
+    }
+
+    private fun setupLineLayer(
+        style: Style,
+        sourceId: String,
+        layerId: String,
+        features: List<Feature>
+    ) {
+        style.removeStyleLayer(layerId)
+        style.removeStyleSource(sourceId)
+
+        val source = geoJsonSource(sourceId) {
+            featureCollection(FeatureCollection.fromFeatures(features))
+        }
+        style.addSource(source)
+
+        val layer = lineLayer(layerId, sourceId) {
+            lineColor(Color.RED)
+            lineWidth(2.0)
+            lineCap(LineCap.Companion.ROUND)
+            lineJoin(LineJoin.Companion.ROUND)
+            lineOpacity(0.8)
+        }
+        style.addLayer(layer)
+    }
+
+    private fun setupFillLayer(
+        style: Style,
+        sourceId: String,
+        layerId: String,
+        features: List<Feature>
+    ) {
+        style.removeStyleLayer(layerId)
+        style.removeStyleSource(sourceId)
+
+        val source = geoJsonSource(sourceId) {
+            featureCollection(FeatureCollection.fromFeatures(features))
+        }
+        style.addSource(source)
+
+        val layer = fillLayer(fillLayerId, fillSourceId) {
+            fillColor(Color.YELLOW)
+            fillOpacity(0.3)
+            fillAntialias(true)
+        }
+        style.addLayer(layer)
+    }
+
+    fun clear() {
+
+    }
+}

android/src/main/java/com/icegps/orx/PolylineManager.kt

@@ -0,0 +1,121 @@
+package com.icegps.orx
+
+import android.graphics.Color
+import com.icegps.math.geometry.Line3D
+import com.icegps.math.geometry.Vector3D
+import com.icegps.orx.ktx.toMapboxPoint
+import com.mapbox.geojson.Feature
+import com.mapbox.geojson.FeatureCollection
+import com.mapbox.geojson.LineString
+import com.mapbox.maps.MapView
+import com.mapbox.maps.Style
+import com.mapbox.maps.extension.style.layers.addLayer
+import com.mapbox.maps.extension.style.layers.generated.lineLayer
+import com.mapbox.maps.extension.style.layers.properties.generated.LineCap
+import com.mapbox.maps.extension.style.layers.properties.generated.LineJoin
+import com.mapbox.maps.extension.style.sources.addSource
+import com.mapbox.maps.extension.style.sources.generated.geoJsonSource
+
+class PolylineManager(
+    private val mapView: MapView
+) {
+    private val sourceId: String = "polyline-source-id-0"
+    private val layerId: String = "polyline-layer-id-0"
+
+    fun update(
+        points: List<List<Vector3D>>
+    ) {
+        val lineStrings: List<List<Feature>> = points.map {
+            val lines = fromPoints(it, true)
+            lines.map {
+                LineString.fromLngLats(listOf(it.a.toMapboxPoint(), it.b.toMapboxPoint()))
+            }
+        }.map {
+            it.map { Feature.fromGeometry(it) }
+        }
+
+        mapView.mapboxMap.getStyle { style ->
+            setupLineLayer(
+                style = style,
+                sourceId = sourceId,
+                layerId = layerId,
+                features = lineStrings.flatten()
+            )
+        }
+    }
+
+    fun updateFeatures(
+        features: List<Feature>
+    ) {
+        mapView.mapboxMap.getStyle { style ->
+            setupLineLayer(
+                style = style,
+                sourceId = sourceId,
+                layerId = layerId,
+                features = features
+            )
+        }
+    }
+
+    private fun setupLineLayer(
+        style: Style,
+        sourceId: String,
+        layerId: String,
+        features: List<Feature>
+    ) {
+        style.removeStyleLayer(layerId)
+        style.removeStyleSource(sourceId)
+
+        val source = geoJsonSource(sourceId) {
+            featureCollection(FeatureCollection.fromFeatures(features))
+        }
+        style.addSource(source)
+
+        val layer = lineLayer(layerId, sourceId) {
+            lineColor(Color.RED)
+            lineWidth(2.0)
+            lineCap(LineCap.Companion.ROUND)
+            lineJoin(LineJoin.Companion.ROUND)
+            lineOpacity(0.8)
+        }
+        style.addLayer(layer)
+    }
+
+    fun clearContours() {
+        mapView.mapboxMap.getStyle { style ->
+            try {
+                style.removeStyleLayer(layerId)
+            } catch (_: Exception) {
+            }
+            try {
+                style.removeStyleSource(sourceId)
+            } catch (_: Exception) {
+            }
+        }
+    }
+}
+
+fun fromPoints(
+    points: List<Vector3D>,
+    closed: Boolean,
+) = if (points.isEmpty()) {
+    emptyList()
+} else {
+    if (!closed) {
+        (0 until points.size - 1).map {
+            Line3D(
+                points[it],
+                points[it + 1]
+            )
+        }
+    } else {
+        val d = (points.last() - points.first()).length
+        val usePoints = if (d > 1E-6) points else points.dropLast(1)
+        (usePoints.indices).map {
+            Line3D(
+                usePoints[it],
+                usePoints[(it + 1) % usePoints.size]
+            )
+        }
+    }
+}

android/src/main/java/com/icegps/orx/RayCastingAlgorithm.kt

@@ -0,0 +1,44 @@
+package com.icegps.orx
+
+import com.icegps.math.geometry.Vector2D
+import com.icegps.math.geometry.Vector3D
+import com.icegps.math.geometry.toVector2D
+
+/**
+ * @author tabidachinokaze
+ * @date 2025/11/26
+ */
+object RayCastingAlgorithm {
+    /**
+     * 使用射线法判断点是否在多边形内
+     * @param point 测试点
+     * @param polygon 多边形顶点列表
+     * @return true如果在多边形内
+     */
+    fun isPointInPolygon(point: Vector2D, polygon: List<Vector2D>): Boolean {
+        if (polygon.size < 3) return false
+
+        val x = point.x
+        val y = point.y
+        var inside = false
+
+        var j = polygon.size - 1
+        for (i in polygon.indices) {
+            val xi = polygon[i].x
+            val yi = polygon[i].y
+            val xj = polygon[j].x
+            val yj = polygon[j].y
+
+            val intersect = ((yi > y) != (yj > y)) && (x < (xj - xi) * (y - yi) / (yj - yi) + xi)
+
+            if (intersect) inside = !inside
+            j = i
+        }
+
+        return inside
+    }
+
+    fun isPointInPolygon(point: Vector3D, polygon: List<Vector3D>): Boolean {
+        return isPointInPolygon(point.toVector2D(), polygon.map { it.toVector2D() })
+    }
+}

android/src/main/java/com/icegps/orx/SimplePalette.kt

@@ -0,0 +1,123 @@
+package com.icegps.orx
+
+import android.util.Log
+
+/**
+ * @author tabidachinokaze
+ * @date 2025/11/25
+ */
+class SimplePalette(
+    private var range: ClosedFloatingPointRange<Double>
+) {
+    fun setRange(range: ClosedFloatingPointRange<Double>) {
+        this.range = range
+    }
+
+    private val colors: Map<Int, String>
+
+    init {
+        colors = generateTerrainColorMap()
+    }
+
+    fun palette(value: Double?): String {
+        if (value == null) return "#00000000"
+        val minH = range.start
+        val maxH = range.endInclusive
+        val normalized = ((value - minH) / (maxH - minH)).coerceIn(0.0, 1.0)
+        return colors[(normalized * 255).toInt()] ?: "#00000000"
+    }
+
+    fun palette1(value: Double?): String {
+        return if (value == null) "#00000000" else {
+            // 假设您已经知道高度范围，或者动态计算
+            val minH = range.start
+            val maxH = range.endInclusive
+            val normalized = ((value - minH) / (maxH - minH)).coerceIn(0.0, 1.0)
+            val alpha = (normalized * 255).toInt()
+            String.format("#%02X%02X%02X", alpha, 0, 0)
+        }.also {
+            Log.d("simplePalette", "$value -> $it")
+        }
+    }
+
+    fun generateGrayscaleColorMap2(): MutableMap<Int, String> {
+        val colorMap = mutableMapOf<Int, String>()
+
+        // 定义关键灰度点
+        val black = Color(0, 0, 0)       // 低地势 - 黑色
+        val darkGray = Color(64, 64, 64) // 过渡
+        val midGray = Color(128, 128, 128) // 中间
+        val lightGray = Color(192, 192, 192) // 过渡
+        val white = Color(255, 255, 255) // 高地势 - 白色
+
+        for (i in 0..255) {
+            val position = i / 255.0
+
+            val color = when {
+                position < 0.25 -> interpolateColor(black, darkGray, position / 0.25)
+                position < 0.5 -> interpolateColor(darkGray, midGray, (position - 0.25) / 0.25)
+                position < 0.75 -> interpolateColor(midGray, lightGray, (position - 0.5) / 0.25)
+                else -> interpolateColor(lightGray, white, (position - 0.75) / 0.25)
+            }
+            colorMap[i] = color.toHex()
+        }
+
+        return colorMap
+    }
+
+    fun generateGrayscaleColorMap(): MutableMap<Int, String> {
+        val colorMap = mutableMapOf<Int, String>()
+
+        for (i in 0..255) {
+            // 从黑色到白色的线性渐变
+            val grayValue = i
+            val color = Color(grayValue, grayValue, grayValue)
+            colorMap[i] = color.toHex()
+        }
+
+        return colorMap
+    }
+
+    fun generateTerrainColorMap(): MutableMap<Int, String> {
+        val colorMap = mutableMapOf<Int, String>()
+
+        // 定义关键颜色点
+        val blue = Color(0, 0, 255)    // 低地势 - 蓝色
+        val cyan = Color(0, 255, 255)  // 中间过渡
+        val green = Color(0, 255, 0)   // 中间过渡
+        val yellow = Color(255, 255, 0) // 中间过渡
+        val red = Color(255, 0, 0)     // 高地势 - 红色
+
+        for (i in 0..255) {
+            val position = i / 255.0
+
+            val color = when {
+                position < 0.25 -> interpolateColor(blue, cyan, position / 0.25)
+                position < 0.5 -> interpolateColor(cyan, green, (position - 0.25) / 0.25)
+                position < 0.75 -> interpolateColor(green, yellow, (position - 0.5) / 0.25)
+                else -> interpolateColor(yellow, red, (position - 0.75) / 0.25)
+            }
+            colorMap[i] = color.toHex()
+        }
+
+        return colorMap
+    }
+
+    fun interpolateColor(start: Color, end: Color, fraction: Double): Color {
+        val r = (start.red + (end.red - start.red) * fraction).toInt()
+        val g = (start.green + (end.green - start.green) * fraction).toInt()
+        val b = (start.blue + (end.blue - start.blue) * fraction).toInt()
+        return Color(r, g, b)
+    }
+
+    // Color类简化实现
+    class Color(val red: Int, val green: Int, val blue: Int) {
+        fun toArgb(): Int {
+            return (0xFF shl 24) or (red shl 16) or (green shl 8) or blue
+        }
+
+        fun toHex(): String {
+            return String.format("#%06X", toArgb() and 0xFFFFFF)
+        }
+    }
+}

android/src/main/java/com/icegps/orx/catmullrom/CatmullRom.kt

@@ -0,0 +1,135 @@
+package com.icegps.orx.catmullrom
+
+import com.icegps.math.geometry.Vector2D
+import com.icegps.orx.marchingsquares.Segment2D
+import com.icegps.orx.marchingsquares.ShapeContour
+import kotlin.math.min
+import kotlin.math.pow
+
+private const val almostZero = 0.00000001
+private const val almostOne = 0.99999999
+
+/**
+ * Creates a 2D Catmull-Rom spline curve.
+ *
+ * Can be represented as a segment drawn between [p1] and [p2],
+ * while [p0] and [p3] are used as control points.
+ *
+ * Under some circumstances alpha can have
+ * no perceptible effect, for example,
+ * when creating closed shapes with the vertices
+ * forming a regular 2D polygon.
+ *
+ * @param p0 The first control point.
+ * @param p1 The starting anchor point.
+ * @param p2 The ending anchor point.
+ * @param p3 The second control point.
+ * @param alpha The *tension* of the curve.
+ *      Use `0.0` for the uniform spline, `0.5` for the centripetal spline, `1.0` for the chordal spline.
+ */
+class CatmullRom2(val p0: Vector2D, val p1: Vector2D, val p2: Vector2D, val p3: Vector2D, val alpha: Double = 0.5) {
+    /** Value of t for p0. */
+    val t0: Double = 0.0
+
+    /** Value of t for p1. */
+    val t1: Double = calculateT(t0, p0, p1)
+
+    /** Value of t for p2. */
+    val t2: Double = calculateT(t1, p1, p2)
+
+    /** Value of t for p3. */
+    val t3: Double = calculateT(t2, p2, p3)
+
+    fun position(rt: Double): Vector2D {
+        val t = t1 + rt * (t2 - t1)
+        val a1 = p0 * ((t1 - t) / (t1 - t0)) + p1 * ((t - t0) / (t1 - t0))
+        val a2 = p1 * ((t2 - t) / (t2 - t1)) + p2 * ((t - t1) / (t2 - t1))
+        val a3 = p2 * ((t3 - t) / (t3 - t2)) + p3 * ((t - t2) / (t3 - t2))
+
+        val b1 = a1 * ((t2 - t) / (t2 - t0)) + a2 * ((t - t0) / (t2 - t0))
+        val b2 = a2 * ((t3 - t) / (t3 - t1)) + a3 * ((t - t1) / (t3 - t1))
+
+        val c = b1 * ((t2 - t) / (t2 - t1)) + b2 * ((t - t1) / (t2 - t1))
+        return c
+    }
+
+    private fun calculateT(t: Double, p0: Vector2D, p1: Vector2D): Double {
+        val a = (p1.x - p0.x).pow(2.0) + (p1.y - p0.y).pow(2.0)
+        val b = a.pow(0.5)
+        val c = b.pow(alpha)
+        return c + t
+    }
+}
+
+/**
+ * Calculates the 2D Catmull–Rom spline for a chain of points and returns the combined curve.
+ *
+ * For more details, see [CatmullRom2].
+ *
+ * @param points The [List] of 2D points where [CatmullRom2] is applied in groups of 4.
+ * @param alpha The *tension* of the curve.
+ *      Use `0.0` for the uniform spline, `0.5` for the centripetal spline, `1.0` for the chordal spline.
+ * @param loop Whether to connect the first and last point, such that it forms a closed shape.
+ */
+class CatmullRomChain2(points: List<Vector2D>, alpha: Double = 0.5, val loop: Boolean = false) {
+    val segments = if (!loop) {
+        val startPoints = points.take(2)
+        val endPoints = points.takeLast(2)
+        val mirrorStart =
+            startPoints.first() - (startPoints.last() - startPoints.first()).normalized
+        val mirrorEnd = endPoints.last() + (endPoints.last() - endPoints.first()).normalized
+
+        (listOf(mirrorStart) + points + listOf(mirrorEnd)).windowed(4, 1).map {
+            CatmullRom2(it[0], it[1], it[2], it[3], alpha)
+        }
+    } else {
+        val cleanPoints = if (loop && points.first().distanceTo(points.last()) <= 1.0E-6) {
+            points.dropLast(1)
+        } else {
+            points
+        }
+        (cleanPoints + cleanPoints.take(3)).windowed(4, 1).map {
+            CatmullRom2(it[0], it[1], it[2], it[3], alpha)
+        }
+    }
+
+    fun positions(steps: Int = segments.size * 4): List<Vector2D> {
+        return (0..steps).map {
+            position(it.toDouble() / steps)
+        }
+    }
+
+    fun position(rt: Double): Vector2D {
+        val st = if (loop) rt.mod(1.0) else rt.coerceIn(0.0, 1.0)
+        val segmentIndex = (min(almostOne, st) * segments.size).toInt()
+        val t = (min(almostOne, st) * segments.size) - segmentIndex
+        return segments[segmentIndex].position(t)
+    }
+}
+
+fun List<Vector2D>.catmullRom(alpha: Double = 0.5, closed: Boolean) = CatmullRomChain2(this, alpha, closed)
+
+/** Converts spline to a [Segment]. */
+fun CatmullRom2.toSegment(): Segment2D {
+    val d1a2 = (p1 - p0).length.pow(2 * alpha)
+    val d2a2 = (p2 - p1).length.pow(2 * alpha)
+    val d3a2 = (p3 - p2).length.pow(2 * alpha)
+    val d1a = (p1 - p0).length.pow(alpha)
+    val d2a = (p2 - p1).length.pow(alpha)
+    val d3a = (p3 - p2).length.pow(alpha)
+
+    val b0 = p1
+    val b1 = (p2 * d1a2 - p0 * d2a2 + p1 * (2 * d1a2 + 3 * d1a * d2a + d2a2)) / (3 * d1a * (d1a + d2a))
+    val b2 = (p1 * d3a2 - p3 * d2a2 + p2 * (2 * d3a2 + 3 * d3a * d2a + d2a2)) / (3 * d3a * (d3a + d2a))
+    val b3 = p2
+
+    return Segment2D(b0, b1, b2, b3)
+}
+
+
+/**
+ * Converts chain to a [ShapeContour].
+ */
+@Suppress("unused")
+fun CatmullRomChain2.toContour(): ShapeContour =
+    ShapeContour(segments.map { it.toSegment() }, this.loop)

