[orx-shapes] Add demos, tweak comments

orx-shapes/src/commonMain/kotlin/adjust/ContourEdge.kt

@@ -31,10 +31,10 @@ fun <E> List<E>.update(vararg updates: Pair<Int, E>): List<E> {
 
 /**
  * Helper for querying and adjusting [ShapeContour].
- * * An edge embodies exactly the same thing as a [Segment][org.openrndr.shape.Segment]
+ * * An edge embodies exactly the same thing as a [Segment2D][org.openrndr.shape.Segment2D]
  * * All edge operations are immutable and will create a new [ContourEdge] pointing to a copied and updated [ShapeContour]
  * @param contour the contour to be adjusted
- * @param segmentIndex the index of the segment of the contour to be adjusted
+ * @param segmentIndex the index the contour's segment to be adjusted
  * @param adjustments a list of [SegmentOperation] that have been applied to reach to [contour], this is used to inform [ShapeContour]
  * of changes in the contour topology.
  * @since 0.4.4
@@ -126,7 +126,7 @@ data class ContourEdge(
     }
 
     /**
-     * Split the edge in [numberOfParts] parts of equal length
+     * Split the edge in [parts] parts of equal length
      */
     fun splitIn(parts: Int): ContourEdge {
         if (contour.empty || parts < 2) {

orx-shapes/src/jvmDemo/kotlin/adjust/DemoAdjustContour09.kt

@@ -3,7 +3,6 @@ package adjust
 import org.openrndr.application
 import org.openrndr.color.ColorRGBa
 import org.openrndr.draw.loadFont
-import org.openrndr.extra.color.presets.DARK_CYAN
 import org.openrndr.extra.shapes.adjust.adjustContour
 import org.openrndr.extra.shapes.adjust.extensions.averageTangents
 import org.openrndr.extra.shapes.adjust.extensions.switchTangents

orx-shapes/src/jvmDemo/kotlin/alphashape/DemoAlphaShape01.kt

@@ -6,12 +6,18 @@ import org.openrndr.extra.shapes.alphashape.AlphaShape
 import org.openrndr.math.Vector2
 import kotlin.random.Random
 
+/**
+ * Demonstrates the use of [AlphaShape] to create a [org.openrndr.shape.ShapeContour] out
+ * of a collection of random [Vector2] points. Unlike the convex hull, an Alpha shape can be concave.
+ *
+ * More details in [WikiPedia](https://en.wikipedia.org/wiki/Alpha_shape)
+ */
 fun main() = application {
     program {
         val points = List(40) {
             Vector2(
-                Random.nextDouble(width*0.25, width*0.75),
-                Random.nextDouble(height*0.25, height*0.75)
+                Random.nextDouble(width * 0.25, width * 0.75),
+                Random.nextDouble(height * 0.25, height * 0.75)
             )
         }
         val alphaShape = AlphaShape(points)

orx-shapes/src/jvmDemo/kotlin/alphashape/DemoAlphaShape02.kt

@@ -0,0 +1,47 @@
+package alphashape
+
+import org.openrndr.application
+import org.openrndr.color.ColorRGBa
+import org.openrndr.extra.noise.shapes.uniform
+import org.openrndr.extra.shapes.alphashape.AlphaShape
+import org.openrndr.math.Vector2
+import kotlin.random.Random
+
+/**
+ * Demonstrates the use of [AlphaShape] to create ten
+ * [org.openrndr.shape.ShapeContour] instances out of a collection of random [Vector2] points.
+ *
+ * The same points are used for each contour, but an increased alpha parameter
+ * is passed to the AlphaShape algorithm. Higher values return more convex shapes
+ * = shapes with a larger surface.
+ *
+ * The list of shapes is reversed to draw the smaller contours on top, otherwise only
+ * the last one would be visible.
+ *
+ * An instance of [Random] with a fixed seed is used to ensure the resulting
+ * random shape is always the same.
+ */
+fun main() = application {
+    program {
+        val rand = Random(242)
+        val points = List(40) {
+            drawer.bounds.uniform(rand)
+        }
+        val alphaShape = AlphaShape(points)
+        val minAlpha = alphaShape.determineContourAlpha()
+
+        val contours = List(10) {
+            alphaShape.createContour(minAlpha + it * it * it)
+        }.reversed()
+        extend {
+            drawer.stroke = null
+            contours.forEachIndexed { index, contour ->
+                drawer.fill = ColorRGBa.PINK.shade(0.5 + index * 0.07)
+                drawer.contour(contour)
+            }
+
+            drawer.fill = ColorRGBa.WHITE
+            drawer.circles(points, 4.0)
+        }
+    }