android/src/main/java/com/icegps/orx/color/ColorRGBa.kt

@@ -0,0 +1,427 @@
+package com.icegps.orx.color
+
+import com.icegps.math.geometry.Vector3D
+import com.icegps.math.geometry.Vector4D
+import kotlinx.serialization.Serializable
+import kotlin.math.pow
+
+@Serializable
+enum class Linearity(val certainty: Int) {
+    /**
+     * Represents a linear color space.
+     *
+     * LINEAR typically signifies that the values in the color space are in a linear relationship,
+     * meaning there is no gamma correction or transformation applied to the data.
+     */
+    LINEAR(1),
+
+    /**
+     * Represents a standard RGB (sRGB) color space.
+     *
+     * SRGB typically refers to a non-linear color space with gamma correction applied,
+     * designed for consistent color representation across devices.
+     */
+    SRGB(1),
+    ;
+
+    fun leastCertain(other: Linearity): Linearity {
+        return if (this.certainty <= other.certainty) {
+            this
+        } else {
+            other
+        }
+    }
+
+    fun isEquivalent(other: Linearity): Boolean {
+        return this == other
+    }
+
+}
+
+/**
+ * Represents a color in the RGBA color space. Each component, including red, green, blue, and alpha (opacity),
+ * is represented as a `Double` in the range `[0.0, 1.0]`. The color can be defined in either linear or sRGB space,
+ * determined by the `linearity` property.
+ *
+ * This class provides a wide variety of utility functions for manipulating and converting colors, such as shading,
+ * opacity adjustment, and format transformations. It also includes methods for parsing colors from hexadecimal
+ * notation or vectors.
+ *
+ * @property r Red component of the color as a value between `0.0` and `1.0`.
+ * @property g Green component of the color as a value between `0.0` and `1.0`.
+ * @property b Blue component of the color as a value between `0.0` and `1.0`.
+ * @property alpha Alpha (opacity) component of the color as a value between `0.0` and `1.0`. Defaults to `1.0`.
+ * @property linearity Indicates whether the color is defined in linear or sRGB space. Defaults to [Linearity.LINEAR].
+ */
+@Serializable
+@Suppress("EqualsOrHashCode") // generated equals() is ok, only hashCode() needs to be overridden
+data class ColorRGBa(
+    val r: Double,
+    val g: Double,
+    val b: Double,
+    val alpha: Double = 1.0,
+    val linearity: Linearity = Linearity.LINEAR
+) {
+
+    enum class Component {
+        R,
+        G,
+        B
+    }
+
+    companion object {
+        /**
+         * Calculates a color from hexadecimal value. For values with transparency
+         * use the [String] variant of this function.
+         */
+        fun fromHex(hex: Int): ColorRGBa {
+            val r = hex and (0xff0000) shr 16
+            val g = hex and (0x00ff00) shr 8
+            val b = hex and (0x0000ff)
+            return ColorRGBa(r / 255.0, g / 255.0, b / 255.0, 1.0, Linearity.SRGB)
+        }
+
+        /**
+         * Calculates a color from hexadecimal notation, like in CSS.
+         *
+         * Supports the following formats
+         * * `RGB`
+         * * `RGBA`
+         * * `RRGGBB`
+         * * `RRGGBBAA`
+         *
+         * where every character is a valid hex digit between `0..f` (case-insensitive).
+         * Supports leading "#" or "0x".
+         */
+        fun fromHex(hex: String): ColorRGBa {
+            val pos = when {
+                hex.startsWith("#") -> 1
+                hex.startsWith("0x") -> 2
+                else -> 0
+            }
+
+            fun fromHex1(str: String, pos: Int): Double {
+                return 17 * str[pos].digitToInt(16) / 255.0
+            }
+
+            fun fromHex2(str: String, pos: Int): Double {
+                return (16 * str[pos].digitToInt(16) + str[pos + 1].digitToInt(16)) / 255.0
+            }
+            return when (hex.length - pos) {
+                3 -> ColorRGBa(fromHex1(hex, pos), fromHex1(hex, pos + 1), fromHex1(hex, pos + 2), 1.0, Linearity.SRGB)
+                4 -> ColorRGBa(
+                    fromHex1(hex, pos),
+                    fromHex1(hex, pos + 1),
+                    fromHex1(hex, pos + 2),
+                    fromHex1(hex, pos + 3),
+                    Linearity.SRGB
+                )
+
+                6 -> ColorRGBa(fromHex2(hex, pos), fromHex2(hex, pos + 2), fromHex2(hex, pos + 4), 1.0, Linearity.SRGB)
+                8 -> ColorRGBa(
+                    fromHex2(hex, pos),
+                    fromHex2(hex, pos + 2),
+                    fromHex2(hex, pos + 4),
+                    fromHex2(hex, pos + 6),
+                    Linearity.SRGB
+                )
+
+                else -> throw IllegalArgumentException("Invalid hex length/format for '$hex'")
+            }
+        }
+
+        /** @suppress */
+        val PINK = fromHex(0xffc0cb)
+
+        /** @suppress */
+        val BLACK = ColorRGBa(0.0, 0.0, 0.0, 1.0, Linearity.SRGB)
+
+        /** @suppress */
+        val WHITE = ColorRGBa(1.0, 1.0, 1.0, 1.0, Linearity.SRGB)
+
+        /** @suppress */
+        val RED = ColorRGBa(1.0, 0.0, 0.0, 1.0, Linearity.SRGB)
+
+        /** @suppress */
+        val BLUE = ColorRGBa(0.0, 0.0, 1.0, 1.0, Linearity.SRGB)
+
+        /** @suppress */
+        val GREEN = ColorRGBa(0.0, 1.0, 0.0, 1.0, Linearity.SRGB)
+
+        /** @suppress */
+        val YELLOW = ColorRGBa(1.0, 1.0, 0.0, 1.0, Linearity.SRGB)
+
+        /** @suppress */
+        val CYAN = ColorRGBa(0.0, 1.0, 1.0, 1.0, Linearity.SRGB)
+
+        /** @suppress */
+        val MAGENTA = ColorRGBa(1.0, 0.0, 1.0, 1.0, Linearity.SRGB)
+
+        /** @suppress */
+        val GRAY = ColorRGBa(0.5, 0.5, 0.5, 1.0, Linearity.SRGB)
+
+        /** @suppress */
+        val TRANSPARENT = ColorRGBa(0.0, 0.0, 0.0, 0.0, Linearity.LINEAR)
+
+        /**
+         * Create a ColorRGBa object from a [Vector3]
+         * @param vector input vector, `[x, y, z]` is mapped to `[r, g, b]`
+         * @param alpha optional alpha value, default is 1.0
+         */
+        fun fromVector(vector: Vector3D, alpha: Double = 1.0, linearity: Linearity = Linearity.LINEAR): ColorRGBa {
+            return ColorRGBa(vector.x, vector.y, vector.z, alpha, linearity)
+        }
+
+
+        /**
+         * Create a ColorRGBa object from a [Vector4]
+         * @param vector input vector, `[x, y, z, w]` is mapped to `[r, g, b, a]`
+         */
+        fun fromVector(vector: Vector4D, linearity: Linearity = Linearity.LINEAR): ColorRGBa {
+            return ColorRGBa(vector.x, vector.y, vector.z, vector.w, linearity)
+        }
+    }
+
+    @Deprecated("Legacy alpha parameter name", ReplaceWith("alpha"))
+    val a = alpha
+
+    /**
+     * Creates a copy of color with adjusted opacity
+     * @param factor a scaling factor used for the opacity
+     * @return A [ColorRGBa] with scaled opacity
+     * @see shade
+     */
+    fun opacify(factor: Double): ColorRGBa = ColorRGBa(r, g, b, alpha * factor, linearity)
+
+    /**
+     * Creates a copy of color with adjusted color
+     * @param factor a scaling factor used for the opacity
+     * @return A [ColorRGBa] with scaled colors
+     * @see opacify
+     */
+    fun shade(factor: Double): ColorRGBa = ColorRGBa(r * factor, g * factor, b * factor, alpha, linearity)
+
+    /**
+     * Copy of the color with all of its fields clamped to `[0, 1]`
+     */
+
+    @Deprecated("Use clip() instead", replaceWith = ReplaceWith("clip()"))
+    val saturated: ColorRGBa
+        get() = clip()
+
+    /**
+     * Copy of the color with all of its fields clamped to `[0, 1]`
+     */
+    fun clip(): ColorRGBa = copy(
+        r = r.coerceIn(0.0..1.0),
+        g = g.coerceIn(0.0..1.0),
+        b = b.coerceIn(0.0..1.0),
+        alpha = alpha.coerceIn(0.0..1.0)
+    )
+
+
+    /**
+     * Returns a new instance of [ColorRGBa] where the red, green, and blue components
+     * are multiplied by the alpha value of the original color. The alpha value and linearity
+     * remain unchanged.
+     *
+     * This computed property is commonly used for adjusting the color intensity based
+     * on its transparency.
+     */
+    val alphaMultiplied: ColorRGBa
+        get() = ColorRGBa(r * alpha, g * alpha, b * alpha, alpha, linearity)
+
+    /**
+     * The minimum value over `r`, `g`, `b`
+     * @see maxValue
+     */
+    val minValue get() = r.coerceAtMost(g).coerceAtMost(b)
+
+    /**
+     * The maximum value over `r`, `g`, `b`
+     * @see minValue
+     */
+    val maxValue get() = r.coerceAtLeast(g).coerceAtLeast(b)
+
+    /**
+     * calculate luminance value
+     * luminance value is according to <a>https://www.w3.org/TR/2008/REC-WCAG20-20081211/#relativeluminancedef</a>
+     */
+    val luminance: Double
+        get() = when (linearity) {
+            Linearity.SRGB -> toLinear().luminance
+            else -> 0.2126 * r + 0.7152 * g + 0.0722 * b
+        }
+
+    /**
+     * Converts this color to the specified linearity.
+     *
+     * @param linearity The target linearity to which the color should be converted.
+     *                  Supported values are [Linearity.SRGB] and [Linearity.LINEAR].
+     * @return A [ColorRGBa] instance in the specified linearity.
+     */
+    fun toLinearity(linearity: Linearity): ColorRGBa {
+        return when (linearity) {
+            Linearity.SRGB -> toSRGB()
+            Linearity.LINEAR -> toLinear()
+        }
+    }
+
+    /**
+     * calculate the contrast value between this color and the given color
+     * contrast value is accordingo to <a>// see http://www.w3.org/TR/2008/REC-WCAG20-20081211/#contrast-ratiodef</a>
+     */
+    fun getContrastRatio(other: ColorRGBa): Double {
+        val l1 = luminance
+        val l2 = other.luminance
+        return if (l1 > l2) (l1 + 0.05) / (l2 + 0.05) else (l2 + 0.05) / (l1 + 0.05)
+    }
+
+    fun toLinear(): ColorRGBa {
+        fun t(x: Double): Double {
+            return if (x <= 0.04045) x / 12.92 else ((x + 0.055) / (1 + 0.055)).pow(2.4)
+        }
+        return when (linearity) {
+            Linearity.SRGB -> ColorRGBa(t(r), t(g), t(b), alpha, Linearity.LINEAR)
+            else -> this
+        }
+    }
+
+    /**
+     * Convert to SRGB
+     * @see toLinear
+     */
+    fun toSRGB(): ColorRGBa {
+        fun t(x: Double): Double {
+            return if (x <= 0.0031308) 12.92 * x else (1 + 0.055) * x.pow(1.0 / 2.4) - 0.055
+        }
+        return when (linearity) {
+            Linearity.LINEAR -> ColorRGBa(t(r), t(g), t(b), alpha, Linearity.SRGB)
+            else -> this
+        }
+    }
+
+    fun toRGBa(): ColorRGBa = this
+
+    // This is here because the default hashing of enums on the JVM is not stable.
+    override fun hashCode(): Int {
+        var result = r.hashCode()
+        result = 31 * result + g.hashCode()
+        result = 31 * result + b.hashCode()
+        result = 31 * result + alpha.hashCode()
+        // here we overcome the unstable hash by using the ordinal value
+        result = 31 * result + linearity.ordinal.hashCode()
+        return result
+    }
+
+    fun plus(right: ColorRGBa) = copy(
+        r = r + right.r,
+        g = g + right.g,
+        b = b + right.b,
+        alpha = alpha + right.alpha
+    )
+
+    fun minus(right: ColorRGBa) = copy(
+        r = r - right.r,
+        g = g - right.g,
+        b = b - right.b,
+        alpha = alpha - right.alpha
+    )
+
+    fun times(scale: Double) = copy(r = r * scale, g = g * scale, b = b * scale, alpha = alpha * scale)
+
+    fun mix(other: ColorRGBa, factor: Double): ColorRGBa {
+        return mix(this, other, factor)
+    }
+
+    fun toVector4(): Vector4D = Vector4D(r, g, b, alpha)
+
+    /**
+     * Retrieves the color's RGBA component value based on the specified index:
+     * [index] should be 0 for red, 1 for green, 2 for blue, 3 for alpha.
+     * Other index values throw an [IndexOutOfBoundsException].
+     */
+    operator fun get(index: Int) = when (index) {
+        0 -> r
+        1 -> g
+        2 -> b
+        3 -> alpha
+        else -> throw IllegalArgumentException("unsupported index")
+    }
+}
+
+/**
+ * Weighted mix between two colors in the generic RGB color space.
+ * @param x the weighting of colors, a value 0.0 is equivalent to [left],
+ * 1.0 is equivalent to [right] and at 0.5 both colors contribute to the result equally
+ * @return a mix of [left] and [right] weighted by [x]
+ */
+fun mix(left: ColorRGBa, right: ColorRGBa, x: Double): ColorRGBa {
+    val sx = x.coerceIn(0.0, 1.0)
+
+    if (left.linearity.isEquivalent(right.linearity)) {
+        return ColorRGBa(
+            (1.0 - sx) * left.r + sx * right.r,
+            (1.0 - sx) * left.g + sx * right.g,
+            (1.0 - sx) * left.b + sx * right.b,
+            (1.0 - sx) * left.alpha + sx * right.alpha,
+            linearity = left.linearity.leastCertain(right.linearity)
+        )
+    } else {
+        return when (right.linearity) {
+            Linearity.LINEAR -> {
+                mix(left.toLinear(), right.toLinear(), x)
+            }
+
+            Linearity.SRGB -> {
+                mix(left.toSRGB(), right.toSRGB(), x)
+            }
+        }
+    }
+}
+
+/**
+ * Shorthand for calling [ColorRGBa].
+ * Specify only one value to obtain a shade of gray.
+ * @param r red in `[0,1]`
+ * @param g green in `[0,1]`
+ * @param b blue in `[0,1]`
+ * @param a alpha in `[0,1]`, defaults to `1.0`
+ */
+fun rgb(r: Double, g: Double, b: Double, a: Double = 1.0) = ColorRGBa(r, g, b, a, linearity = Linearity.LINEAR)
+
+/**
+ * Shorthand for calling [ColorRGBa].
+ * @param gray shade of gray in `[0,1]`
+ * @param a alpha in `[0,1]`, defaults to `1.0`
+ */
+fun rgb(gray: Double, a: Double = 1.0) = ColorRGBa(gray, gray, gray, a, linearity = Linearity.LINEAR)
+
+/**
+ * Create a color in RGBa space
+ * This function is a shorthand for using the ColorRGBa constructor
+ * @param r red in `[0,1]`
+ * @param g green in `[0,1]`
+ * @param b blue in `[0,1]`
+ * @param a alpha in `[0,1]`
+ */
+@Deprecated("Use rgb(r, g, b, a)", ReplaceWith("rgb(r, g, b, a)"), DeprecationLevel.WARNING)
+fun rgba(r: Double, g: Double, b: Double, a: Double) = ColorRGBa(r, g, b, a, linearity = Linearity.LINEAR)
+
+/**
+ * Shorthand for calling [ColorRGBa.fromHex].
+ * Creates a [ColorRGBa] with [Linearity.SRGB] from a hex string.
+ * @param hex string encoded hex value, for example `"ffc0cd"`
+ */
+fun rgb(hex: String) = ColorRGBa.fromHex(hex)
+
+/**
+ * Converts RGB integer color values into a ColorRGBa object with sRGB linearity.
+ *
+ * @param red The red component of the color, in the range 0-255.
+ * @param green The green component of the color, in the range 0-255.
+ * @param blue The blue component of the color, in the range 0-255.
+ * @param alpha The alpha (transparency) component of the color, in the range 0-255. Default value is 255 (fully opaque).
+ */
+fun rgb(red: Int, green: Int, blue: Int, alpha: Int = 255) =
+    ColorRGBa(red / 255.0, green / 255.0, blue / 255.0, alpha / 255.0, Linearity.SRGB)

android/src/main/java/com/icegps/orx/ktx/ColorRGBa.kt

@@ -0,0 +1,23 @@
+package com.icegps.orx.ktx
+
+import com.icegps.orx.color.ColorRGBa
+
+/**
+ * @author tabidachinokaze
+ * @date 2025/11/25
+ */
+fun ColorRGBa.toColorInt(): Int {
+    val clampedR = r.coerceIn(0.0, 1.0)
+    val clampedG = g.coerceIn(0.0, 1.0)
+    val clampedB = b.coerceIn(0.0, 1.0)
+    val clampedAlpha = alpha.coerceIn(0.0, 1.0)
+
+    return ((clampedAlpha * 255).toInt() shl 24) or
+            ((clampedR * 255).toInt() shl 16) or
+            ((clampedG * 255).toInt() shl 8) or
+            ((clampedB * 255).toInt())
+}
+
+fun ColorRGBa.toColorHex(): String {
+    return String.format("#%06X", 0xFFFFFF and toColorInt())
+}

android/src/main/java/com/icegps/orx/ktx/Context.kt

@@ -0,0 +1,12 @@
+package com.icegps.orx.ktx
+
+import android.content.Context
+import android.widget.Toast
+
+/**
+ * @author tabidachinokaze
+ * @date 2025/11/25
+ */
+fun Context.toast(text: String, duration: Int = Toast.LENGTH_SHORT) {
+    Toast.makeText(this, text, duration).show()
+}

android/src/main/java/com/icegps/orx/ktx/Vector2D.kt

@@ -0,0 +1,24 @@
+package com.icegps.orx.ktx
+
+import com.icegps.common.helper.GeoHelper
+import com.icegps.math.geometry.Vector2D
+import com.mapbox.geojson.Point
+
+/**
+ * @author tabidachinokaze
+ * @date 2025/11/26
+ */
+fun Vector2D.toMapboxPoint(): Point {
+    val geoHelper = GeoHelper.getSharedInstance()
+    val wgs84 = geoHelper.enuToWGS84Object(GeoHelper.ENU(x = x, y = y))
+    return Point.fromLngLat(wgs84.lon, wgs84.lat)
+}
+
+/**
+ * Interpolates between the current vector and the given vector `o` by the specified mixing factor.
+ *
+ * @param o The target vector to interpolate towards.
+ * @param mix A mixing factor between 0 and 1 where `0` results in the current vector and `1` results in the vector `o`.
+ * @return A new vector that is the result of the interpolation.
+ */
+fun Vector2D.mix(o: Vector2D, mix: Double): Vector2D = this * (1 - mix) + o * mix

android/src/main/java/com/icegps/orx/ktx/Vector3D.kt

@@ -0,0 +1,32 @@
+package com.icegps.orx.ktx
+
+import com.icegps.common.helper.GeoHelper
+import com.icegps.math.geometry.Rectangle
+import com.icegps.math.geometry.Vector3D
+import com.mapbox.geojson.Point
+
+fun Vector3D.niceStr(): String {
+    return "[$x, $y, $z]".format(this)
+}
+
+fun List<Vector3D>.niceStr(): String {
+    return joinToString(", ", "[", "]") {
+        it.niceStr()
+    }
+}
+
+fun Vector3D.toMapboxPoint(): Point {
+    val geoHelper = GeoHelper.getSharedInstance()
+    return geoHelper.enuToWGS84Object(GeoHelper.ENU(x, y, z)).run {
+        Point.fromLngLat(lon, lat, hgt)
+    }
+}
+
+val List<Vector3D>.area: Rectangle
+    get() {
+        val minX = minOf { it.x }
+        val maxX = maxOf { it.x }
+        val minY = minOf { it.y }
+        val maxY = maxOf { it.y }
+        return Rectangle(x = minX, y = minY, width = maxX - minX, height = maxY - minY)
+    }

android/src/main/java/com/icegps/orx/marchingsquares/MarchingSquares.kt

@@ -0,0 +1,219 @@
+package com.icegps.orx.marchingsquares
+
+import com.icegps.math.geometry.Rectangle
+import com.icegps.math.geometry.Vector2D
+import com.icegps.math.geometry.Vector2I
+import com.icegps.orx.ktx.mix
+import kotlin.math.max
+import kotlin.math.min
+
+private const val closeEpsilon = 1E-6
+
+data class Segment2D(
+    val start: Vector2D,
+    val control: List<Vector2D>,
+    val end: Vector2D,
+    val corner: Boolean = false
+)
+
+fun Segment2D(start: Vector2D, end: Vector2D, corner: Boolean = true) =
+    Segment2D(start, emptyList(), end, corner)
+
+fun Segment2D(start: Vector2D, c0: Vector2D, c1: Vector2D, end: Vector2D, corner: Boolean = true) =
+    Segment2D(start, listOf(c0, c1), end, corner)
+
+data class ShapeContour(
+    val segments: List<Segment2D>,
+    val closed: Boolean,
+) {
+    companion object {
+        val EMPTY = ShapeContour(
+            segments = emptyList(),
+            closed = false,
+        )
+
+        /**
+         * Creates a ShapeContour from a list of points, specifying whether the contour is closed and its y-axis polarity.
+         *
+         * @param points A list of points (Vector2) defining the vertices of the contour.
+         * @param closed Boolean indicating whether the contour should be closed (forms a loop).
+         * @return A ShapeContour object representing the resulting contour.
+         */
+        fun fromPoints(
+            points: List<Vector2D>,
+            closed: Boolean,
+        ): ShapeContour = if (points.isEmpty()) {
+            EMPTY
+        } else {
+            if (!closed) {
+                ShapeContour((0 until points.size - 1).map {
+                    Segment2D(
+                        points[it],
+                        points[it + 1]
+                    )
+                }, false)
+            } else {
+                val d = (points.last() - points.first()).lengthSquared
+                val usePoints = if (d > closeEpsilon) points else points.dropLast(1)
+                ShapeContour((usePoints.indices).map {
+                    Segment2D(
+                        usePoints[it],
+                        usePoints[(it + 1) % usePoints.size]
+                    )
+                }, true)
+            }
+        }
+    }
+}
+
+data class LineSegment(val start: Vector2D, val end: Vector2D)
+
+/**
+ * Find contours for a function [f] using the marching squares algorithm. A contour is found when f(x) crosses zero.
+ * @param f the function
+ * @param area a rectangular area in which the function should be evaluated
+ * @param cellSize the size of the cells, smaller size gives higher resolution
+ * @param useInterpolation intersection points will be interpolated if true, default true
+ * @return a list of [ShapeContour] instances
+ */
+fun findContours(
+    f: (Vector2D) -> Double,
+    area: Rectangle,
+    cellSize: Double,
+    useInterpolation: Boolean = true
+): List<ShapeContour> {
+    val segments = mutableListOf<LineSegment>()
+    val values = mutableMapOf<Vector2I, Double>()
+    val segmentsMap = mutableMapOf<Vector2D, MutableList<LineSegment>>()
+
+    for (y in 0 until (area.height / cellSize).toInt()) {
+        for (x in 0 until (area.width / cellSize).toInt()) {
+            values[Vector2I(x, y)] = f(Vector2D(x * cellSize + area.x, y * cellSize + area.y))
+        }
+    }
+
+    val zero = 0.0
+    for (y in 0 until (area.height / cellSize).toInt()) {
+        for (x in 0 until (area.width / cellSize).toInt()) {
+
+            // Here we check if we are at a right or top border. This is to ensure we create closed contours
+            // later on in the process.
+            val v00 = if (x == 0 || y == 0) zero else (values[Vector2I(x, y)] ?: zero)
+            val v10 = if (y == 0) zero else (values[Vector2I(x + 1, y)] ?: zero)
+            val v01 = if (x == 0) zero else (values[Vector2I(x, y + 1)] ?: zero)
+            val v11 = (values[Vector2I(x + 1, y + 1)] ?: zero)
+
+            val p00 = Vector2D(x.toDouble(), y.toDouble()) * cellSize + area.topLeft
+            val p10 = Vector2D((x + 1).toDouble(), y.toDouble()) * cellSize + area.topLeft
+            val p01 = Vector2D(x.toDouble(), (y + 1).toDouble()) * cellSize + area.topLeft
+            val p11 = Vector2D((x + 1).toDouble(), (y + 1).toDouble()) * cellSize + area.topLeft
+
+            val index = (if (v00 >= 0.0) 1 else 0) +
+                    (if (v10 >= 0.0) 2 else 0) +
+                    (if (v01 >= 0.0) 4 else 0) +
+                    (if (v11 >= 0.0) 8 else 0)
+
+            fun blend(v1: Double, v2: Double): Double {
+                if (useInterpolation) {
+                    require(!v1.isNaN() && !v2.isNaN()) {
+                        "Input values v1=$v1 or v2=$v2 are NaN, which is not allowed."
+                    }
+                    val f1 = min(v1, v2)
+                    val f2 = max(v1, v2)
+                    val v = (-f1) / (f2 - f1)
+
+                    require(v == v && v in 0.0..1.0) {
+                        "Invalid value calculated during interpolation: v=$v"
+                    }
+
+                    return if (f1 == v1) {
+                        v
+                    } else {
+                        1.0 - v
+                    }
+                } else {
+                    return 0.5
+                }
+            }
+
+            fun emitLine(
+                p00: Vector2D, p01: Vector2D, v00: Double, v01: Double,
+                p10: Vector2D, p11: Vector2D, v10: Double, v11: Double
+            ) {
+                val r0 = blend(v00, v01)
+                val r1 = blend(v10, v11)
+
+                val v0 = p00.mix(p01, r0)
+                val v1 = p10.mix(p11, r1)
+                val l0 = LineSegment(v0, v1)
+                segmentsMap.getOrPut(v1) { mutableListOf() }.add(l0)
+                segmentsMap.getOrPut(v0) { mutableListOf() }.add(l0)
+                segments.add(l0)
+            }
+
+            when (index) {
+                0, 15 -> {}
+                1, 15 xor 1 -> {
+                    emitLine(p00, p01, v00, v01, p00, p10, v00, v10)
+                }
+
+                2, 15 xor 2 -> {
+                    emitLine(p00, p10, v00, v10, p10, p11, v10, v11)
+                }
+
+                3, 15 xor 3 -> {
+                    emitLine(p00, p01, v00, v01, p10, p11, v10, v11)
+                }
+
+                4, 15 xor 4 -> {
+                    emitLine(p00, p01, v00, v01, p01, p11, v01, v11)
+                }
+
+                5, 15 xor 5 -> {
+                    emitLine(p00, p10, v00, v10, p01, p11, v01, v11)
+                }
+
+                6, 15 xor 6 -> {
+                    emitLine(p00, p01, v00, v01, p00, p10, v00, v10)
+                    emitLine(p01, p11, v01, v11, p10, p11, v10, v11)
+                }
+
+                7, 15 xor 7 -> {
+                    emitLine(p01, p11, v01, v11, p10, p11, v10, v11)
+                }
+            }
+        }
+    }
+
+    val processedSegments = mutableSetOf<LineSegment>()
+    val contours = mutableListOf<ShapeContour>()
+    for (segment in segments) {
+        if (segment in processedSegments) {
+            continue
+        } else {
+            val collected = mutableListOf<Vector2D>()
+            var current: LineSegment? = segment
+            var closed = true
+            var lastVertex = Vector2D.INFINITY
+            do {
+                current!!
+                if (lastVertex.squaredDistanceTo(current.start) > 1E-5) {
+                    collected.add(current.start)
+                }
+                lastVertex = current.start
+                processedSegments.add(current)
+                if (segmentsMap[current.start]!!.size < 2) {
+                    closed = false
+                }
+                val hold = current
+                current = segmentsMap[current.start]?.firstOrNull { it !in processedSegments }
+                if (current == null) {
+                    current = segmentsMap[hold.end]?.firstOrNull { it !in processedSegments }
+                }
+            } while (current != segment && current != null)
+
+            contours.add(ShapeContour.fromPoints(collected, closed = closed))
+        }
+    }
+    return contours
+}

android/src/main/res/layout-port/activity_main.xml

@@ -0,0 +1,183 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/main"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical"
+    tools:context=".MainActivity">
+
+    <com.mapbox.maps.MapView
+        android:id="@+id/map_view"
+        android:layout_width="match_parent"
+        android:layout_height="0dp"
+        android:layout_weight="3" />
+
+    <ScrollView
+        android:layout_width="match_parent"
+        android:layout_height="0dp"
+        android:layout_weight="1">
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:orientation="vertical">
+
+            <com.google.android.material.slider.Slider
+                android:id="@+id/slider_target_height"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:value="0"
+                android:valueFrom="0"
+                android:valueTo="100" />
+
+            <LinearLayout
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:gravity="center_vertical"
+                android:orientation="horizontal">
+
+                <TextView
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:text="栅格大小：" />
+
+                <com.google.android.material.slider.Slider
+                    android:id="@+id/cell_size"
+                    android:layout_width="0dp"
+                    android:layout_height="wrap_content"
+                    android:layout_weight="1"
+                    android:value="1"
+                    android:valueFrom="1"
+                    android:valueTo="100" />
+            </LinearLayout>
+
+            <LinearLayout
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:gravity="center_vertical"
+                android:orientation="horizontal">
+
+                <TextView
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:text="高度范围：" />
+
+                <com.google.android.material.slider.RangeSlider
+                    android:id="@+id/height_range"
+                    android:layout_width="0dp"
+                    android:layout_height="wrap_content"
+                    android:layout_weight="1"
+                    android:valueFrom="0"
+                    android:valueTo="100" />
+            </LinearLayout>
+
+            <Switch
+                android:id="@+id/switch_grid"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:switchPadding="16dp"
+                android:text="栅格网" />
+
+            <Switch
+                android:id="@+id/switch_triangle"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:switchPadding="16dp"
+                android:text="三角网" />
+
+            <LinearLayout
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content">
+
+                <TextView
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:text="坐标数量：" />
+
+                <TextView
+                    android:id="@+id/point_count"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content" />
+            </LinearLayout>
+
+            <Button
+                android:id="@+id/update"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="刷新界面" />
+
+            <Button
+                android:id="@+id/clear_points"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="清除所有点" />
+
+            <LinearLayout
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:gravity="center_vertical"
+                android:orientation="horizontal">
+
+                <TextView
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:text="坡向(角度)：" />
+
+                <com.google.android.material.slider.Slider
+                    android:id="@+id/slope_direction"
+                    android:layout_width="0dp"
+                    android:layout_height="wrap_content"
+                    android:layout_weight="1"
+                    android:valueFrom="0"
+                    android:valueTo="360" />
+            </LinearLayout>
+
+            <LinearLayout
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:gravity="center_vertical"
+                android:orientation="horizontal">
+
+                <TextView
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:text="坡度(%)：" />
+
+                <com.google.android.material.slider.Slider
+                    android:id="@+id/slope_percentage"
+                    android:layout_width="0dp"
+                    android:layout_height="wrap_content"
+                    android:layout_weight="1"
+                    android:valueFrom="0"
+                    android:valueTo="100" />
+            </LinearLayout>
+
+            <LinearLayout
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:gravity="center_vertical">
+
+                <TextView
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:text="设计面高度(m)：" />
+
+                <com.google.android.material.slider.Slider
+                    android:id="@+id/design_height"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:value="0"
+                    android:valueFrom="-100"
+                    android:valueTo="100" />
+            </LinearLayout>
+
+            <Switch
+                android:id="@+id/switch_design_surface"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:switchPadding="16dp"
+                android:text="显示设计面" />
+        </LinearLayout>
+    </ScrollView>
+</LinearLayout>

android/src/main/res/layout/activity_main.xml

@@ -1,19 +1,179 @@
 <?xml version="1.0" encoding="utf-8"?>
-<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:app="http://schemas.android.com/apk/res-auto"
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
     android:id="@+id/main"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
+    android:orientation="horizontal"
     tools:context=".MainActivity">
 
+    <LinearLayout
+        android:layout_width="0dp"
+        android:layout_height="match_parent"
+        android:layout_weight="1"
+        android:orientation="vertical"
+        android:paddingTop="32dp">
+
+        <com.google.android.material.slider.Slider
+            android:id="@+id/slider_target_height"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:value="0"
+            android:valueFrom="0"
+            android:valueTo="100" />
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:gravity="center_vertical"
+            android:orientation="horizontal">
+
             <TextView
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
-        android:text="Hello World!"
-        app:layout_constraintBottom_toBottomOf="parent"
-        app:layout_constraintEnd_toEndOf="parent"
-        app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toTopOf="parent" />
+                android:text="栅格大小：" />
 
-</androidx.constraintlayout.widget.ConstraintLayout>
+            <com.google.android.material.slider.Slider
+                android:id="@+id/cell_size"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:value="1"
+                android:valueFrom="1"
+                android:valueTo="100" />
+        </LinearLayout>
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:gravity="center_vertical"
+            android:orientation="horizontal">
+
+            <TextView
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="高度范围：" />
+
+            <com.google.android.material.slider.RangeSlider
+                android:id="@+id/height_range"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:valueFrom="0"
+                android:valueTo="100" />
+        </LinearLayout>
+
+        <Switch
+            android:id="@+id/switch_grid"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:switchPadding="16dp"
+            android:text="栅格网" />
+
+        <Switch
+            android:id="@+id/switch_triangle"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:switchPadding="16dp"
+            android:text="三角网" />
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content">
+
+            <TextView
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="坐标数量：" />
+
+            <TextView
+                android:id="@+id/point_count"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content" />
+        </LinearLayout>
+
+        <Button
+            android:id="@+id/update"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="刷新界面" />
+
+        <Button
+            android:id="@+id/clear_points"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="清除所有点" />
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:gravity="center_vertical"
+            android:orientation="horizontal">
+
+            <TextView
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="坡向(角度)：" />
+
+            <com.google.android.material.slider.Slider
+                android:id="@+id/slope_direction"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:valueFrom="0"
+                android:valueTo="360" />
+        </LinearLayout>
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:gravity="center_vertical"
+            android:orientation="horizontal">
+
+            <TextView
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="坡度(%)：" />
+
+            <com.google.android.material.slider.Slider
+                android:id="@+id/slope_percentage"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:valueFrom="0"
+                android:valueTo="100" />
+        </LinearLayout>
+
+        <LinearLayout
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:gravity="center_vertical">
+
+            <TextView
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="设计面高度(m)：" />
+
+            <com.google.android.material.slider.Slider
+                android:id="@+id/design_height"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:value="0"
+                android:valueFrom="-100"
+                android:valueTo="100" />
+        </LinearLayout>
+
+        <Switch
+            android:id="@+id/switch_design_surface"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:switchPadding="16dp"
+            android:text="显示设计面" />
+    </LinearLayout>
+
+    <com.mapbox.maps.MapView
+        android:id="@+id/map_view"
+        android:layout_width="0dp"
+        android:layout_height="match_parent"
+        android:layout_weight="3" />
+</LinearLayout>

build-logic/orx-convention/src/main/kotlin/org/openrndr/extra/convention/CollectScreenShots.kt

@@ -132,7 +132,7 @@ abstract class CollectScreenshotsTask @Inject constructor() : DefaultTask() {
                     val codeLines = ktFile.readLines()
                     val main = codeLines.indexOfFirst { it.startsWith("fun main") }
                     val head = codeLines.take(main)
-                    val start = head.indexOfLast { it.startsWith("/**") }
+                    val start = head.indexOfLast { it.startsWith("/*") }
                     val end = head.indexOfLast { it.endsWith("*/") }
 
                     if ((start < end) && (end < main)) {

desktop/build.gradle.kts

@@ -30,6 +30,7 @@ kotlin {
                 implementation(project(":orx-marching-squares"))
                 implementation(project(":orx-text-writer"))
                 implementation(project(":orx-obj-loader"))
+                implementation(project(":orx-palette"))
             }
         }
     }

desktop/src/jvmDemo/kotlin/DemoColorBrewer2.kt

@@ -0,0 +1,35 @@
+import org.openrndr.application
+import org.openrndr.shape.Rectangle
+
+/**
+ * Demonstrates how to use a ColorBrewer2 palette.
+ * Finds the first available palette with 5 colors,
+ * then draws concentric circles filled with those colors.
+ */
+fun main() = application {
+    configure {
+        width = 720
+        height = 720
+    }
+    program {
+        val palette = colorBrewer2Palettes(
+            numberOfColors = 6,
+            paletteType = ColorBrewer2Type.Any
+        ).first().colors
+        val cellSize = 50.0
+        extend {
+            palette.forEachIndexed { i, color ->
+                drawer.fill = color
+                drawer.rectangle(
+                    Rectangle(
+                        x = 0.0,
+                        y = cellSize * i,
+                        width = cellSize,
+                        height = cellSize
+                    )
+                )
+                // drawer.circle(drawer.bounds.center, 300.0 - i * 40.0)
+            }
+        }
+    }
+}

desktop/src/jvmDemo/kotlin/DemoDelaunay03.kt

@@ -10,7 +10,6 @@ import org.openrndr.draw.loadFont
 import org.openrndr.extra.camera.Camera2D
 import org.openrndr.extra.marchingsquares.findContours
 import org.openrndr.extra.noise.gradientPerturbFractal
-import org.openrndr.extra.noise.simplex
 import org.openrndr.extra.textwriter.writer
 import org.openrndr.extra.triangulation.DelaunayTriangulation
 import org.openrndr.math.Vector2
@@ -18,7 +17,6 @@ import org.openrndr.math.Vector3
 import org.openrndr.shape.Segment2D
 import org.openrndr.shape.Segment3D
 import org.openrndr.shape.ShapeContour
-import kotlin.math.absoluteValue
 import kotlin.math.cos
 import kotlin.math.sin
 import kotlin.random.Random
@@ -30,7 +28,7 @@ import kotlin.random.Random
 fun main() = application {
     configure {
         width = 720
-        height = 720
+        height = 480
         title = "Delaunator"
     }
     program {
@@ -62,6 +60,10 @@ fun main() = application {
         extend(Camera2D())
         println("draw")
         var targetHeight: Double = zs.average()
+        val step = zs.max() - zs.min() / 6
+        var heightList = (0..5).map { index ->
+            zs.min() + step * index
+        }
         var logEnabled = true
         var useInterpolation = false
         var sampleLinear = false
@@ -171,12 +173,41 @@ fun main() = application {
                 cellSize = 4.0,
                 useInterpolation = useInterpolation
             )
+            val associateWith: List<List<ShapeContour>> = heightList.map { height ->
+                findContours(
+                    f = {
+                        val triangle = triangles.firstOrNull { triangle ->
+                            isPointInTriangle(it, listOf(triangle.x1, triangle.x2, triangle.x3))
+                        }
+                        triangle ?: return@findContours 0.0
+                        val interpolate = interpolateHeight(
+                            point = it,
+                            triangle = listOf(
+                                triangle.x1,
+                                triangle.x2,
+                                triangle.x3,
+                            ).map {
+                                Vector3(it.x, it.y, associate[it]!!)
+                            }
+                        )
+                        interpolate.z - height
+                    },
+                    area = drawer.bounds,
+                    cellSize = 4.0,
+                    useInterpolation = useInterpolation
+                )
+            }
             if (logEnabled) println("useInterpolation = $useInterpolation")
             drawer.stroke = null
-            contours.forEach {
+            if (true) contours.forEach {
                 drawer.fill = ColorRGBa.GREEN.opacify(0.1)
                 drawer.contour(if (sampleLinear) it.sampleLinear() else it)
-
+            }
+            if (false) associateWith.forEachIndexed { index, contours ->
+                contours.forEach {
+                    drawer.fill = colorBrewer2[index].colors.first().opacify(0.1)
+                    drawer.contour(it)
+                }
             }
 
             drawer.fontMap = loadFont("demo-data/fonts/IBMPlexMono-Regular.ttf", 24.0)
@@ -210,6 +241,24 @@ fun isPointInTriangle(point: Vector2, triangle: List<Vector2>): Boolean {
             alpha <= 1 && beta <= 1 && gamma <= 1
 }
 
+fun isPointInTriangle3D(point: Vector2, triangle: List<Vector3>): Boolean {
+    require(triangle.size == 3) { "三角形必须有3个顶点" }
+
+    val (v1, v2, v3) = triangle
+
+    // 计算重心坐标
+    val denominator = (v2.y - v3.y) * (v1.x - v3.x) + (v3.x - v2.x) * (v1.y - v3.y)
+    if (denominator == 0.0) return false // 退化三角形
+
+    val alpha = ((v2.y - v3.y) * (point.x - v3.x) + (v3.x - v2.x) * (point.y - v3.y)) / denominator
+    val beta = ((v3.y - v1.y) * (point.x - v3.x) + (v1.x - v3.x) * (point.y - v3.y)) / denominator
+    val gamma = 1.0 - alpha - beta
+
+    // 点在三角形内当且仅当所有重心坐标都在[0,1]范围内
+    return alpha >= 0 && beta >= 0 && gamma >= 0 &&
+            alpha <= 1 && beta <= 1 && gamma <= 1
+}
+
 /**
  * 使用重心坐标计算点在三角形上的高度
  * @param point 二维点 (x, y)

desktop/src/jvmDemo/kotlin/DemoDelaunay3D.kt

@@ -9,15 +9,14 @@ import org.openrndr.draw.loadFont
 import org.openrndr.draw.shadeStyle
 import org.openrndr.extra.camera.Orbital
 import org.openrndr.extra.marchingsquares.findContours
-import org.openrndr.extra.noise.gradientPerturbFractal
 import org.openrndr.extra.objloader.loadOBJasVertexBuffer
 import org.openrndr.extra.textwriter.writer
 import org.openrndr.extra.triangulation.DelaunayTriangulation
+import org.openrndr.extra.triangulation.DelaunayTriangulation3D
 import org.openrndr.math.Vector2
 import org.openrndr.math.Vector3
 import org.openrndr.shape.Path3D
 import org.openrndr.shape.Segment3D
-import org.openrndr.shape.ShapeContour
 
 /**
  * @author tabidachinokaze
@@ -49,7 +48,7 @@ fun main() = application {
             volcanoCount = 3
         )*/
         val points3D = coordinateGenerate(width, height).map {
-             it.copy(x = it.x - width / 2, y = it.y - height / 2)
+            it.copy(x = it.x - width / 2, y = it.y - height / 2, z = it.z * 10)
         }
         val zs = points3D.map { it.z }
         println("zs = ${zs}")
@@ -57,6 +56,7 @@ fun main() = application {
             Vector2(it.x, it.y) to it.z
         }.toMutableMap()
         val delaunay = DelaunayTriangulation(associate.map { it.key })
+        val delaunay3D = DelaunayTriangulation3D(points3D.map { Vector3(it.x, it.y, it.z) })
 
         //println(points3D.niceStr())
         //extend(Camera2D())
@@ -84,7 +84,7 @@ fun main() = application {
         val vb = loadOBJasVertexBuffer("orx-obj-loader/test-data/non-planar.obj")
 
         extend {
-            val triangles = delaunay.triangles()
+            val triangles = delaunay3D.triangles()
             val segments = mutableListOf<Segment3D>()
             drawer.clear(ColorRGBa.BLACK)
             val indexDiff = (frameCount / 1000) % triangles.size
@@ -95,10 +95,12 @@ fun main() = application {
             }
 
             drawer.vertexBuffer(vb, DrawPrimitive.TRIANGLES)
+
+            // 绘制等高线段区域
             for ((i, triangle) in triangles.withIndex()) {
-                val segment2DS = triangle.contour.segments.filter {
-                    val startZ = associate[it.start]!!
-                    val endZ = associate[it.end]!!
+                val segment2DS = triangle.segments.filter {
+                    val startZ = it.start.z
+                    val endZ = it.end.z
                     if (startZ < endZ) {
                         targetHeight in startZ..endZ
                     } else {
@@ -108,8 +110,8 @@ fun main() = application {
 
                 if (segment2DS.size == 2) {
                     val vector2s = segment2DS.map {
-                        val startZ = associate[it.start]!!
-                        val endZ = associate[it.end]!!
+                        val startZ = it.start.z
+                        val endZ = it.end.z
                         val start = Vector3(it.start.x, it.start.y, startZ)
                         val end = Vector3(it.end.x, it.end.y, endZ)
                         if (startZ < endZ) {
@@ -130,14 +132,8 @@ fun main() = application {
                 }
                 drawer.strokeWeight = 20.0
                 drawer.stroke = ColorRGBa.PINK
-                val segment3DS = triangle.contour.segments.map {
-                    val startZ = associate[it.start]!!
-                    val endZ = associate[it.end]!!
-                    Segment3D(it.start.vector3(z = startZ), it.end.vector3(z = endZ))
-                }
-
                 //drawer.contour(triangle.contour)
-                drawer.path(Path3D.fromSegments(segment3DS, closed = true))
+                drawer.path(triangle.path)
             }
 
             val sorted = connectAllSegments(segments)
@@ -161,6 +157,7 @@ fun main() = application {
                 drawer.fill = ColorRGBa.YELLOW
                 // if (false) drawer.contour(ShapeContour.fromSegments(it, closed = true))
             }
+            // 结束绘制等高线
             /*for (y in 0 until (area.height / cellSize).toInt()) {
                 for (x in 0 until (area.width / cellSize).toInt()) {
                     values[IntVector2(x, y)] = f(Vector2(x * cellSize + area.x, y * cellSize + area.y))
@@ -169,7 +166,7 @@ fun main() = application {
             val contours = findContours(
                 f = {
                     val triangle = triangles.firstOrNull { triangle ->
-                        isPointInTriangle(it, listOf(triangle.x1, triangle.x2, triangle.x3))
+                        isPointInTriangle3D(it, listOf(triangle.x1, triangle.x2, triangle.x3))
                     }
                     triangle ?: return@findContours 0.0
                     val interpolate = interpolateHeight(
@@ -178,9 +175,7 @@ fun main() = application {
                             triangle.x1,
                             triangle.x2,
                             triangle.x3,
-                        ).map {
-                            Vector3(it.x, it.y, associate[it]!!)
-                        }
+                        )
                     )
                     interpolate.z - targetHeight
                 },
@@ -191,6 +186,7 @@ fun main() = application {
             if (logEnabled) println("useInterpolation = $useInterpolation")
             drawer.stroke = null
             contours.map {
+                if (false) drawer.contour(it)
                 it.segments.map {
                     Segment3D(
                         it.start.vector3(),

icegps-triangulation/.gitignore

@@ -0,0 +1 @@
+/build

icegps-triangulation/build.gradle.kts

@@ -0,0 +1,16 @@
+plugins {
+    id("java-library")
+    alias(libs.plugins.kotlin.jvm)
+}
+java {
+    sourceCompatibility = JavaVersion.VERSION_17
+    targetCompatibility = JavaVersion.VERSION_17
+}
+kotlin {
+    compilerOptions {
+        jvmTarget = org.jetbrains.kotlin.gradle.dsl.JvmTarget.JVM_17
+    }
+}
+dependencies {
+    implementation(project(":math"))
+}

icegps-triangulation/src/main/java/com/icegps/triangulation/Delaunator.kt

@@ -0,0 +1,596 @@
+package com.icegps.triangulation
+
+import kotlin.math.*
+
+val EPSILON: Double = 2.0.pow(-52)
+
+/**
+ * A Kotlin port of Mapbox's Delaunator incredibly fast JavaScript library for Delaunay triangulation of 2D points.
+ *
+ * @description Port of Mapbox's Delaunator (JavaScript) library - https://github.com/mapbox/delaunator
+ * @property coords flat positions' array - [x0, y0, x1, y1..]
+ *
+ * @since f0ed80d - commit
+ * @author Ricardo Matias
+ */
+@Suppress("unused")
+class Delaunator(val coords: DoubleArray) {
+    val EDGE_STACK = IntArray(512)
+
+    private var count = coords.size shr 1
+
+    // arrays that will store the triangulation graph
+    val maxTriangles = (2 * count - 5).coerceAtLeast(0)
+    private val _triangles = IntArray(maxTriangles * 3)
+    private val _halfedges = IntArray(maxTriangles * 3)
+
+    lateinit var triangles: IntArray
+    lateinit var halfedges: IntArray
+
+    // temporary arrays for tracking the edges of the advancing convex hull
+    private var hashSize = ceil(sqrt(count * 1.0)).toInt()
+    private var hullPrev = IntArray(count) // edge to prev edge
+    private var hullNext = IntArray(count) // edge to next edge
+    private var hullTri = IntArray(count) // edge to adjacent triangle
+    private var hullHash = IntArray(hashSize) // angular edge hash
+    private var hullStart: Int = -1
+
+    // temporary arrays for sorting points
+    private var ids = IntArray(count)
+    private var dists = DoubleArray(count)
+
+    private var cx: Double = Double.NaN
+    private var cy: Double = Double.NaN
+
+    private var trianglesLen: Int = -1
+
+    lateinit var hull: IntArray
+
+    init {
+        update()
+    }
+
+    fun update() {
+        if (coords.size <= 2) {
+            halfedges = IntArray(0)
+            triangles = IntArray(0)
+            hull = IntArray(0)
+            return
+        }
+
+
+        // populate an array of point indices calculate input data bbox
+        var minX = Double.POSITIVE_INFINITY
+        var minY = Double.POSITIVE_INFINITY
+        var maxX = Double.NEGATIVE_INFINITY
+        var maxY = Double.NEGATIVE_INFINITY
+
+        // points -> points
+        // minX, minY, maxX, maxY
+        for (i in 0 until count) {
+            val x = coords[2 * i]
+            val y = coords[2 * i + 1]
+            if (x < minX) minX = x
+            if (y < minY) minY = y
+            if (x > maxX) maxX = x
+            if (y > maxY) maxY = y
+
+            ids[i] = i
+        }
+
+        val cx = (minX + maxX) / 2
+        val cy = (minY + maxY) / 2
+
+        var minDist = Double.POSITIVE_INFINITY
+
+        var i0: Int = -1
+        var i1: Int = -1
+        var i2: Int = -1
+
+        // pick a seed point close to the center
+        for (i in 0 until count) {
+            val d = dist(cx, cy, coords[2 * i], coords[2 * i + 1])
+
+            if (d < minDist) {
+                i0 = i
+                minDist = d
+            }
+        }
+
+        val i0x = coords[2 * i0]
+        val i0y = coords[2 * i0 + 1]
+
+        minDist = Double.POSITIVE_INFINITY
+
+        // Find the point closest to the seed
+        for(i in 0 until count) {
+            if (i == i0) continue
+
+            val d = dist(i0x, i0y, coords[2 * i], coords[2 * i + 1])
+
+            if (d < minDist && d > 0) {
+                i1 = i
+                minDist = d
+            }
+        }
+
+        var i1x = coords[2 * i1]
+        var i1y = coords[2 * i1 + 1]
+
+        var minRadius = Double.POSITIVE_INFINITY
+
+        // Find the third point which forms the smallest circumcircle with the first two
+        for (i in 0 until count) {
+            if(i == i0 || i == i1) continue
+
+            val r = circumradius(i0x, i0y, i1x, i1y, coords[2 * i], coords[2 * i + 1])
+
+            if(r < minRadius) {
+                i2 = i
+                minRadius = r
+            }
+        }
+
+        if (minRadius == Double.POSITIVE_INFINITY) {
+            // order collinear points by dx (or dy if all x are identical)
+            // and return the list as a hull
+            for (i in 0 until count) {
+                val a = (coords[2 * i] - coords[0])
+                val b = (coords[2 * i + 1] - coords[1])
+                dists[i] =  if (a == 0.0) b else a
+            }
+
+            quicksort(ids, dists, 0, count - 1)
+
+            val nhull = IntArray(count)
+            var j = 0
+            var d0 = Double.NEGATIVE_INFINITY
+
+            for (i in 0 until count) {
+                val id = ids[i]
+                if (dists[id] > d0) {
+                    nhull[j++] = id
+                    d0 = dists[id]
+                }
+            }
+
+            hull = nhull.copyOf(j)
+            triangles = IntArray(0)
+            halfedges = IntArray(0)
+
+            return
+        }
+
+        var i2x = coords[2 * i2]
+        var i2y = coords[2 * i2 + 1]
+
+        // swap the order of the seed points for counter-clockwise orientation
+        if (orient2d(i0x, i0y, i1x, i1y, i2x, i2y) < 0.0) {
+            val i = i1
+            val x = i1x
+            val y = i1y
+            i1 = i2
+            i1x = i2x
+            i1y = i2y
+            i2 = i
+            i2x = x
+            i2y = y
+        }
+
+
+        val center = circumcenter(i0x, i0y, i1x, i1y, i2x, i2y)
+
+        this.cx = center[0]
+        this.cy = center[1]
+
+        for (i in 0 until count) {
+            dists[i] = dist(coords[2 * i], coords[2 * i + 1], center[0], center[1])
+        }
+
+        // sort the points by distance from the seed triangle circumcenter
+        quicksort(ids, dists, 0, count - 1)
+
+        // set up the seed triangle as the starting hull
+        hullStart = i0
+        var hullSize = 3
+
+        hullNext[i0] = i1
+        hullNext[i1] = i2
+        hullNext[i2] = i0
+
+        hullPrev[i2] = i1
+        hullPrev[i0] = i2
+        hullPrev[i1] = i0
+
+        hullTri[i0] = 0
+        hullTri[i1] = 1
+        hullTri[i2] = 2
+
+        hullHash.fill(-1)
+        hullHash[hashKey(i0x, i0y)] = i0
+        hullHash[hashKey(i1x, i1y)] = i1
+        hullHash[hashKey(i2x, i2y)] = i2
+
+        trianglesLen = 0
+        addTriangle(i0, i1, i2, -1, -1, -1)
+
+        var xp = 0.0
+        var yp = 0.0
+
+        for (k in ids.indices) {
+            val i = ids[k]
+            val x = coords[2 * i]
+            val y = coords[2 * i + 1]
+
+            // skip near-duplicate points
+            if (k > 0 && abs(x - xp) <= EPSILON && abs(y - yp) <= EPSILON) continue
+
+            xp = x
+            yp = y
+
+            // skip seed triangle points
+            if (i == i0 || i == i1 || i == i2) continue
+
+            // find a visible edge on the convex hull using edge hash
+            var start = 0
+            val key = hashKey(x, y)
+
+            for (j in 0 until hashSize) {
+                start = hullHash[(key + j) % hashSize]
+
+                if (start != -1 && start != hullNext[start]) break
+            }
+
+            start = hullPrev[start]
+
+            var e = start
+            var q = hullNext[e]
+
+            while (orient2d(x, y, coords[2 * e], coords[2 * e + 1], coords[2 * q], coords[2 * q + 1]) >= 0) {
+                e = q
+
+                if (e == start) {
+                    e = -1
+                    break
+                }
+
+                q = hullNext[e]
+            }
+
+            if (e == -1) continue // likely a near-duplicate point skip it
+
+            // add the first triangle from the point
+            var t = addTriangle(e, i, hullNext[e], -1, -1, hullTri[e])
+
+            // recursively flip triangles from the point until they satisfy the Delaunay condition
+            hullTri[i] = legalize(t + 2)
+            hullTri[e] = t // keep track of boundary triangles on the hull
+            hullSize++
+
+            // walk forward through the hull, adding more triangles and flipping recursively
+            var next = hullNext[e]
+            q = hullNext[next]
+
+            while (orient2d(x, y, coords[2 * next], coords[2 * next + 1], coords[2 * q], coords[2 * q + 1]) < 0) {
+                t = addTriangle(next, i, q, hullTri[i], -1, hullTri[next])
+                hullTri[i] = legalize(t + 2)
+                hullNext[next] = next // mark as removed
+                hullSize--
+
+                next = q
+                q = hullNext[next]
+            }
+
+            // walk backward from the other side, adding more triangles and flipping
+            if (e == start) {
+                q = hullPrev[e]
+
+                while (orient2d(x, y, coords[2 * q], coords[2 * q + 1], coords[2 * e], coords[2 * e + 1]) < 0) {
+                    t = addTriangle(q, i, e, -1, hullTri[e], hullTri[q])
+                    legalize(t + 2)
+                    hullTri[q] = t
+                    hullNext[e] = e // mark as removed
+                    hullSize--
+
+                    e = q
+                    q = hullPrev[e]
+                }
+            }
+
+            // update the hull indices
+            hullStart = e
+            hullPrev[i] = e
+
+            hullNext[e] = i
+            hullPrev[next] = i
+            hullNext[i] = next
+
+            // save the two new edges in the hash table
+            hullHash[hashKey(x, y)] = i
+            hullHash[hashKey(coords[2 * e], coords[2 * e + 1])] = e
+        }
+
+        hull = IntArray(hullSize)
+
+        var e = hullStart
+
+        for (i in 0 until hullSize) {
+            hull[i] = e
+            e = hullNext[e]
+        }
+
+        // trim typed triangle mesh arrays
+        triangles = _triangles.copyOf(trianglesLen)
+        halfedges = _halfedges.copyOf(trianglesLen)
+    }
+
+    private fun legalize(a: Int): Int {
+        var i = 0
+        var na = a
+        var ar: Int
+
+        // recursion eliminated with a fixed-size stack
+        while (true) {
+            val b = _halfedges[na]
+
+            /* if the pair of triangles doesn't satisfy the Delaunay condition
+             * (p1 is inside the circumcircle of [p0, pl, pr]), flip them,
+             * then do the same check/flip recursively for the new pair of triangles
+             *
+             *           pl                    pl
+             *          /||\                  /  \
+             *       al/ || \bl            al/    \a
+             *        /  ||  \              /      \
+             *       /  a||b  \    flip    /___ar___\
+             *     p0\   ||   /p1   =>   p0\---bl---/p1
+             *        \  ||  /              \      /
+             *       ar\ || /br             b\    /br
+             *          \||/                  \  /
+             *           pr                    pr
+             */
+            val a0 = na - na % 3
+            ar = a0 + (na + 2) % 3
+
+            if (b == -1) { // convex hull edge
+                if (i == 0) break
+                na = EDGE_STACK[--i]
+                continue
+            }
+
+            val b0 = b - b % 3
+            val al = a0 + (na + 1) % 3
+            val bl = b0 + (b + 2) % 3
+
+            val p0 = _triangles[ar]
+            val pr = _triangles[na]
+            val pl = _triangles[al]
+            val p1 = _triangles[bl]
+
+            val illegal = inCircleRobust(
+                coords[2 * p0], coords[2 * p0 + 1],
+                coords[2 * pr], coords[2 * pr + 1],
+                coords[2 * pl], coords[2 * pl + 1],
+                coords[2 * p1], coords[2 * p1 + 1])
+
+            if (illegal) {
+                _triangles[na] = p1
+                _triangles[b] = p0
+
+                val hbl = _halfedges[bl]
+
+                // edge swapped on the other side of the hull (rare) fix the halfedge reference
+                if (hbl == -1) {
+                    var e = hullStart
+                    do {
+                        if (hullTri[e] == bl) {
+                            hullTri[e] = na
+                            break
+                        }
+                        e = hullPrev[e]
+                    } while (e != hullStart)
+                }
+                link(na, hbl)
+                link(b, _halfedges[ar])
+                link(ar, bl)
+
+                val br = b0 + (b + 1) % 3
+
+                // don't worry about hitting the cap: it can only happen on extremely degenerate input
+                if (i < EDGE_STACK.size) {
+                    EDGE_STACK[i++] = br
+                }
+            } else {
+                if (i == 0) break
+                na = EDGE_STACK[--i]
+            }
+        }
+
+        return ar
+
+    }
+
+    private fun link(a:Int, b:Int) {
+        _halfedges[a] = b
+        if (b != -1) _halfedges[b] = a
+    }
+
+    // add a new triangle given vertex indices and adjacent half-edge ids
+    private fun addTriangle(i0: Int, i1: Int, i2: Int, a: Int, b: Int, c: Int): Int {
+        val t = trianglesLen
+
+        _triangles[t] = i0
+        _triangles[t + 1] = i1
+        _triangles[t + 2] = i2
+
+        link(t, a)
+        link(t + 1, b)
+        link(t + 2, c)
+
+        trianglesLen += 3
+
+        return t
+    }
+
+    private fun hashKey(x: Double, y: Double): Int {
+        return (floor(pseudoAngle(x - cx, y - cy) * hashSize) % hashSize).toInt()
+    }
+}
+
+fun circumradius(ax: Double, ay: Double,
+                 bx: Double, by: Double,
+                 cx: Double, cy: Double): Double {
+    val dx = bx - ax
+    val dy = by - ay
+    val ex = cx - ax
+    val ey = cy - ay
+
+    val bl = dx * dx + dy * dy
+    val cl = ex * ex + ey * ey
+    val d = 0.5 / (dx * ey - dy * ex)
+
+    val x = (ey * bl - dy * cl) * d
+    val y = (dx * cl - ex * bl) * d
+
+    return x * x + y * y
+}
+
+fun circumcenter(ax: Double, ay: Double,
+                 bx: Double, by: Double,
+                 cx: Double, cy: Double): DoubleArray {
+    val dx = bx - ax
+    val dy = by - ay
+    val ex = cx - ax
+    val ey = cy - ay
+
+    val bl = dx * dx + dy * dy
+    val cl = ex * ex + ey * ey
+    val d = 0.5 / (dx * ey - dy * ex)
+
+    val x = ax + (ey * bl - dy * cl) * d
+    val y = ay + (dx * cl - ex * bl) * d
+
+    return doubleArrayOf(x, y)
+}
+
+fun quicksort(ids: IntArray, dists: DoubleArray, left: Int, right: Int) {
+    if (right - left <= 20) {
+        for (i in (left + 1)..right) {
+            val temp = ids[i]
+            val tempDist = dists[temp]
+            var j = i - 1
+            while (j >= left && dists[ids[j]] > tempDist) ids[j + 1] = ids[j--]
+            ids[j + 1] = temp
+        }
+    } else {
+        val median = (left + right) shr 1
+        var i = left + 1
+        var j = right
+
+        swap(ids, median, i)
+
+        if (dists[ids[left]] > dists[ids[right]]) swap(ids, left, right)
+        if (dists[ids[i]] > dists[ids[right]]) swap(ids, i, right)
+        if (dists[ids[left]] > dists[ids[i]]) swap(ids, left, i)
+
+        val temp = ids[i]
+        val tempDist = dists[temp]
+
+        while (true) {
+            do i++ while (dists[ids[i]] < tempDist)
+            do j-- while (dists[ids[j]] > tempDist)
+            if (j < i) break
+            swap(ids, i, j)
+        }
+
+        ids[left + 1] = ids[j]
+        ids[j] = temp
+
+        if (right - i + 1 >= j - left) {
+            quicksort(ids, dists, i, right)
+            quicksort(ids, dists, left, j - 1)
+        } else {
+            quicksort(ids, dists, left, j - 1)
+            quicksort(ids, dists, i, right)
+        }
+    }
+}
+
+private fun swap(arr: IntArray, i: Int, j: Int) {
+    val tmp = arr[i]
+    arr[i] = arr[j]
+    arr[j] = tmp
+}
+
+// monotonically increases with real angle, but doesn't need expensive trigonometry
+private fun pseudoAngle(dx: Double, dy: Double): Double {
+    val p = dx / (abs(dx) + abs(dy))
+    val a =  if (dy > 0.0) 3.0 - p else 1.0 + p
+
+    return a / 4.0 // [0..1]
+}
+
+private fun inCircle(ax: Double, ay: Double,
+                     bx: Double, by: Double,
+                     cx: Double, cy: Double,
+                     px: Double, py: Double): Boolean {
+    val dx = ax - px
+    val dy = ay - py
+    val ex = bx - px
+    val ey = by - py
+    val fx = cx - px
+    val fy = cy - py
+
+    val ap = dx * dx + dy * dy
+    val bp = ex * ex + ey * ey
+    val cp = fx * fx + fy * fy
+
+    return dx * (ey * cp - bp * fy) -
+            dy * (ex * cp - bp * fx) +
+            ap * (ex * fy - ey * fx) < 0
+}
+
+private fun inCircleRobust(
+    ax: Double, ay: Double,
+    bx: Double, by: Double,
+    cx: Double, cy: Double,
+    px: Double, py: Double
+): Boolean {
+
+    val dx = twoDiff(ax, px)
+    val dy = twoDiff(ay, py)
+    val ex = twoDiff(bx, px)
+    val ey = twoDiff(by, py)
+    val fx = twoDiff(cx, px)
+    val fy = twoDiff(cy, py)
+
+    val ap = ddAddDd(ddMultDd(dx, dx), ddMultDd(dy, dy))
+    val bp = ddAddDd(ddMultDd(ex, ex), ddMultDd(ey, ey))
+    val cp = ddAddDd(ddMultDd(fx, fx), ddMultDd(fy, fy))
+
+    val dd = ddAddDd(
+        ddDiffDd(
+            ddMultDd(dx, ddDiffDd(ddMultDd(ey, cp), ddMultDd(bp, fy))),
+            ddMultDd(dy, ddDiffDd(ddMultDd(ex, cp), ddMultDd(bp, fx)))
+        ),
+        ddMultDd(ap, ddDiffDd(ddMultDd(ex, fy), ddMultDd(ey, fx)))
+    )
+    return (dd[1]) <= 0
+}
+
+
+private fun dist(ax: Double, ay: Double, bx: Double, by: Double): Double {
+    //val dx = ax - bx
+    //val dy = ay - by
+    //return dx * dx + dy * dy
+
+    // double-double implementation but I think it is overkill.
+
+    val dx = twoDiff(ax, bx)
+    val dy = twoDiff(ay, by)
+    val dx2 = ddMultDd(dx, dx)
+    val dy2 = ddMultDd(dy, dy)
+    val d2 = ddAddDd(dx2, dy2)
+
+    return d2[0] + d2[1]
+
+}

icegps-triangulation/src/main/java/com/icegps/triangulation/Delaunay.kt

@@ -0,0 +1,225 @@
+package com.icegps.triangulation
+
+import com.icegps.math.geometry.Vector2D
+import com.icegps.triangulation.Delaunay.Companion.from
+import kotlin.math.cos
+import kotlin.math.pow
+import kotlin.math.sin
+
+/*
+ISC License
+
+Copyright 2021 Ricardo Matias.
+
+Permission to use, copy, modify, and/or distribute this software for any purpose
+with or without fee is hereby granted, provided that the above copyright notice
+and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
+THIS SOFTWARE.
+*/
+
+/**
+ * Use [from] static method to use the delaunay triangulation
+ *
+ * @description Port of d3-delaunay (JavaScript) library - https://github.com/d3/d3-delaunay
+ * @property points flat positions' array - [x0, y0, x1, y1..]
+ *
+ * @since 9258fa3 - commit
+ * @author Ricardo Matias
+ */
+@Suppress("unused")
+class Delaunay(val points: DoubleArray) {
+    companion object {
+        /**
+         * Entry point for the delaunay triangulation
+         *
+         * @property points a list of 2D points
+         */
+        fun from(points: List<Vector2D>): Delaunay {
+            val n = points.size
+            val coords = DoubleArray(n * 2)
+
+            for (i in points.indices) {
+                val p = points[i]
+                coords[2 * i] = p.x
+                coords[2 * i + 1] = p.y
+            }
+
+            return Delaunay(coords)
+        }
+    }
+
+    private var delaunator: Delaunator = Delaunator(points)
+
+    val inedges = IntArray(points.size / 2)
+    private val hullIndex = IntArray(points.size / 2)
+
+    var halfedges: IntArray = delaunator.halfedges
+    var hull: IntArray = delaunator.hull
+    var triangles: IntArray = delaunator.triangles
+
+    init {
+        init()
+    }
+
+    fun update() {
+        delaunator.update()
+        init()
+    }
+
+    fun neighbors(i: Int) = sequence<Int> {
+        val e0 = inedges[i]
+        if (e0 != -1) {
+            var e = e0
+            var p0 = -1
+
+            loop@ do {
+                p0 = triangles[e]
+                yield(p0)
+                e = if (e % 3 == 2) e - 2 else e + 1
+                if (e == -1) {
+                    break@loop
+                }
+
+                if (triangles[e] != i) {
+                    break@loop
+                    //error("bad triangulation")
+                }
+                e = halfedges[e]
+
+                if (e == -1) {
+                    val p = hull[(hullIndex[i] + 1) % hull.size]
+                    if (p != p0) {
+                        yield(p)
+                    }
+                    break@loop
+                }
+            } while (e != e0)
+        }
+    }
+
+    fun collinear(): Boolean {
+        for (i in 0 until triangles.size step 3) {
+            val a = 2 * triangles[i]
+            val b = 2 * triangles[i + 1]
+            val c = 2 * triangles[i + 2]
+            val coords = points
+            val cross = (coords[c] - coords[a]) * (coords[b + 1] - coords[a + 1])
+            -(coords[b] - coords[a]) * (coords[c + 1] - coords[a + 1])
+            if (cross > 1e-10) return false;
+        }
+        return true
+    }
+
+    private fun jitter(x: Double, y: Double, r: Double): DoubleArray {
+        return doubleArrayOf(x + sin(x + y) * r, y + cos(x - y) * r)
+    }
+
+    fun init() {
+
+        if (hull.size > 2 && collinear()) {
+            println("warning: triangulation is collinear")
+            val r = 1E-8
+            for (i in 0 until points.size step 2) {
+                val p = jitter(points[i], points[i + 1], r)
+                points[i] = p[0]
+                points[i + 1] = p[1]
+            }
+
+            delaunator = Delaunator(points)
+            halfedges = delaunator.halfedges
+            hull = delaunator.hull
+            triangles = delaunator.triangles
+
+        }
+
+
+
+        inedges.fill(-1)
+        hullIndex.fill(-1)
+
+        // Compute an index from each point to an (arbitrary) incoming halfedge
+        // Used to give the first neighbor of each point for this reason,
+        // on the hull we give priority to exterior halfedges
+        for (e in halfedges.indices) {
+            val p = triangles[nextHalfedge(e)]
+
+            if (halfedges[e] == -1 || inedges[p] == -1) inedges[p] = e
+        }
+
+        for (i in hull.indices) {
+            hullIndex[hull[i]] = i
+        }
+
+        // degenerate case: 1 or 2 (distinct) points
+        if (hull.size in 1..2) {
+            triangles = IntArray(3) { -1 }
+            halfedges = IntArray(3) { -1 }
+            triangles[0] = hull[0]
+            inedges[hull[0]] = 1
+            if (hull.size == 2) {
+                inedges[hull[1]] = 0
+                triangles[1] = hull[1]
+                triangles[2] = hull[1]
+            }
+        }
+    }
+
+
+    fun find(x: Double, y: Double, i: Int = 0): Int {
+        var i1 = i
+        var c = step(i, x, y)
+
+        while (c >= 0 && c != i && c != i1) {
+            i1 = c
+            c = step(i1, x, y)
+        }
+        return c
+    }
+
+    fun nextHalfedge(e: Int) = if (e % 3 == 2) e - 2 else e + 1
+    fun prevHalfedge(e: Int) = if (e % 3 == 0) e + 2 else e - 1
+
+    fun step(i: Int, x: Double, y: Double): Int {
+        if (inedges[i] == -1 || points.isEmpty()) return (i + 1) % (points.size shr 1)
+
+        var c = i
+        var dc = (x - points[i * 2]).pow(2) + (y - points[i * 2 + 1]).pow(2)
+        val e0 = inedges[i]
+        var e = e0
+        do {
+            val t = triangles[e]
+            val dt = (x - points[t * 2]).pow(2) + (y - points[t * 2 + 1]).pow(2)
+
+            if (dt < dc) {
+                dc = dt
+                c = t
+            }
+
+            e = if (e % 3 == 2) e - 2 else e + 1
+
+            if (triangles[e] != i) {
+                //error("bad triangulation")
+                break
+            } // bad triangulation
+
+            e = halfedges[e]
+
+            if (e == -1) {
+                e = hull[(hullIndex[i] + 1) % hull.size]
+                if (e != t) {
+                    if ((x - points[e * 2]).pow(2) + (y - points[e * 2 + 1]).pow(2) < dc) return e
+                }
+                break
+            }
+        } while (e != e0)
+
+        return c
+    }
+}

icegps-triangulation/src/main/java/com/icegps/triangulation/DelaunayTriangulation.kt

@@ -0,0 +1,69 @@
+package com.icegps.triangulation
+
+import com.icegps.math.geometry.Vector3D
+import com.icegps.math.geometry.toVector2D
+
+/**
+ * Kotlin/OPENRNDR idiomatic interface to `Delaunay`
+ */
+class DelaunayTriangulation(val points: List<Vector3D>) {
+    val delaunay: Delaunay = Delaunay.from(points.map { it.toVector2D() })
+
+    fun neighbors(pointIndex: Int): Sequence<Int> {
+        return delaunay.neighbors(pointIndex)
+    }
+
+    fun neighborPoints(pointIndex: Int): List<Vector3D> {
+        return neighbors(pointIndex).map { points[it] }.toList()
+    }
+
+    fun triangleIndices(): List<IntArray> {
+        val list = mutableListOf<IntArray>()
+        for (i in delaunay.triangles.indices step 3) {
+            list.add(
+                intArrayOf(
+                    delaunay.triangles[i],
+                    delaunay.triangles[i + 1],
+                    delaunay.triangles[i + 2]
+                )
+            )
+        }
+        return list
+    }
+
+    fun triangles(filterPredicate: (Int, Int, Int) -> Boolean = { _, _, _ -> true }): List<Triangle> {
+        val list = mutableListOf<Triangle>()
+
+        for (i in delaunay.triangles.indices step 3) {
+            val t0 = delaunay.triangles[i]
+            val t1 = delaunay.triangles[i + 1]
+            val t2 = delaunay.triangles[i + 2]
+
+            // originally they are defined *counterclockwise*
+            if (filterPredicate(t2, t1, t0)) {
+                val p1 = points[t0]
+                val p2 = points[t1]
+                val p3 = points[t2]
+                list.add(Triangle(p3, p2, p1))
+            }
+        }
+        return list
+    }
+
+    fun nearest(query: Vector3D): Int = delaunay.find(query.x, query.y)
+
+    fun nearestPoint(query: Vector3D): Vector3D = points[nearest(query)]
+}
+
+/**
+ * Computes the Delaunay triangulation for the list of 2D points.
+ *
+ * The Delaunay triangulation is a triangulation of a set of points such that
+ * no point is inside the circumcircle of any triangle. It maximizes the minimum
+ * angle of all the angles in the triangles, avoiding skinny triangles.
+ *
+ * @return A DelaunayTriangulation object representing the triangulation of the given points.
+ */
+fun List<Vector3D>.delaunayTriangulation(): DelaunayTriangulation {
+    return DelaunayTriangulation(this)
+}

icegps-triangulation/src/main/java/com/icegps/triangulation/DoubleDouble.kt

@@ -0,0 +1,340 @@
+package com.icegps.triangulation
+
+import kotlin.math.pow
+
+// original code: https://github.com/FlorisSteenkamp/double-double/
+
+
+/**
+ * Returns the difference and exact error of subtracting two floating point
+ * numbers.
+ * Uses an EFT (error-free transformation), i.e. `a-b === x+y` exactly.
+ * The returned result is a non-overlapping expansion (smallest value first!).
+ *
+ * * **precondition:** `abs(a) >= abs(b)` - A fast test that can be used is
+ * `(a > b) === (a > -b)`
+ *
+ * See https://people.eecs.berkeley.edu/~jrs/papers/robustr.pdf
+ */
+fun fastTwoDiff(a: Double, b: Double): DoubleArray {
+    val x = a - b;
+    val y = (a - x) - b;
+
+    return doubleArrayOf(y, x)
+}
+
+/**
+ * Returns the sum and exact error of adding two floating point numbers.
+ * Uses an EFT (error-free transformation), i.e. a+b === x+y exactly.
+ * The returned sum is a non-overlapping expansion (smallest value first!).
+ *
+ * Precondition: abs(a) >= abs(b) - A fast test that can be used is
+ * (a > b) === (a > -b)
+ *
+ * See https://people.eecs.berkeley.edu/~jrs/papers/robustr.pdf
+ */
+fun fastTwoSum(a: Double, b: Double): DoubleArray {
+    val x = a + b;
+
+    return doubleArrayOf(b - (x - a), x)
+}
+
+
+/**
+ * Truncates a floating point value's significand and returns the result.
+ * Similar to split, but with the ability to specify the number of bits to keep.
+ *
+ * **Theorem 17 (Veltkamp-Dekker)**: Let a be a p-bit floating-point number, where
+ * p >= 3. Choose a splitting point s such that p/2 <= s <= p-1. Then the
+ * following algorithm will produce a (p-s)-bit value a_hi and a
+ * nonoverlapping (s-1)-bit value a_lo such that abs(a_hi) >= abs(a_lo) and
+ * a = a_hi + a_lo.
+ *
+ * * see [Shewchuk](https://people.eecs.berkeley.edu/~jrs/papers/robustr.pdf)
+ *
+ * @param a a double
+ * @param bits the number of significand bits to leave intact
+ */
+fun reduceSignificand(
+    a: Double,
+    bits: Int
+): Double {
+
+    val s = 53 - bits;
+    val f = 2.0.pow(s) + 1;
+
+    val c = f * a;
+    val r = c - (c - a);
+
+    return r;
+}
+
+
+/**
+ * === 2^Math.ceil(p/2) + 1 where p is the # of significand bits in a double === 53.
+ * @internal
+ */
+const val f = 134217729;  // 2**27 + 1;
+
+
+/**
+ * Returns the result of splitting a double into 2 26-bit doubles.
+ *
+ * Theorem 17 (Veltkamp-Dekker): Let a be a p-bit floating-point number, where
+ * p >= 3. Choose a splitting point s such that p/2 <= s <= p-1. Then the
+ * following algorithm will produce a (p-s)-bit value a_hi and a
+ * nonoverlapping (s-1)-bit value a_lo such that abs(a_hi) >= abs(a_lo) and
+ * a = a_hi + a_lo.
+ *
+ * see e.g. [Shewchuk](https://people.eecs.berkeley.edu/~jrs/papers/robustr.pdf)
+ * @param a A double floating point number
+ */
+fun split(a: Double): DoubleArray {
+    val c = f * a;
+    val a_h = c - (c - a);
+    val a_l = a - a_h;
+
+    return doubleArrayOf(a_h, a_l)
+}
+
+/**
+ * Returns the exact result of subtracting b from a.
+ *
+ * @param a minuend - a double-double precision floating point number
+ * @param b subtrahend - a double-double precision floating point number
+ */
+fun twoDiff(a: Double, b: Double): DoubleArray {
+    val x = a - b;
+    val bvirt = a - x;
+    val y = (a - (x + bvirt)) + (bvirt - b);
+
+    return doubleArrayOf(y, x)
+}
+
+/**
+ * Returns the exact result of multiplying two doubles.
+ *
+ * * the resulting array is the reverse of the standard twoSum in the literature.
+ *
+ * Theorem 18 (Shewchuk): Let a and b be p-bit floating-point numbers, where
+ * p >= 6. Then the following algorithm will produce a nonoverlapping expansion
+ * x + y such that ab = x + y, where x is an approximation to ab and y
+ * represents the roundoff error in the calculation of x. Furthermore, if
+ * round-to-even tiebreaking is used, x and y are non-adjacent.
+ *
+ * See https://people.eecs.berkeley.edu/~jrs/papers/robustr.pdf
+ * @param a A double
+ * @param b Another double
+ */
+fun twoProduct(a: Double, b: Double): DoubleArray {
+    val x = a * b;
+
+    //const [ah, al] = split(a);
+    val c = f * a;
+    val ah = c - (c - a);
+    val al = a - ah;
+    //const [bh, bl] = split(b);
+    val d = f * b;
+    val bh = d - (d - b);
+    val bl = b - bh;
+
+    val y = (al * bl) - ((x - (ah * bh)) - (al * bh) - (ah * bl));
+
+    //const err1 = x - (ah * bh);
+    //const err2 = err1 - (al * bh);
+    //const err3 = err2 - (ah * bl);
+    //const y = (al * bl) - err3;
+
+    return doubleArrayOf(y, x)
+}
+
+fun twoSquare(a: Double): DoubleArray {
+    val x = a * a;
+
+    //const [ah, al] = split(a);
+    val c = f * a;
+    val ah = c - (c - a);
+    val al = a - ah;
+
+    val y = (al * al) - ((x - (ah * ah)) - 2 * (ah * al));
+
+    return doubleArrayOf(y, x)
+}
+
+/**
+ * Returns the exact result of adding two doubles.
+ *
+ * * the resulting array is the reverse of the standard twoSum in the literature.
+ *
+ * Theorem 7 (Knuth): Let a and b be p-bit floating-point numbers. Then the
+ * following algorithm will produce a nonoverlapping expansion x + y such that
+ * a + b = x + y, where x is an approximation to a + b and y is the roundoff
+ * error in the calculation of x.
+ *
+ * See https://people.eecs.berkeley.edu/~jrs/papers/robustr.pdf
+ */
+fun twoSum(a: Double, b: Double): DoubleArray {
+    val x = a + b;
+    val bv = x - a;
+
+    return doubleArrayOf((a - (x - bv)) + (b - bv), x)
+}
+
+/**
+ * Returns the result of subtracting the second given double-double-precision
+ * floating point number from the first.
+ *
+ * * relative error bound: 3u^2 + 13u^3, i.e. fl(a-b) = (a-b)(1+ϵ),
+ * where ϵ <= 3u^2 + 13u^3, u = 0.5 * Number.EPSILON
+ * * the error bound is not sharp - the worst case that could be found by the
+ * authors were 2.25u^2
+ *
+ * ALGORITHM 6 of https://hal.archives-ouvertes.fr/hal-01351529v3/document
+ * @param x a double-double precision floating point number
+ * @param y another double-double precision floating point number
+ */
+fun ddDiffDd(x: DoubleArray, y: DoubleArray): DoubleArray {
+    val xl = x[0];
+    val xh = x[1];
+    val yl = y[0];
+    val yh = y[1];
+
+    //const [sl,sh] = twoSum(xh,yh);
+    val sh = xh - yh;
+    val _1 = sh - xh;
+    val sl = (xh - (sh - _1)) + (-yh - _1);
+    //const [tl,th] = twoSum(xl,yl);
+    val th = xl - yl;
+    val _2 = th - xl;
+    val tl = (xl - (th - _2)) + (-yl - _2);
+    val c = sl + th;
+    //const [vl,vh] = fastTwoSum(sh,c)
+    val vh = sh + c;
+    val vl = c - (vh - sh);
+    val w = tl + vl
+    //const [zl,zh] = fastTwoSum(vh,w)
+    val zh = vh + w;
+    val zl = w - (zh - vh);
+
+    return doubleArrayOf(zl, zh)
+}
+
+/**
+ * Returns the product of two double-double-precision floating point numbers.
+ *
+ * * relative error bound: 7u^2, i.e. fl(a+b) = (a+b)(1+ϵ),
+ * where ϵ <= 7u^2, u = 0.5 * Number.EPSILON
+ * the error bound is not sharp - the worst case that could be found by the
+ * authors were 5u^2
+ *
+ * * ALGORITHM 10 of https://hal.archives-ouvertes.fr/hal-01351529v3/document
+ * @param x a double-double precision floating point number
+ * @param y another double-double precision floating point number
+ */
+fun ddMultDd(x: DoubleArray, y: DoubleArray): DoubleArray {
+
+
+    //const xl = x[0];
+    val xh = x[1];
+    //const yl = y[0];
+    val yh = y[1];
+
+    //const [cl1,ch] = twoProduct(xh,yh);
+    val ch = xh * yh;
+    val c = f * xh;
+    val ah = c - (c - xh);
+    val al = xh - ah;
+    val d = f * yh;
+    val bh = d - (d - yh);
+    val bl = yh - bh;
+    val cl1 = (al * bl) - ((ch - (ah * bh)) - (al * bh) - (ah * bl));
+
+    //return fastTwoSum(ch,cl1 + (xh*yl + xl*yh));
+    val b = cl1 + (xh * y[0] + x[0] * yh);
+    val xx = ch + b;
+
+    return doubleArrayOf(b - (xx - ch), xx)
+}
+
+
+/**
+ * Returns the result of adding two double-double-precision floating point
+ * numbers.
+ *
+ * * relative error bound: 3u^2 + 13u^3, i.e. fl(a+b) = (a+b)(1+ϵ),
+ * where ϵ <= 3u^2 + 13u^3, u = 0.5 * Number.EPSILON
+ * * the error bound is not sharp - the worst case that could be found by the
+ * authors were 2.25u^2
+ *
+ * ALGORITHM 6 of https://hal.archives-ouvertes.fr/hal-01351529v3/document
+ * @param x a double-double precision floating point number
+ * @param y another double-double precision floating point number
+ */
+fun ddAddDd(x: DoubleArray, y: DoubleArray): DoubleArray {
+    val xl = x[0];
+    val xh = x[1];
+    val yl = y[0];
+    val yh = y[1];
+
+    //const [sl,sh] = twoSum(xh,yh);
+    val sh = xh + yh;
+    val _1 = sh - xh;
+    val sl = (xh - (sh - _1)) + (yh - _1);
+    //val [tl,th] = twoSum(xl,yl);
+    val th = xl + yl;
+    val _2 = th - xl;
+    val tl = (xl - (th - _2)) + (yl - _2);
+    val c = sl + th;
+    //val [vl,vh] = fastTwoSum(sh,c)
+    val vh = sh + c;
+    val vl = c - (vh - sh);
+    val w = tl + vl
+    //val [zl,zh] = fastTwoSum(vh,w)
+    val zh = vh + w;
+    val zl = w - (zh - vh);
+
+    return doubleArrayOf(zl, zh)
+}
+
+
+/**
+ * Returns the product of a double-double-precision floating point number and a
+ * double.
+ *
+ * * slower than ALGORITHM 8 (one call to fastTwoSum more) but about 2x more
+ * accurate
+ * * relative error bound: 1.5u^2 + 4u^3, i.e. fl(a+b) = (a+b)(1+ϵ),
+ * where ϵ <= 1.5u^2 + 4u^3, u = 0.5 * Number.EPSILON
+ * * the bound is very sharp
+ * * probably prefer `ddMultDouble2` due to extra speed
+ *
+ * * ALGORITHM 7 of https://hal.archives-ouvertes.fr/hal-01351529v3/document
+ * @param y a double
+ * @param x a double-double precision floating point number
+ */
+fun ddMultDouble1(y: Double, x: DoubleArray): DoubleArray {
+    val xl = x[0];
+    val xh = x[1];
+
+    //val [cl1,ch] = twoProduct(xh,y);
+    val ch = xh * y;
+    val c = f * xh;
+    val ah = c - (c - xh);
+    val al = xh - ah;
+    val d = f * y;
+    val bh = d - (d - y);
+    val bl = y - bh;
+    val cl1 = (al * bl) - ((ch - (ah * bh)) - (al * bh) - (ah * bl));
+
+    val cl2 = xl * y;
+    //val [tl1,th] = fastTwoSum(ch,cl2);
+    val th = ch + cl2;
+    val tl1 = cl2 - (th - ch);
+
+    val tl2 = tl1 + cl1;
+    //val [zl,zh] = fastTwoSum(th,tl2);
+    val zh = th + tl2;
+    val zl = tl2 - (zh - th);
+
+    return doubleArrayOf(zl, zh);
+}

icegps-triangulation/src/main/java/com/icegps/triangulation/Predicates.kt

@@ -0,0 +1,19 @@
+package com.icegps.triangulation
+
+fun orient2d(bx: Double, by: Double, ax: Double, ay: Double, cx: Double, cy: Double): Double {
+    // (ax,ay) (bx,by) are swapped such that the sign of the determinant is flipped. which is what Delaunator.kt expects.
+
+    /*
+    | a  b | = | ax - cx  ay - cy |
+    | c  d |   | bx - cx  by - cy |
+    */
+
+    val a = twoDiff(ax, cx)
+    val b = twoDiff(ay, cy)
+    val c = twoDiff(bx, cx)
+    val d = twoDiff(by, cy)
+
+    val determinant = ddDiffDd(ddMultDd(a, d), ddMultDd(b, c))
+
+    return determinant[1]
+}

icegps-triangulation/src/main/java/com/icegps/triangulation/Triangle.kt

@@ -0,0 +1,13 @@
+package com.icegps.triangulation
+
+import com.icegps.math.geometry.Vector3D
+
+/**
+ * @author tabidachinokaze
+ * @date 2025/11/26
+ */
+data class Triangle(
+    val x1: Vector3D,
+    val x2: Vector3D,
+    val x3: Vector3D,
+)

math/src/main/java/com/icegps/math/geometry/VectorsDouble.kt

@@ -121,6 +121,13 @@ data class Vector2D(val x: Double, val y: Double) : IsAlmostEquals<Vector2D> {
     fun distanceTo(x: Int, y: Int): Double = this.distanceTo(x.toDouble(), y.toDouble())
     fun distanceTo(that: Vector2D): Double = distanceTo(that.x, that.y)
 
+    /** Calculates the squared Euclidean distance to [other]. */
+    fun squaredDistanceTo(other: Vector2D): Double {
+        val dx = other.x - x
+        val dy = other.y - y
+        return dx * dx + dy * dy
+    }
+
     infix fun cross(that: Vector2D): Double = crossProduct(this, that)
     infix fun dot(that: Vector2D): Double = ((this.x * that.x) + (this.y * that.y))
 
@@ -195,6 +202,8 @@ data class Vector2D(val x: Double, val y: Double) : IsAlmostEquals<Vector2D> {
         /** DOWN using screen coordinates as reference (0, +1) */
         val DOWN_SCREEN = Vector2D(0.0, +1.0)
 
+        val INFINITY = Vector2D(Double.POSITIVE_INFINITY, Double.POSITIVE_INFINITY)
+
 
         inline operator fun invoke(x: Number, y: Number): Vector2D = Vector2D(x.toDouble(), y.toDouble())
         //inline operator fun invoke(x: Float, y: Float): Vector2D = Vector2D(x.toDouble(), y.toDouble())

orx-color/README.md

@@ -51,7 +51,12 @@ Two color spaces are added: `ColorHSLUVa` and `ColorHPLUVa`, they are an impleme
 ## Demos
 ### colormap/DemoSpectralZucconiColormap
 
+This program demonstrates the `spectralZucconi6()` function, which
+takes a normalized value and returns a `ColorRGBa` using the
+accurate spectral colormap developed by Alan Zucconi.
 
+It draws a varying number of vertical bands (between 16 and 48)
+filled with various hues.
 
 ![colormap-DemoSpectralZucconiColormapKt](https://raw.githubusercontent.com/openrndr/orx/media/orx-color/images/colormap-DemoSpectralZucconiColormapKt.png)
 
@@ -59,7 +64,13 @@ Two color spaces are added: `ColorHSLUVa` and `ColorHPLUVa`, they are an impleme
 
 ### colormap/DemoSpectralZucconiColormapPhrase
 
+This program demonstrates how to use the shader-based version of
+the `spectral_zucconi6()` function, which
+takes a normalized value and returns an `rgb` color using the
+accurate spectral colormap developed by Alan Zucconi.
 
+It shades a full-window rectangle using its normalized `x` coordinate
+in a `ShadeStyle` to choose pixel colors.
 
 ![colormap-DemoSpectralZucconiColormapPhraseKt](https://raw.githubusercontent.com/openrndr/orx/media/orx-color/images/colormap-DemoSpectralZucconiColormapPhraseKt.png)
 
@@ -67,7 +78,11 @@ Two color spaces are added: `ColorHSLUVa` and `ColorHPLUVa`, they are an impleme
 
 ### colormap/DemoSpectralZucconiColormapPlot
 
+This demo uses the shader based `spectral_zucconi6()` function to fill the background,
+then visualizes the red, green and blue components of the colors used in the background
+as red, green and blue line strips.
 
+The Vector2 points for the line strips are calculated only once when the program starts.
 
 ![colormap-DemoSpectralZucconiColormapPlotKt](https://raw.githubusercontent.com/openrndr/orx/media/orx-color/images/colormap-DemoSpectralZucconiColormapPlotKt.png)
 
@@ -75,7 +90,12 @@ Two color spaces are added: `ColorHSLUVa` and `ColorHPLUVa`, they are an impleme
 
 ### colormap/DemoTurboColormap
 
+This program demonstrates the `turboColormap()` function, which
+takes a normalized value and returns a `ColorRGBa` using the
+Turbo colormap developed by Google.
 
+It draws a varying number of vertical bands (between 16 and 48)
+filled with various hues.
 
 ![colormap-DemoTurboColormapKt](https://raw.githubusercontent.com/openrndr/orx/media/orx-color/images/colormap-DemoTurboColormapKt.png)
 
@@ -83,7 +103,13 @@ Two color spaces are added: `ColorHSLUVa` and `ColorHPLUVa`, they are an impleme
 
 ### colormap/DemoTurboColormapPhrase
 
+This program demonstrates how to use the shader-based version of
+the `turbo_colormap()` function, which
+takes a normalized value and returns an `rgb` color using the
+Turbo colormap developed by Google.
 
+It shades a full-window rectangle using its normalized `x` coordinate
+in a `ShadeStyle` to choose pixel colors.
 
 ![colormap-DemoTurboColormapPhraseKt](https://raw.githubusercontent.com/openrndr/orx/media/orx-color/images/colormap-DemoTurboColormapPhraseKt.png)
 
@@ -91,7 +117,11 @@ Two color spaces are added: `ColorHSLUVa` and `ColorHPLUVa`, they are an impleme
 
 ### colormap/DemoTurboColormapPlot
 
+This demo uses the shader based `turbo_colormap()` function to fill the background,
+then visualizes the red, green and blue components of the colors used in the background
+as red, green and blue line strips.
 
+The Vector2 points for the line strips are calculated only once when the program starts.
 
 ![colormap-DemoTurboColormapPlotKt](https://raw.githubusercontent.com/openrndr/orx/media/orx-color/images/colormap-DemoTurboColormapPlotKt.png)
 
@@ -171,7 +201,8 @@ to position the images dynamically based on their index within the grid.
 
 ### colorRange/DemoColorRange01
 
-
+Comparison of color lists generated by interpolating from
+`PINK` to `BLUE` in six different color spaces.
 
 ![colorRange-DemoColorRange01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-color/images/colorRange-DemoColorRange01Kt.png)
 
@@ -179,7 +210,13 @@ to position the images dynamically based on their index within the grid.
 
 ### colorRange/DemoColorRange02
 
+Demonstrates how to create a `ColorSequence` containing three colors, one of them in the HSLUV color space.
 
+Each color in the sequence is assigned a normalized position: in this program, one at the start (0.0),
+one in the middle (0.5) and one at the end (1.0).
+
+The `ColorSpace.blend()` method is used to get a list with 18 interpolated `ColorRGBa` colors,
+then those colors are drawn as vertical rectangles covering the whole window.
 
 ![colorRange-DemoColorRange02Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-color/images/colorRange-DemoColorRange02Kt.png)
 
@@ -187,7 +224,13 @@ to position the images dynamically based on their index within the grid.
 
 ### colorRange/DemoColorRange03
 
+This program creates color interpolations from `ColorRGBa.BLUE` to
+`ColorRGBa.PINK` in 25 steps in multiple color spaces.
 
+The window height is adjusted based on the number of interpolations to show.
+
+The resulting gradients differ in saturation and brightness and apparently include more
+`BLUE` or more `PINK` depending on the chosen color space.
 
 ![colorRange-DemoColorRange03Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-color/images/colorRange-DemoColorRange03Kt.png)
 
@@ -195,6 +238,17 @@ to position the images dynamically based on their index within the grid.
 
 ### colorRange/DemoColorRange04
 
+A visualization of color interpolations inside a 3D RGB cube with an interactive 3D `Orbital` camera.
+
+The hues of the source and target colors are animated over time.
+
+The color interpolations are shown simultaneously in nine different color spaces, revealing how in
+each case they share common starting and ending points in 3D, but have unique paths going from
+start to end.
+
+By rotating the cube 90 degrees towards the left and slightly zooming out, one can appreciate how
+one of the points moves along the edges of the cube, while the other moves on the edges of a
+smaller, invisible cube.
 
 
 ![colorRange-DemoColorRange04Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-color/images/colorRange-DemoColorRange04Kt.png)
@@ -337,13 +391,6 @@ The rendering process includes:
 
 ### histogram/DemoHistogram01
 
-package histogram
-
-import org.openrndr.application
-import org.openrndr.draw.loadImage
-import org.openrndr.extra.color.statistics.calculateHistogramRGB
-
-/*
 Demonstrates how to generate a palette with the top 32 colors
 of a loaded image, sorted by luminosity. The colors are displayed
 as rectangles overlayed on top of the image.
@@ -354,14 +401,6 @@ as rectangles overlayed on top of the image.
 
 ### histogram/DemoHistogram02
 
-package histogram
-
-import org.openrndr.application
-import org.openrndr.draw.loadImage
-import org.openrndr.extra.color.statistics.calculateHistogramRGB
-import kotlin.math.pow
-
-/*
 Show the color histogram of an image using non-uniform weighting,
 prioritizing bright colors.
 
@@ -371,13 +410,6 @@ prioritizing bright colors.
 
 ### histogram/DemoHistogram03
 
-package histogram
-
-import org.openrndr.application
-import org.openrndr.draw.loadImage
-import org.openrndr.extra.color.statistics.calculateHistogramRGB
-
-/*
 Create a simple grid-like composition based on colors sampled from image.
 The cells are 32 by 32 pixels in size and are filled with a random sample
 taken from the color histogram of the image.

orx-color/src/jvmDemo/kotlin/colorRange/DemoColorRange01.kt

@@ -1,8 +1,5 @@
 package colorRange
 
-// Comparison of color lists generated by interpolating from
-// PINK to BLUE in different color models
-
 import org.openrndr.application
 import org.openrndr.color.ColorRGBa
 import org.openrndr.extra.color.palettes.rangeTo
@@ -11,6 +8,10 @@ import org.openrndr.math.Vector2
 import org.openrndr.math.map
 import org.openrndr.shape.Rectangle
 
+/**
+ * Comparison of color lists generated by interpolating from
+ * `PINK` to `BLUE` in six different color spaces.
+ */
 fun main() = application {
     configure {
         width = 720

orx-color/src/jvmDemo/kotlin/colorRange/DemoColorRange02.kt

@@ -1,12 +1,19 @@
 package colorRange
 
-// Create a colorSequence with multiple color models
-
 import org.openrndr.application
 import org.openrndr.color.ColorRGBa
 import org.openrndr.extra.color.palettes.colorSequence
 import org.openrndr.extra.color.spaces.toHSLUVa
 
+/**
+ * Demonstrates how to create a `ColorSequence` containing three colors, one of them in the HSLUV color space.
+ *
+ * Each color in the sequence is assigned a normalized position: in this program, one at the start (0.0),
+ * one in the middle (0.5) and one at the end (1.0).
+ *
+ * The `ColorSpace.blend()` method is used to get a list with 18 interpolated `ColorRGBa` colors,
+ * then those colors are drawn as vertical rectangles covering the whole window.
+ */
 fun main() = application {
     configure {
         width = 720
@@ -14,9 +21,11 @@ fun main() = application {
     }
     program {
         extend {
-            val cs = colorSequence(0.0 to ColorRGBa.PINK,
+            val cs = colorSequence(
+                0.0 to ColorRGBa.PINK,
                 0.5 to ColorRGBa.BLUE,
-                    1.0 to ColorRGBa.PINK.toHSLUVa()) // <-- note this one is in hsluv
+                1.0 to ColorRGBa.PINK.toHSLUVa() // <-- note this color is in HSLUV
+            )
 
             for (c in cs blend (width / 40)) {
                 drawer.fill = c

orx-color/src/jvmDemo/kotlin/colorRange/DemoColorRange03.kt

@@ -6,15 +6,16 @@ import org.openrndr.draw.loadFont
 import org.openrndr.extra.color.palettes.rangeTo
 import org.openrndr.extra.color.spaces.*
 
+/**
+ * This program creates color interpolations from `ColorRGBa.BLUE` to
+ * `ColorRGBa.PINK` in 25 steps in multiple color spaces.
+ *
+ * The window height is adjusted based on the number of interpolations to show.
+ *
+ * The resulting gradients differ in saturation and brightness and apparently include more
+ * `BLUE` or more `PINK` depending on the chosen color space.
+ */
 fun main() = application {
-    configure {
-        width = 720
-        height = 30 + 50 * 11 // row count
-    }
-    program {
-        extend {
-            drawer.clear(ColorRGBa.WHITE)
-
     val colorA = ColorRGBa.BLUE
     val colorB = ColorRGBa.PINK
 
@@ -34,8 +35,14 @@ fun main() = application {
         "XSLUV" to (colorA.toXSLUVa()..colorB.toXSLUVa() blend stepCount),
     )
 
+    configure {
+        width = 720
+        height = 30 + 50 * allSteps.size
+    }
+    program {
+        extend {
+            drawer.clear(ColorRGBa.WHITE)
             drawer.stroke = null
-
             drawer.fontMap = loadFont("demo-data/fonts/IBMPlexMono-Regular.ttf", 16.0)
             drawer.translate(20.0, 20.0)
             for ((label, steps) in allSteps) {

orx-color/src/jvmDemo/kotlin/colorRange/DemoColorRange04.kt

@@ -14,6 +14,20 @@ import org.openrndr.extra.color.spaces.toXSLUVa
 import org.openrndr.extra.meshgenerators.sphereMesh
 import org.openrndr.math.Vector3
 
+/**
+ * A visualization of color interpolations inside a 3D RGB cube with an interactive 3D `Orbital` camera.
+ *
+ * The hues of the source and target colors are animated over time.
+ *
+ * The color interpolations are shown simultaneously in nine different color spaces, revealing how in
+ * each case they share common starting and ending points in 3D, but have unique paths going from
+ * start to end.
+ *
+ * By rotating the cube 90 degrees towards the left and slightly zooming out, one can appreciate how
+ * one of the points moves along the edges of the cube, while the other moves on the edges of a
+ * smaller, invisible cube.
+ *
+ */
 fun main() = application {
     configure {
         width = 720
@@ -44,9 +58,6 @@ fun main() = application {
                 "XSLUV" to (colorA.toXSLUVa()..colorB.toXSLUVa() blend stepCount),
             )
 
-            drawer.stroke = null
-
-            drawer.fontMap = loadFont("demo-data/fonts/IBMPlexMono-Regular.ttf", 16.0)
             for ((_, steps) in allSteps) {
                 for (i in steps.indices) {
                     val srgb = steps[i].toSRGB().clip()

orx-color/src/jvmDemo/kotlin/colormap/DemoSpectralZucconiColormap.kt

@@ -5,6 +5,14 @@ import org.openrndr.extra.color.colormaps.spectralZucconi6
 import org.openrndr.extra.noise.fastFloor
 import kotlin.math.sin
 
+/**
+ * This program demonstrates the `spectralZucconi6()` function, which
+ * takes a normalized value and returns a `ColorRGBa` using the
+ * accurate spectral colormap developed by Alan Zucconi.
+ *
+ * It draws a varying number of vertical bands (between 16 and 48)
+ * filled with various hues.
+ */
 fun main() = application {
     configure {
         width = 720
@@ -14,12 +22,13 @@ fun main() = application {
         extend {
             drawer.stroke = null
             val stripeCount = 32 + (sin(seconds) * 16.0).fastFloor()
+            val bandWidth = width / stripeCount.toDouble()
             repeat(stripeCount) { i ->
                 drawer.fill = spectralZucconi6(i / stripeCount.toDouble())
                 drawer.rectangle(
-                    x = i * width / stripeCount.toDouble(),
+                    x = i * bandWidth,
                     y = 0.0,
-                    width = width / stripeCount.toDouble(),
+                    width = bandWidth,
                     height = height.toDouble(),
                 )
             }

orx-color/src/jvmDemo/kotlin/colormap/DemoSpectralZucconiColormapPhrase.kt

@@ -5,6 +5,15 @@ import org.openrndr.draw.shadeStyle
 import org.openrndr.extra.color.colormaps.ColormapPhraseBook
 import org.openrndr.extra.shaderphrases.preprocess
 
+/**
+ * This program demonstrates how to use the shader-based version of
+ * the `spectral_zucconi6()` function, which
+ * takes a normalized value and returns an `rgb` color using the
+ * accurate spectral colormap developed by Alan Zucconi.
+ *
+ * It shades a full-window rectangle using its normalized `x` coordinate
+ * in a `ShadeStyle` to choose pixel colors.
+ */
 fun main() = application {
     configure {
         width = 720

orx-color/src/jvmDemo/kotlin/colormap/DemoSpectralZucconiColormapPlot.kt

@@ -8,6 +8,13 @@ import org.openrndr.extra.color.colormaps.spectralZucconi6
 import org.openrndr.extra.shaderphrases.preprocess
 import org.openrndr.math.Vector2
 
+/**
+ * This demo uses the shader based `spectral_zucconi6()` function to fill the background,
+ * then visualizes the red, green and blue components of the colors used in the background
+ * as red, green and blue line strips.
+ *
+ * The Vector2 points for the line strips are calculated only once when the program starts.
+ */
 fun main() = application {
     configure {
         width = 720
@@ -20,14 +27,14 @@ fun main() = application {
             fragmentTransform = "x_fill.rgb = spectral_zucconi6(c_boundsPosition.x);"
         }
 
+        // Function that expects as an argument a function to convert a ColorRGBa into a Double,
+        // and returns a list of Vector2 coordinates.
         fun getColormapPoints(
             block: ColorRGBa.() -> Double
         ) = List(width) { x ->
             Vector2(
                 x.toDouble(),
-                height.toDouble()
-                        - block(spectralZucconi6(x / width.toDouble()))
-                        * height.toDouble()
+                (1.0 - block(spectralZucconi6(x / width.toDouble()))) * height
             )
         }
 
@@ -39,11 +46,13 @@ fun main() = application {
                 shadeStyle = backgroundStyle
                 rectangle(bounds)
                 shadeStyle = null
-                strokeWeight = 1.0
+
                 stroke = ColorRGBa.RED
                 lineStrip(redPoints)
+
                 stroke = ColorRGBa.GREEN
                 lineStrip(greenPoints)
+
                 stroke = ColorRGBa.BLUE
                 lineStrip(bluePoints)
             }

orx-color/src/jvmDemo/kotlin/colormap/DemoTurboColormap.kt

@@ -5,6 +5,15 @@ import org.openrndr.extra.color.colormaps.turboColormap
 import org.openrndr.extra.noise.fastFloor
 import kotlin.math.sin
 
+/**
+ * This program demonstrates the `turboColormap()` function, which
+ * takes a normalized value and returns a `ColorRGBa` using the
+ * Turbo colormap developed by Google.
+ *
+ * It draws a varying number of vertical bands (between 16 and 48)
+ * filled with various hues.
+ */
+
 fun main() = application {
     configure {
         width = 720

orx-color/src/jvmDemo/kotlin/colormap/DemoTurboColormapPhrase.kt

@@ -5,6 +5,15 @@ import org.openrndr.draw.shadeStyle
 import org.openrndr.extra.color.colormaps.ColormapPhraseBook
 import org.openrndr.extra.shaderphrases.preprocess
 
+/**
+ * This program demonstrates how to use the shader-based version of
+ * the `turbo_colormap()` function, which
+ * takes a normalized value and returns an `rgb` color using the
+ * Turbo colormap developed by Google.
+ *
+ * It shades a full-window rectangle using its normalized `x` coordinate
+ * in a `ShadeStyle` to choose pixel colors.
+ */
 fun main() = application {
     configure {
         width = 720

orx-color/src/jvmDemo/kotlin/colormap/DemoTurboColormapPlot.kt

@@ -8,6 +8,13 @@ import org.openrndr.extra.color.colormaps.turboColormap
 import org.openrndr.extra.shaderphrases.preprocess
 import org.openrndr.math.Vector2
 
+/**
+ * This demo uses the shader based `turbo_colormap()` function to fill the background,
+ * then visualizes the red, green and blue components of the colors used in the background
+ * as red, green and blue line strips.
+ *
+ * The Vector2 points for the line strips are calculated only once when the program starts.
+ */
 fun main() = application {
     configure {
         width = 720
@@ -23,10 +30,8 @@ fun main() = application {
             block: ColorRGBa.() -> Double
         ) = List(width) { x ->
             Vector2(
-                x = x.toDouble(),
-                y = height.toDouble()
-                    - block(turboColormap(x / width.toDouble()))
-                    * height.toDouble()
+                x.toDouble(),
+                (1.0 - block(turboColormap(x / width.toDouble()))) * height
             )
         }
         val redPoints = getColormapPoints { r }
@@ -37,11 +42,13 @@ fun main() = application {
                 shadeStyle = backgroundStyle
                 rectangle(bounds)
                 shadeStyle = null
-                strokeWeight = 1.0
+
                 stroke = ColorRGBa.RED
                 lineStrip(redPoints)
+
                 stroke = ColorRGBa.GREEN
                 lineStrip(greenPoints)
+
                 stroke = ColorRGBa.BLUE
                 lineStrip(bluePoints)
             }

orx-jvm/orx-boofcv/README.md

@@ -26,7 +26,16 @@ this addon provides some helper functions to convert them to OPENRNDR types:
 ## Demos
 ### DemoContours01
 
+Demonstrates how to convert a PNG image into `ShapeContour`s using BoofCV.
 
+Two helper methods help convert data types between BoofCV and OPENRNDR.
+
+The `ColorBuffer.toGrayF32()` method converts an OPENRNDR `ColorBuffer` to `GrayF32` format,
+required by BoofCV.
+
+The `.toShapeContours()` converts BoofCV contours to OPENRNDR `ShapeContour` instances.
+
+The resulting contours are animated zooming in and out while their colors change slowly.
 
 ![DemoContours01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-boofcv/images/DemoContours01Kt.png)
 
@@ -34,7 +43,8 @@ this addon provides some helper functions to convert them to OPENRNDR types:
 
 ### DemoResize01
 
-
+Demonstrates how to scale down images using the `resizeBy` BoofCV-based
+method.
 
 ![DemoResize01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-boofcv/images/DemoResize01Kt.png)
 
@@ -42,7 +52,11 @@ this addon provides some helper functions to convert them to OPENRNDR types:
 
 ### DemoResize02
 
+Demonstrates how to scale down images using the `resizeTo` BoofCV-based
+method.
 
+If only the `newWidth` or the `newHeight` arguments are specified,
+the resizing happens maintaining the original aspect ratio.
 
 ![DemoResize02Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-boofcv/images/DemoResize02Kt.png)
 
@@ -50,7 +64,16 @@ this addon provides some helper functions to convert them to OPENRNDR types:
 
 ### DemoSimplified01
 
+When converting a `ColorBuffer` to `ShapeContour` instances using
+`BoofCV`, simple shapes can have hundreds of segments and vertices.
 
+This demo shows how to use the `simplify()` method to greatly
+reduce the number of vertices.
+
+Then it uses the simplified vertex lists to create smooth curves
+(using `CatmullRomChain2`) and polygonal curves (using `ShapeContour.fromPoints`).
+
+Study the console to learn about the number of segments before and after simplification.
 
 ![DemoSimplified01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-boofcv/images/DemoSimplified01Kt.png)
 

orx-jvm/orx-boofcv/src/demo/kotlin/DemoContours01.kt

@@ -12,6 +12,18 @@ import org.openrndr.draw.loadImage
 import kotlin.math.cos
 import kotlin.math.sin
 
+/**
+ * Demonstrates how to convert a PNG image into `ShapeContour`s using BoofCV.
+ *
+ * Two helper methods help convert data types between BoofCV and OPENRNDR.
+ *
+ * The `ColorBuffer.toGrayF32()` method converts an OPENRNDR `ColorBuffer` to `GrayF32` format,
+ * required by BoofCV.
+ *
+ * The `.toShapeContours()` converts BoofCV contours to OPENRNDR `ShapeContour` instances.
+ *
+ * The resulting contours are animated zooming in and out while their colors change slowly.
+ */
 fun main() = application {
     program {
         // Load an image, convert to BoofCV format using orx-boofcv

orx-jvm/orx-boofcv/src/demo/kotlin/DemoResize01.kt

@@ -2,19 +2,31 @@ import org.openrndr.application
 import org.openrndr.boofcv.binding.resizeBy
 import org.openrndr.color.ColorRGBa
 import org.openrndr.draw.loadImage
+import org.openrndr.math.Vector2
 
+/**
+ * Demonstrates how to scale down images using the `resizeBy` BoofCV-based
+ * method.
+ */
 fun main() = application {
     program {
-        // Load an image, convert to BoofCV format using orx-boofcv
         val input = loadImage("demo-data/images/image-001.png")
 
         val scaled = input.resizeBy(0.5)
         val scaled2 = input.resizeBy(0.25, convertToGray = true)
         val scaled3 = input.resizeBy(0.1)
 
+        println("${input.width} x ${input.height}")
+        println("${scaled.width} x ${scaled.height}")
+
         extend {
             drawer.clear(ColorRGBa.BLACK)
             drawer.translate(0.0, (height - scaled.bounds.height) / 2.0)
+
+            // Display the loaded image to the right of `scaled` matching its size
+            drawer.image(input, scaled.bounds.movedBy(Vector2.UNIT_X * scaled.bounds.width))
+
+            // Display actually scaled down versions of the loaded image
             drawer.image(scaled)
             drawer.image(scaled2, scaled.bounds.width, scaled.bounds.height - scaled2.height)
             drawer.image(scaled3, scaled.bounds.width + scaled2.bounds.width, scaled.bounds.height - scaled3.height)

orx-jvm/orx-boofcv/src/demo/kotlin/DemoResize02.kt

@@ -3,17 +3,29 @@ import org.openrndr.boofcv.binding.resizeTo
 import org.openrndr.color.ColorRGBa
 import org.openrndr.draw.loadImage
 
+/**
+ * Demonstrates how to scale down images using the `resizeTo` BoofCV-based
+ * method.
+ *
+ * If only the `newWidth` or the `newHeight` arguments are specified,
+ * the resizing happens maintaining the original aspect ratio.
+ */
 fun main() = application {
     program {
-        // Load an image, convert to BoofCV format using orx-boofcv
         val input = loadImage("demo-data/images/image-001.png")
+
         val scaled = input.resizeTo(input.width / 3)
         val scaled2 = input.resizeTo(newHeight = input.height / 4, convertToGray = true)
         val scaled3 = input.resizeTo(input.width / 5, input.height / 5)
 
+        println("${input.width} x ${input.height}")
+        println("${scaled.width} x ${scaled.height}")
+
         extend {
             drawer.clear(ColorRGBa.BLACK)
             drawer.translate(0.0, (height - scaled.bounds.height) / 2.0)
+
+            // Display actually scaled down versions of the loaded image
             drawer.image(scaled)
             drawer.image(scaled2, scaled.bounds.width, scaled.bounds.height - scaled2.height)
             drawer.image(scaled3, scaled.bounds.width + scaled2.bounds.width, scaled.bounds.height - scaled3.height)

orx-jvm/orx-boofcv/src/demo/kotlin/DemoSimplified01.kt

@@ -17,6 +17,18 @@ import org.openrndr.math.Vector2
 import org.openrndr.shape.Rectangle
 import org.openrndr.shape.ShapeContour
 
+/**
+ * When converting a `ColorBuffer` to `ShapeContour` instances using
+ * `BoofCV`, simple shapes can have hundreds of segments and vertices.
+ *
+ * This demo shows how to use the `simplify()` method to greatly
+ * reduce the number of vertices.
+ *
+ * Then it uses the simplified vertex lists to create smooth curves
+ * (using `CatmullRomChain2`) and polygonal curves (using `ShapeContour.fromPoints`).
+ *
+ * Study the console to learn about the number of segments before and after simplification.
+ */
 fun main() = application {
     program {
         // Create a buffer where to draw something for boofcv
@@ -41,6 +53,7 @@ fun main() = application {
             rectangle(0.0, -200.0, 60.0, 60.0)
             circle(0.0, 190.0, 60.0)
         }
+
         // Convert the bitmap buffer into ShapeContours
         val vectorized = imageToContours(rt.colorBuffer(0))
 
@@ -73,8 +86,11 @@ fun main() = application {
         extend {
             drawer.run {
                 fill = null // ColorRGBa.PINK.opacify(0.15)
+
                 stroke = ColorRGBa.PINK.opacify(0.7)
                 contours(polygonal)
+
+                stroke = ColorRGBa.GREEN.opacify(0.7)
                 contours(smooth)
             }
         }

orx-jvm/orx-gui/README.md

@@ -178,7 +178,10 @@ import org.openrndr.extra.parameters.DoubleParameter
 ## Demos
 ### DemoAppearance01
 
-A simple demonstration of a GUI for drawing some circles
+Demonstrates how to customize the appearance of the GUI by using
+`GUIAppearance()`.
+
+In this demo, we make the GUI wider (400 pixels) and translucent.
 
 ![DemoAppearance01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-gui/images/DemoAppearance01Kt.png)
 
@@ -186,7 +189,7 @@ A simple demonstration of a GUI for drawing some circles
 
 ### DemoHide01
 
-A simple demonstration of a GUI for drawing some circles
+Demonstrates how to hide the GUI when the mouse pointer is outside of it.
 
 ![DemoHide01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-gui/images/DemoHide01Kt.png)
 
@@ -194,15 +197,38 @@ A simple demonstration of a GUI for drawing some circles
 
 ### DemoOptions01
 
-A simple demonstration of a GUI with a drop down menu
+A simple demonstration of a GUI with a drop-down menu.
+
+The entries in the drop-down menu are taken from an `enum class`.
 
 ![DemoOptions01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-gui/images/DemoOptions01Kt.png)
 
 [source code](src/demo/kotlin/DemoOptions01.kt)
 
+### DemoOptions02
+
+A simple demonstration of a GUI with a drop-down menu.
+
+The entries in the drop-down menu are taken from an `enum class`.
+The `enum class` entries contain both a name (used in the drop-down)
+and a `ColorRGBa` instance (used for rendering).
+
+![DemoOptions02Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-gui/images/DemoOptions02Kt.png)
+
+[source code](src/demo/kotlin/DemoOptions02.kt)
+
 ### DemoPath01
 
+Demonstrates how to include a button for loading images in a GUI, and how to display
+the loaded image.
 
+The program applies the `@PathParameter` annotation to a `String` variable, which gets
+rendered by the GUI as an image-picker button. Note the allowed file `extensions`.
+
+This mechanism only updates the `String` containing the path of an image file.
+
+The `watchingImagePath()` delegate property is used to automatically load an image
+when its `String` argument changes.
 
 ![DemoPath01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-gui/images/DemoPath01Kt.png)
 
@@ -210,9 +236,11 @@ A simple demonstration of a GUI with a drop down menu
 
 ### DemoPresets01
 
-Shows how to store and retrieve in-memory gui presets.
+Shows how to store and retrieve in-memory GUI presets,
+each containing two integer values and two colors.
+
 Keyboard controls:
-[Left Shift] + [0]..[9] => store current gui values to a preset
+[Left Shift] + [0]..[9] => store current GUI values to a preset
 [0]..[9] => recall a preset
 
 ![DemoPresets01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-gui/images/DemoPresets01Kt.png)
@@ -221,7 +249,17 @@ Keyboard controls:
 
 ### DemoSideCanvas01
 
-A simple demonstration of a GUI for drawing some circles
+Demonstrates the `GUI.enableSideCanvas` feature.
+
+When set to true, the `GUI` provides a `canvas` property where one can draw.
+The size of this canvas is the window size minus the GUI size.
+
+That's why if we draw a circle at `drawer.width / 2.0` it is centered
+on the `canvas`, not on the window.
+
+This demo sets the window to resizable, so if you resize the window
+you should see tha the circle stays at the center of the canvas.
+
 
 ![DemoSideCanvas01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-gui/images/DemoSideCanvas01Kt.png)
 
@@ -229,7 +267,15 @@ A simple demonstration of a GUI for drawing some circles
 
 ### DemoSimple01
 
-A simple demonstration of a GUI for drawing some circles
+Demonstrates how to create a simple GUI with 4 inputs:
+- A `ColorParameter` which creates a color picker.
+- A `DoubleParameter` to control the radius of a circle.
+- A `Vector2Parameter` to set the position of that circle.
+- A `DoubleListParameter` which sets the radii of six circles.
+
+The demo also shows how to use the variables controlled by the GUI
+inside the program, so changes to those variables affect
+the rendering in real time.
 
 ![DemoSimple01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-gui/images/DemoSimple01Kt.png)
 
@@ -237,6 +283,10 @@ A simple demonstration of a GUI for drawing some circles
 
 ### DemoXYParameter
 
+Demonstrates the use of the `@XYParameter` annotation applied to a `Vector2` variable.
+
+This annotation creates an interactive XY control in a GUI that can be used to update
+a `Vector2` variable. In this demo it sets the position of a circle.
 
 
 ![DemoXYParameterKt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-gui/images/DemoXYParameterKt.png)

orx-jvm/orx-gui/src/demo/kotlin/DemoAppearance01.kt

@@ -7,7 +7,10 @@ import org.openrndr.math.Vector2
 import org.openrndr.shape.Circle
 
 /**
- * A simple demonstration of a GUI for drawing some circles
+ * Demonstrates how to customize the appearance of the GUI by using
+ * `GUIAppearance()`.
+ *
+ * In this demo, we make the GUI wider (400 pixels) and translucent.
  */
 fun main() = application {
     program {

orx-jvm/orx-gui/src/demo/kotlin/DemoHide01.kt

@@ -6,7 +6,7 @@ import org.openrndr.math.Vector2
 import org.openrndr.shape.Circle
 
 /**
- * A simple demonstration of a GUI for drawing some circles
+ * Demonstrates how to hide the GUI when the mouse pointer is outside of it.
  */
 fun main() = application {
     program {
@@ -29,7 +29,7 @@ fun main() = application {
         gui.add(settings)
         extend(gui)
 
-        // note we can only change the visibility after the extend
+        // note we can only change the visibility after the `extend`
         gui.visible = false
 
         extend {

orx-jvm/orx-gui/src/demo/kotlin/DemoMultiWindow01.kt

@@ -6,7 +6,7 @@ import org.openrndr.window
 import kotlin.system.exitProcess
 
 /**
- * Demonstration of multi window GUI in the manual way
+ * Demonstration of a multi window GUI in the manual way
  */
 fun main() {
     // skip this demo on CI

orx-jvm/orx-gui/src/demo/kotlin/DemoMultiWindow02.kt

@@ -4,7 +4,7 @@ import org.openrndr.extra.parameters.DoubleParameter
 import kotlin.system.exitProcess
 
 /**
- * Demonstration of multi window GUI using WindowedGUI extension
+ * Demonstration of a multi window GUI using the `WindowedGUI` extension
  */
 fun main() {
     // skip this demo on CI

orx-jvm/orx-gui/src/demo/kotlin/DemoOptions01.kt

@@ -5,7 +5,9 @@ import org.openrndr.extra.parameters.Description
 import org.openrndr.extra.parameters.OptionParameter
 
 /**
- * A simple demonstration of a GUI with a drop down menu
+ * A simple demonstration of a GUI with a drop-down menu.
+ *
+ * The entries in the drop-down menu are taken from an `enum class`.
  */
 
 enum class BackgroundColors {
@@ -15,6 +17,10 @@ enum class BackgroundColors {
 }
 
 fun main() = application {
+    configure {
+        width = 720
+        height = 360
+    }
     program {
         val gui = GUI()
         gui.compartmentsCollapsedByDefault = false

orx-jvm/orx-gui/src/demo/kotlin/DemoOptions02.kt

@@ -0,0 +1,43 @@
+import org.openrndr.application
+import org.openrndr.color.ColorRGBa
+import org.openrndr.extra.gui.GUI
+import org.openrndr.extra.parameters.Description
+import org.openrndr.extra.parameters.OptionParameter
+
+/**
+ * A simple demonstration of a GUI with a drop-down menu.
+ *
+ * The entries in the drop-down menu are taken from an `enum class`.
+ * The `enum class` entries contain both a name (used in the drop-down)
+ * and a `ColorRGBa` instance (used for rendering).
+ */
+
+enum class BackgroundColors2(val color: ColorRGBa) {
+    Pink(ColorRGBa.PINK),
+    Black(ColorRGBa.BLACK),
+    Yellow(ColorRGBa.YELLOW)
+}
+
+fun main() = application {
+    configure {
+        width = 720
+        height = 360
+    }
+    program {
+        val gui = GUI()
+        gui.compartmentsCollapsedByDefault = false
+        val settings = @Description("Settings") object {
+            @OptionParameter("Background color")
+            var option = BackgroundColors2.Pink
+        }
+
+        gui.add(settings)
+        extend(gui)
+        gui.onChange { name, value ->
+            println("$name: $value")
+        }
+        extend {
+            drawer.clear(settings.option.color)
+        }
+    }
+}

orx-jvm/orx-gui/src/demo/kotlin/DemoPath01.kt

@@ -4,6 +4,18 @@ import org.openrndr.extra.parameters.Description
 import org.openrndr.extra.parameters.PathParameter
 import org.openrndr.extra.propertywatchers.watchingImagePath
 
+/**
+ * Demonstrates how to include a button for loading images in a GUI, and how to display
+ * the loaded image.
+ *
+ * The program applies the `@PathParameter` annotation to a `String` variable, which gets
+ * rendered by the GUI as an image-picker button. Note the allowed file `extensions`.
+ *
+ * This mechanism only updates the `String` containing the path of an image file.
+ *
+ * The `watchingImagePath()` delegate property is used to automatically load an image
+ * when its `String` argument changes.
+ */
 fun main() = application {
     program {
         val gui = GUI()

orx-jvm/orx-gui/src/demo/kotlin/DemoPresets01.kt

@@ -7,12 +7,18 @@ import org.openrndr.extra.parameters.Description
 import org.openrndr.extra.parameters.IntParameter
 
 /**
- * Shows how to store and retrieve in-memory gui presets.
+ * Shows how to store and retrieve in-memory GUI presets,
+ * each containing two integer values and two colors.
+ *
  * Keyboard controls:
- * [Left Shift] + [0]..[9] => store current gui values to a preset
+ * [Left Shift] + [0]..[9] => store current GUI values to a preset
  *                [0]..[9] => recall a preset
  */
 fun main() = application {
+    configure {
+        width = 720
+        height = 480
+    }
     program {
         val gui = GUI()
         gui.compartmentsCollapsedByDefault = false
@@ -43,9 +49,9 @@ fun main() = application {
             // Draw a pattern based on modulo
             for (i in 0 until 100) {
                 if (i % settings.a == 0 || i % settings.b == 0) {
-                    val x = (i % 10) * 64.0
+                    val x = (i % 10) * 72.0
                     val y = (i / 10) * 48.0
-                    drawer.rectangle(x, y, 64.0, 48.0)
+                    drawer.rectangle(x, y, 72.0, 48.0)
                 }
             }
         }

orx-jvm/orx-gui/src/demo/kotlin/DemoSideCanvas01.kt

@@ -2,18 +2,29 @@ import org.openrndr.application
 import org.openrndr.color.ColorRGBa
 import org.openrndr.extra.gui.GUI
 import org.openrndr.extra.gui.GUIAppearance
-import org.openrndr.extra.parameters.*
-import org.openrndr.math.Vector2
+import org.openrndr.extra.parameters.ColorParameter
+import org.openrndr.extra.parameters.Description
+import org.openrndr.extra.parameters.DoubleParameter
 import org.openrndr.panel.elements.draw
 
 
 /**
- * A simple demonstration of a GUI for drawing some circles
+ * Demonstrates the `GUI.enableSideCanvas` feature.
+ *
+ * When set to true, the `GUI` provides a `canvas` property where one can draw.
+ * The size of this canvas is the window size minus the GUI size.
+ *
+ * That's why if we draw a circle at `drawer.width / 2.0` it is centered
+ * on the `canvas`, not on the window.
+ *
+ * This demo sets the window to resizable, so if you resize the window
+ * you should see tha the circle stays at the center of the canvas.
+ *
  */
 fun main() = application {
     configure {
-        width = 800
-        height = 800
+        width = 720
+        height = 720
         windowResizable = true
     }
 
@@ -23,17 +34,11 @@ fun main() = application {
         gui.enableSideCanvas = true
 
         val settings = @Description("Settings") object {
-            @DoubleParameter("radius", 0.0, 100.0)
+            @DoubleParameter("radius", 0.0, 200.0)
             var radius = 50.0
 
-            @Vector2Parameter("position", 0.0, 1.0)
-            var position = Vector2(0.6, 0.5)
-
             @ColorParameter("color")
             var color = ColorRGBa.PINK
-
-            @DoubleListParameter("radii", 5.0, 30.0)
-            var radii = mutableListOf(5.0, 6.0, 8.0, 14.0, 20.0, 30.0)
         }
         gui.add(settings)
         extend(gui)
@@ -42,7 +47,7 @@ fun main() = application {
             val width = drawer.width
             val height = drawer.height
             drawer.fill = settings.color
-            drawer.circle(width/2.0, height/2.0, 100.0)
+            drawer.circle(width / 2.0, height / 2.0, settings.radius)
         }
     }
 }

orx-jvm/orx-gui/src/demo/kotlin/DemoSimple01.kt

@@ -6,11 +6,22 @@ import org.openrndr.math.Vector2
 import org.openrndr.shape.Circle
 
 /**
- * A simple demonstration of a GUI for drawing some circles
+ * Demonstrates how to create a simple GUI with 4 inputs:
+ * - A `ColorParameter` which creates a color picker.
+ * - A `DoubleParameter` to control the radius of a circle.
+ * - A `Vector2Parameter` to set the position of that circle.
+ * - A `DoubleListParameter` which sets the radii of six circles.
+ *
+ * The demo also shows how to use the variables controlled by the GUI
+ * inside the program, so changes to those variables affect
+ * the rendering in real time.
  */
 fun main() = application {
+    configure {
+        width = 720
+        height = 450
+    }
     program {
-
         val gui = GUI()
         gui.compartmentsCollapsedByDefault = false
 

orx-jvm/orx-gui/src/demo/kotlin/DemoXYParameter.kt

@@ -4,6 +4,13 @@ import org.openrndr.extra.parameters.Description
 import org.openrndr.extra.parameters.XYParameter
 import org.openrndr.math.Vector2
 
+/**
+ * Demonstrates the use of the `@XYParameter` annotation applied to a `Vector2` variable.
+ *
+ * This annotation creates an interactive XY control in a GUI that can be used to update
+ * a `Vector2` variable. In this demo it sets the position of a circle.
+ *
+ */
 fun main() = application {
     configure {
         width = 800

orx-jvm/orx-rabbit-control/README.md

@@ -42,7 +42,15 @@ More info about the web client:
 ## Demos
 ### DemoRabbitControl
 
+Demonstrates how to use RabbitControl to create a web-based user interface for your program.
 
+A `settings` object is created using the same syntax used for `orx-gui`, including
+annotations for different variable types.
+
+The program then passes these `settings` to the `RabbitControlServer`. A QR-code is displayed
+to open the web user interface. A clickable URL is also displayed in the console.
+
+Once the UI is visible in a web browser we can use it to control the OPENRNDR program.
 
 ![DemoRabbitControlKt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-rabbit-control/images/DemoRabbitControlKt.png)
 
@@ -50,7 +58,10 @@ More info about the web client:
 
 ### DemoRabbitControlManualOverlay
 
+Demonstrates how the QR-code pointing at the Rabbit Control web-based user interface
+can be displayed and hidden manually.
 
+To display the QR-code overlay in this demo, hold down the HOME key in the keyboard.
 
 ![DemoRabbitControlManualOverlayKt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-rabbit-control/images/DemoRabbitControlManualOverlayKt.png)
 
@@ -58,6 +69,12 @@ More info about the web client:
 
 ### DemoRabbitHole
 
+Starts the RabbitControlServer with a `Rabbithole` using the key 'orxtest'.
+
+`Rabbithole` allows you to access your exposed parameters from Internet
+connected computers that are not in the same network.
+
+To use it with this example use 'orxtest' as the tunnel-name in https://rabbithole.rabbitcontrol.cc
 
 
 ![DemoRabbitHoleKt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-rabbit-control/images/DemoRabbitHoleKt.png)

orx-jvm/orx-rabbit-control/src/demo/kotlin/DemoRabbitControl.kt

@@ -6,7 +6,17 @@ import org.openrndr.math.Vector2
 import org.openrndr.math.Vector3
 import org.openrndr.math.Vector4
 
-
+/**
+ * Demonstrates how to use RabbitControl to create a web-based user interface for your program.
+ *
+ * A `settings` object is created using the same syntax used for `orx-gui`, including
+ * annotations for different variable types.
+ *
+ * The program then passes these `settings` to the `RabbitControlServer`. A QR-code is displayed
+ * to open the web user interface. A clickable URL is also displayed in the console.
+ *
+ * Once the UI is visible in a web browser we can use it to control the OPENRNDR program.
+ */
 fun main() = application {
     configure {
         width = 800

orx-jvm/orx-rabbit-control/src/demo/kotlin/DemoRabbitControlManualOverlay.kt

@@ -4,6 +4,12 @@ import org.openrndr.color.ColorRGBa
 import org.openrndr.extra.parameters.BooleanParameter
 
 
+/**
+ * Demonstrates how the QR-code pointing at the Rabbit Control web-based user interface
+ * can be displayed and hidden manually.
+ *
+ * To display the QR-code overlay in this demo, hold down the HOME key in the keyboard.
+ */
 fun main() = application {
     configure {
         width = 800

orx-jvm/orx-rabbit-control/src/demo/kotlin/DemoRabbitHole.kt

@@ -6,7 +6,15 @@ import org.openrndr.math.Vector2
 import org.openrndr.math.Vector3
 import org.openrndr.math.Vector4
 
-
+/**
+ * Starts the RabbitControlServer with a `Rabbithole` using the key 'orxtest'.
+ *
+ * `Rabbithole` allows you to access your exposed parameters from Internet
+ * connected computers that are not in the same network.
+ *
+ * To use it with this example use 'orxtest' as the tunnel-name in https://rabbithole.rabbitcontrol.cc
+ *
+ */
 fun main() = application {
     configure {
         width = 800
@@ -14,13 +22,6 @@ fun main() = application {
     }
 
     program {
-        /**
-         * Start RabbitControlServer with a Rabbithole with key 'orxtest'
-         * Please visit https://rabbithole.rabbitcontrol.cc for more information.
-         *
-         * Rabbithole allows you to access your exposed parameter from the internet.
-         * To use it with this example just use 'orxtest' as tunnel-name on the main page.
-         */
         val rabbit = RabbitControlServer(false, 10000, 8080, "wss://rabbithole.rabbitcontrol.cc/public/rcpserver/connect?key=orxtest")
         val font = loadFont("demo-data/fonts/IBMPlexMono-Regular.ttf", 20.0)
         val settings = object {

orx-mesh-generators/README.md

@@ -105,7 +105,15 @@ Demonstrate decal generation and rendering
 
 ### DemoAll
 
+Demonstrates how to create various types of 3D meshes:
+box, sphere, dodecahedron, cylinder, plane, cap and resolve.
 
+Two textures are used: one generative with gradients, and the second
+one is an image loaded from disk. The horizontal mouse position is used
+to select which of the two textures to use.
+
+The meshes are positioned in space using a 2D mesh, and displayed
+rotating on the X and Y axes at different speeds.
 
 ![DemoAllKt](https://raw.githubusercontent.com/openrndr/orx/media/orx-mesh-generators/images/DemoAllKt.png)
 
@@ -113,6 +121,18 @@ Demonstrate decal generation and rendering
 
 ### DemoBox
 
+Demonstrates how to create a 3D mesh box by specifying its width, height and depth.
+
+The `box` is a `VertexBuffer` and contains texture coordinates which can be
+used to apply a texture to its faces.
+
+After creating the box, the program creates a texture with a gradient.
+In it, the red component increases along the x-axis and the green component
+along the y-axis.
+
+The scene is rendered with an interactive `Orbital` 3D camera.
+
+A shade style is used to apply the texture to the box.
 
 
 ![DemoBoxKt](https://raw.githubusercontent.com/openrndr/orx/media/orx-mesh-generators/images/DemoBoxKt.png)
@@ -121,7 +141,15 @@ Demonstrate decal generation and rendering
 
 ### DemoComplex01
 
+Demonstrates how to use `buildTriangleMesh` to construct composite 3D meshes.
 
+A DSL allows specifying the color and transformations of each mesh, in this case,
+of a sphere and a box.
+
+An interactive 3D Orbital camera is defined, specifying the location of its `eye` and
+`lookAt` properties.
+
+A minimal shade style is used to simulate a uni-directional light pointing along the view Z axis.
 
 ![DemoComplex01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-mesh-generators/images/DemoComplex01Kt.png)
 
@@ -129,7 +157,7 @@ Demonstrate decal generation and rendering
 
 ### DemoComplex02
 
-
+Demonstrates the creation of a 3D mesh composed of two hemispheres, a cylinder and 12 legs.
 
 ![DemoComplex02Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-mesh-generators/images/DemoComplex02Kt.png)
 
@@ -137,7 +165,14 @@ Demonstrate decal generation and rendering
 
 ### DemoComplex03
 
+Demonstrates the creation of a 3D mesh composed of two hemispheres, a cylinder and 12 legs.
+Additionally, the body of the shape features 5 ridges on the sides
+of the cylinder.
 
+The code reveals DSL keywords under `buildTriangleMesh`
+affecting transformation matrices, for instance `isolated`, `translate` and `rotate`,
+and mesh generating keywords like
+`hemisphere`, `taperedCylinder` and `cylinder`.
 
 ![DemoComplex03Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-mesh-generators/images/DemoComplex03Kt.png)
 
@@ -145,7 +180,9 @@ Demonstrate decal generation and rendering
 
 ### DemoComplex04
 
-
+Demonstrates the use of `buildTriangleMesh` to create
+a composite 3D mesh and introduces a new mesh generating keyword:
+`cap`.
 
 ![DemoComplex04Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-mesh-generators/images/DemoComplex04Kt.png)
 
@@ -153,6 +190,9 @@ Demonstrate decal generation and rendering
 
 ### DemoComplex05
 
+Demonstrates how to create a 3D grid of extruded shapes
+(short cylinders), then applies three 3D twists to the
+composition to deform it.
 
 
 ![DemoComplex05Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-mesh-generators/images/DemoComplex05Kt.png)
@@ -161,8 +201,11 @@ Demonstrate decal generation and rendering
 
 ### DemoComplex06
 
-Generates a grid of grids of boxes.
-Interactive orbital camera.
+Generates a grid of grids of 3D boxes using `buildTriangleMesh` and
+renders them using an interactive orbital camera.
+
+The cubes ar colorized using a shade style that sets colors based
+on vertex positions in space, converting XYZ coordinates into RGB colors.
 
 
 ![DemoComplex06Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-mesh-generators/images/DemoComplex06Kt.png)
@@ -270,7 +313,13 @@ for a radial-symmetry effect.
 
 ### tangents/DemoTangents01
 
+Tangent and bitangent vectors are used in shader programs for tangent space normal mapping / lighting
+and certain forms of displacement mapping.
 
+This demo shows:
+- how to create a triangulated `MeshData`.
+- how to estimate the tangents of this MeshData.
+- How to use the tangent and bitangent attributes in GLSL code.
 
 ![tangents-DemoTangents01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-mesh-generators/images/tangents-DemoTangents01Kt.png)
 

orx-mesh-generators/src/jvmDemo/kotlin/DemoAll.kt

@@ -8,6 +8,17 @@ import org.openrndr.math.Vector2
 import org.openrndr.math.Vector3
 import org.openrndr.shape.Rectangle
 
+/**
+ * Demonstrates how to create various types of 3D meshes:
+ * box, sphere, dodecahedron, cylinder, plane, cap and resolve.
+ *
+ * Two textures are used: one generative with gradients, and the second
+ * one is an image loaded from disk. The horizontal mouse position is used
+ * to select which of the two textures to use.
+ *
+ * The meshes are positioned in space using a 2D mesh, and displayed
+ * rotating on the X and Y axes at different speeds.
+ */
 fun main() = application {
     configure {
         width = 720

orx-mesh-generators/src/jvmDemo/kotlin/DemoBox.kt

@@ -9,6 +9,21 @@ import org.openrndr.extra.camera.Orbital
 import org.openrndr.extra.meshgenerators.boxMesh
 import org.openrndr.math.Vector3
 
+/**
+ * Demonstrates how to create a 3D mesh box by specifying its width, height and depth.
+ *
+ * The `box` is a `VertexBuffer` and contains texture coordinates which can be
+ * used to apply a texture to its faces.
+ *
+ * After creating the box, the program creates a texture with a gradient.
+ * In it, the red component increases along the x-axis and the green component
+ * along the y-axis.
+ *
+ * The scene is rendered with an interactive `Orbital` 3D camera.
+ *
+ * A shade style is used to apply the texture to the box.
+ *
+ */
 fun main() = application {
     configure {
         width = 720

orx-mesh-generators/src/jvmDemo/kotlin/DemoComplex01.kt

@@ -9,6 +9,17 @@ import org.openrndr.extra.meshgenerators.buildTriangleMesh
 import org.openrndr.extra.meshgenerators.sphere
 import org.openrndr.math.Vector3
 
+/**
+ * Demonstrates how to use `buildTriangleMesh` to construct composite 3D meshes.
+ *
+ * A DSL allows specifying the color and transformations of each mesh, in this case,
+ * of a sphere and a box.
+ *
+ * An interactive 3D Orbital camera is defined, specifying the location of its `eye` and
+ * `lookAt` properties.
+ *
+ * A minimal shade style is used to simulate a uni-directional light pointing along the view Z axis.
+ */
 fun main() = application {
     configure {
         width = 720

orx-mesh-generators/src/jvmDemo/kotlin/DemoComplex02.kt

@@ -8,6 +8,9 @@ import org.openrndr.extra.meshgenerators.cylinder
 import org.openrndr.extra.meshgenerators.hemisphere
 import org.openrndr.math.Vector3
 
+/**
+ * Demonstrates the creation of a 3D mesh composed of two hemispheres, a cylinder and 12 legs.
+ */
 fun main() = application {
     configure {
         width = 720

orx-mesh-generators/src/jvmDemo/kotlin/DemoComplex03.kt

@@ -6,6 +6,16 @@ import org.openrndr.extra.camera.Orbital
 import org.openrndr.extra.meshgenerators.*
 import org.openrndr.math.Vector3
 
+/**
+ * Demonstrates the creation of a 3D mesh composed of two hemispheres, a cylinder and 12 legs.
+ * Additionally, the body of the shape features 5 ridges on the sides
+ * of the cylinder.
+ *
+ * The code reveals DSL keywords under `buildTriangleMesh`
+ * affecting transformation matrices, for instance `isolated`, `translate` and `rotate`,
+ * and mesh generating keywords like
+ * `hemisphere`, `taperedCylinder` and `cylinder`.
+ */
 fun main() = application {
     configure {
         width = 720

orx-mesh-generators/src/jvmDemo/kotlin/DemoComplex04.kt

@@ -7,6 +7,11 @@ import org.openrndr.extra.meshgenerators.*
 import org.openrndr.math.Vector2
 import org.openrndr.math.Vector3
 
+/**
+ * Demonstrates the use of `buildTriangleMesh` to create
+ * a composite 3D mesh and introduces a new mesh generating keyword:
+ * `cap`.
+ */
 fun main() = application {
     configure {
         width = 720

orx-mesh-generators/src/jvmDemo/kotlin/DemoComplex05.kt

@@ -11,6 +11,12 @@ import org.openrndr.extra.meshgenerators.twist
 import org.openrndr.math.Vector3
 import org.openrndr.shape.Circle
 
+/**
+ * Demonstrates how to create a 3D grid of extruded shapes
+ * (short cylinders), then applies three 3D twists to the
+ * composition to deform it.
+ *
+ */
 fun main() = application {
     configure {
         width = 720

orx-mesh-generators/src/jvmDemo/kotlin/DemoComplex06.kt

@@ -9,8 +9,11 @@ import org.openrndr.extra.noise.simplex
 import org.openrndr.math.Vector3
 
 /**
- * Generates a grid of grids of boxes.
- * Interactive orbital camera.
+ * Generates a grid of grids of 3D boxes using `buildTriangleMesh` and
+ * renders them using an interactive orbital camera.
+ *
+ * The cubes ar colorized using a shade style that sets colors based
+ * on vertex positions in space, converting XYZ coordinates into RGB colors.
  *
  */
 fun main() = application {

orx-mesh-generators/src/jvmDemo/kotlin/tangents/DemoTangents01.kt

@@ -10,6 +10,15 @@ import org.openrndr.extra.objloader.loadOBJMeshData
 import org.openrndr.math.Vector3
 import java.io.File
 
+/**
+ * Tangent and bitangent vectors are used in shader programs for tangent space normal mapping / lighting
+ * and certain forms of displacement mapping.
+ *
+ * This demo shows:
+ * - how to create a triangulated `MeshData`.
+ * - how to estimate the tangents of this MeshData.
+ * - How to use the tangent and bitangent attributes in GLSL code.
+ */
 fun main() = application {
     configure {
         width = 720
@@ -34,7 +43,6 @@ fun main() = application {
                     //x_fill.rgb = normalize(viewTangent) * 0.5 + 0.5;
                     x_fill.rgb = vec3(c); 
                     """.trimIndent()
-
             }
 
             drawer.vertexBuffer(objVB, DrawPrimitive.TRIANGLES)

orx-shapes/README.md

@@ -465,6 +465,31 @@ to round contours with linear segments.
 
 [source code](src/jvmDemo/kotlin/hobbycurve/DemoHobbyCurve03.kt)
 
+### hobbycurve/DemoHobbyCurve04
+
+Demonstrates the use of the `tensions` argument when creating a Hobby curve.
+
+The program starts by creating a random set of scattered points with enough separation between them.
+The points are sorted using `hilbertOrder` to minimize the travel distance when visiting all the points.
+Finally, we draw a set of 40 hobby translucent curves using those same points but with varying tensions.
+
+![hobbycurve-DemoHobbyCurve04Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-shapes/images/hobbycurve-DemoHobbyCurve04Kt.png)
+
+[source code](src/jvmDemo/kotlin/hobbycurve/DemoHobbyCurve04.kt)
+
+### hobbycurve/DemoHobbyCurve05
+
+Demonstrates the creation of a 40 hobby curves with 10 points each.
+The control points in all hobby curves are almost identical, varying only
+due to a slight increase in one of the arguments of a simplex noise call.
+
+The program shows that minor displacements in control points can have
+a large impact in the resulting curve.
+
+![hobbycurve-DemoHobbyCurve05Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-shapes/images/hobbycurve-DemoHobbyCurve05Kt.png)
+
+[source code](src/jvmDemo/kotlin/hobbycurve/DemoHobbyCurve05.kt)
+
 ### hobbycurve/DemoHobbyCurve3D01
 
 Demonstrates how to use the 3D implementation of the `hobbyCurve` method, to draw a smooth curve passing
@@ -678,6 +703,22 @@ Demonstrate rectangle-rectangle intersection
 
 [source code](src/jvmDemo/kotlin/primitives/DemoRectangleIntersection01.kt)
 
+### primitives/DemoRectangleIrregularGrid02
+
+Demonstrates how to use `Rectangle.irregularGrid()` to create a grid with varying column widths
+and row heights. The widths and heights are specified as a list of 13 `Double` values, each
+picked randomly between the values 1.0 and 4.0. This produces two types of columns and two
+types of rows only: wide ones and narrow ones.
+
+The program also demonstrates how to query a `row()` and a `column()` from a `RectangleGrid` instance,
+both of which return a `List<Rectangle>`. Both `Rectangle` lists are rendered with translucent
+colors, which makes the intersection of the column and the row slightly brighter.
+
+
+![primitives-DemoRectangleIrregularGrid02Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-shapes/images/primitives-DemoRectangleIrregularGrid02Kt.png)
+
+[source code](src/jvmDemo/kotlin/primitives/DemoRectangleIrregularGrid02.kt)
+
 ### primitives/DemoRectangleIrregularGrid
 
 
@@ -749,6 +790,21 @@ This serves as a demonstration of positioning and rendering shapes in a structur
 
 [source code](src/jvmDemo/kotlin/primitives/DemoTear01.kt)
 
+### primitives/DemoTear02
+
+Demonstrates the use of `Tear()` to create drop-like shapes out of a Vector2 point and a Circle.
+
+The tear locations are calculated using the `Rectangle.scatter()` function. Locations near the
+center of the window are filtered out.
+
+The radii of each tear is randomly chosen between three values. The orientation of each tear
+is calculated by getting the normalized difference between the tear and the center of the window,
+making them look as being emitted at the center of the window.
+
+![primitives-DemoTear02Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-shapes/images/primitives-DemoTear02Kt.png)
+
+[source code](src/jvmDemo/kotlin/primitives/DemoTear02.kt)
+
 ### rectify/DemoRectifiedContour01
 
 

orx-shapes/src/jvmDemo/kotlin/hobbycurve/DemoHobbyCurve04.kt

@@ -0,0 +1,38 @@
+package hobbycurve
+
+import org.openrndr.application
+import org.openrndr.color.ColorRGBa
+import org.openrndr.extra.noise.scatter
+import org.openrndr.extra.shapes.hobbycurve.hobbyCurve
+import org.openrndr.extra.shapes.ordering.hilbertOrder
+import kotlin.random.Random
+
+/**
+ * Demonstrates the use of the `tensions` argument when creating a Hobby curve.
+ *
+ * The program starts by creating a random set of scattered points with enough separation between them.
+ * The points are sorted using `hilbertOrder` to minimize the travel distance when visiting all the points.
+ * Finally, we draw a set of 40 hobby translucent curves using those same points but with varying tensions.
+ */
+fun main() = application {
+    configure {
+        width = 720
+        height = 720
+    }
+    program {
+        extend {
+            for (i in -20..20) {
+                val t = i / 10.0
+                val points = drawer.bounds.offsetEdges(-50.0)
+                    .scatter(25.0, random = Random(0))
+                    .hilbertOrder()
+
+                drawer.stroke = ColorRGBa.WHITE.opacify(0.5)
+                drawer.fill = null
+                drawer.contour(hobbyCurve(points, closed = false, tensions = { i, inAngle, outAngle ->
+                    Pair(t, t)
+                }))
+            }
+        }
+    }
+}

orx-shapes/src/jvmDemo/kotlin/hobbycurve/DemoHobbyCurve05.kt

@@ -0,0 +1,38 @@
+package hobbycurve
+
+import org.openrndr.application
+import org.openrndr.color.ColorRGBa
+import org.openrndr.extra.color.presets.WHITE_SMOKE
+import org.openrndr.extra.noise.simplex
+import org.openrndr.extra.noise.uniform
+import org.openrndr.extra.shapes.hobbycurve.hobbyCurve
+import org.openrndr.extra.shapes.ordering.hilbertOrder
+import org.openrndr.math.Vector2
+
+/**
+ * Demonstrates the creation of a 40 hobby curves with 10 points each.
+ * The control points in all hobby curves are almost identical, varying only
+ * due to a slight increase in one of the arguments of a simplex noise call.
+ *
+ * The program shows that minor displacements in control points can have
+ * a large impact in the resulting curve.
+ */
+fun main() = application {
+    program {
+        val seed = 68040
+        val curves = List(40) { n ->
+            hobbyCurve(List(10) {
+                Vector2(
+                    simplex(seed, it * 13.3, n * 0.001) * 300.0 + 320.0,
+                    simplex(seed / 2, it * 77.4, n * 0.001) * 300.0 + 240.0
+                )
+            }.hilbertOrder(), true)
+        }
+        extend {
+            drawer.clear(ColorRGBa.WHITE_SMOKE)
+            drawer.fill = null
+            drawer.stroke = ColorRGBa.BLACK.opacify(0.3)
+            drawer.contours(curves)
+        }
+    }
+}

orx-shapes/src/jvmDemo/kotlin/primitives/DemoRectangleIrregularGrid02.kt

@@ -0,0 +1,47 @@
+package primitives
+
+import org.openrndr.application
+import org.openrndr.color.ColorRGBa
+import org.openrndr.extra.color.presets.CORAL
+import org.openrndr.extra.shapes.primitives.column
+import org.openrndr.extra.shapes.primitives.irregularGrid
+import org.openrndr.extra.shapes.primitives.row
+import kotlin.random.Random
+
+/**
+ * Demonstrates how to use `Rectangle.irregularGrid()` to create a grid with varying column widths
+ * and row heights. The widths and heights are specified as a list of 13 `Double` values, each
+ * picked randomly between the values 1.0 and 4.0. This produces two types of columns and two
+ * types of rows only: wide ones and narrow ones.
+ *
+ * The program also demonstrates how to query a `row()` and a `column()` from a `RectangleGrid` instance,
+ * both of which return a `List<Rectangle>`. Both `Rectangle` lists are rendered with translucent
+ * colors, which makes the intersection of the column and the row slightly brighter.
+ *
+ */
+fun main() = application {
+    configure {
+        width = 720
+        height = 720
+    }
+    program {
+        extend {
+            val r = Random(100)
+            val grid = drawer.bounds.irregularGrid(
+                List(13) { listOf(1.0, 4.0).random(r) },
+                List(13) { listOf(1.0, 4.0).random(r) }
+            )
+
+            drawer.fill = null
+            drawer.stroke = ColorRGBa.WHITE
+            drawer.rectangles(grid.flatten())
+
+            drawer.stroke = ColorRGBa.BLACK
+            drawer.fill = ColorRGBa.PINK.opacify(0.5)
+            drawer.rectangles(grid.column(2))
+
+            drawer.fill = ColorRGBa.CORAL.opacify(0.5)
+            drawer.rectangles(grid.row(6))
+        }
+    }
+}

orx-shapes/src/jvmDemo/kotlin/primitives/DemoTear02.kt

@@ -0,0 +1,42 @@
+package primitives
+
+import org.openrndr.application
+import org.openrndr.color.ColorRGBa
+import org.openrndr.extra.noise.scatter
+import org.openrndr.extra.shapes.primitives.Tear
+import org.openrndr.shape.Circle
+
+/**
+ * Demonstrates the use of `Tear()` to create drop-like shapes out of a Vector2 point and a Circle.
+ *
+ * The tear locations are calculated using the `Rectangle.scatter()` function. Locations near the
+ * center of the window are filtered out.
+ *
+ * The radii of each tear is randomly chosen between three values. The orientation of each tear
+ * is calculated by getting the normalized difference between the tear and the center of the window,
+ * making them look as being emitted at the center of the window.
+ */
+fun main() = application {
+    configure {
+        width = 720
+        height = 720
+    }
+    program {
+        val points = drawer.bounds.scatter(40.0, distanceToEdge = 80.0).filter {
+            it.distanceTo(drawer.bounds.center) > 80.0
+        }
+
+        val tears = points.map {
+            val radius = listOf(5.0, 10.0, 20.0).random()
+            val offset = (it - drawer.bounds.center).normalized * radius
+            Tear(it - offset, Circle(it + offset, radius))
+        }
+
+        extend {
+            drawer.clear(ColorRGBa.WHITE)
+            drawer.fill = ColorRGBa.PINK
+            drawer.stroke = ColorRGBa.BLACK
+            drawer.contours(tears.map { it.contour })
+        }
+    }
+}

orx-timer/README.md

@@ -37,6 +37,11 @@ Note that drawing inside the `repeat` action has no effect. Have a look at the d
 ## Demos
 ### DemoRepeat01
 
+A simple demonstration on using the `repeat` method to execute a function
+at regular intervals.
+
+Note that drawing inside the repeat action has no effect.
+See DemoRepeat02.kt to learn how to trigger drawing.
 
 
 ![DemoRepeat01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-timer/images/DemoRepeat01Kt.png)
@@ -45,14 +50,29 @@ Note that drawing inside the `repeat` action has no effect. Have a look at the d
 
 ### DemoRepeat02
 
-This demonstrates how to combine `repeat {}` with a postponed event to trigger drawing
+This demonstrates how to combine `repeat {}` with a postponed event to trigger drawing.
 
 ![DemoRepeat02Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-timer/images/DemoRepeat02Kt.png)
 
 [source code](src/demo/kotlin/DemoRepeat02.kt)
 
+### DemoRepeat03
+
+Shows how a `repeat` block can update a variable used
+for rendering. In this demo, the `opacity` variable is
+reduced on every animation frame, and increased to 1.0
+every 2 seconds, creating a pulsating animation effect.
+
+![DemoRepeat03Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-timer/images/DemoRepeat03Kt.png)
+
+[source code](src/demo/kotlin/DemoRepeat03.kt)
+
 ### DemoTimeOut01
 
+Demonstrates the `timeOut` function.
+
+It is similar to the `repeat` function,
+but it runs only once after the specified delay in seconds.
 
 
 ![DemoTimeOut01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-timer/images/DemoTimeOut01Kt.png)

orx-timer/src/demo/kotlin/DemoRepeat01.kt

@@ -1,6 +1,14 @@
 import org.openrndr.application
 import org.openrndr.extra.timer.repeat
 
+/**
+ * A simple demonstration on using the `repeat` method to execute a function
+ * at regular intervals.
+ *
+ * Note that drawing inside the repeat action has no effect.
+ * See DemoRepeat02.kt to learn how to trigger drawing.
+ *
+ */
 fun main() = application {
     program {
         repeat(2.0) {

orx-timer/src/demo/kotlin/DemoRepeat02.kt

@@ -4,7 +4,7 @@ import org.openrndr.events.Event
 import org.openrndr.extra.timer.repeat
 
 /**
- * This demonstrates how to combine `repeat {}` with a postponed event to trigger drawing
+ * This demonstrates how to combine `repeat {}` with a postponed event to trigger drawing.
  */
 
 fun main() = application {

orx-timer/src/demo/kotlin/DemoRepeat03.kt

@@ -0,0 +1,25 @@
+import org.openrndr.application
+import org.openrndr.color.ColorRGBa
+import org.openrndr.extra.timer.repeat
+
+/**
+ * Shows how a `repeat` block can update a variable used
+ * for rendering. In this demo, the `opacity` variable is
+ * reduced on every animation frame, and increased to 1.0
+ * every 2 seconds, creating a pulsating animation effect.
+ */
+fun main() = application {
+    program {
+        var opacity = 0.0
+        repeat(2.0) {
+            opacity = 1.0
+        }
+        extend {
+            drawer.clear(ColorRGBa.PINK)
+            drawer.stroke = ColorRGBa.BLACK.opacify(opacity)
+            drawer.fill = ColorRGBa.WHITE.opacify(opacity)
+            drawer.circle(width / 2.0, height / 2.0, 200.0)
+            opacity *= 0.9
+        }
+    }
+}

orx-timer/src/demo/kotlin/DemoTimeOut01.kt

@@ -1,6 +1,13 @@
 import org.openrndr.application
 import org.openrndr.extra.timer.timeOut
 
+/**
+ * Demonstrates the `timeOut` function.
+ *
+ * It is similar to the `repeat` function,
+ * but it runs only once after the specified delay in seconds.
+ *
+ */
 fun main() = application {
     program {
         timeOut(2.0) {

orx-turtle/README.md

@@ -35,7 +35,6 @@ The language also holds some tools to manage the position and orientation of the
 ## Demos
 ### DemoTurtle01
 
-/*
 Drawing a square using the turtle interface.
 
 ![DemoTurtle01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-turtle/images/DemoTurtle01Kt.png)
@@ -44,7 +43,6 @@ Drawing a square using the turtle interface.
 
 ### DemoTurtle02
 
-/*
 A simple random walk made using the turtle interface.
 
 ![DemoTurtle02Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-turtle/images/DemoTurtle02Kt.png)
@@ -53,7 +51,6 @@ A simple random walk made using the turtle interface.
 
 ### DemoTurtle03
 
-/*
 Drawing shape contours aligned to the turtle's orientation.
 
 ![DemoTurtle03Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-turtle/images/DemoTurtle03Kt.png)

settings.gradle.kts

@@ -1,5 +1,3 @@
-import org.gradle.internal.os.OperatingSystem
-
 rootProject.name = "orx"
 
 
@@ -131,3 +129,4 @@ include(":math")
 include(":desktop")
 include(":icegps-common")
 include(":icegps-shared")
+include(":icegps-triangulation")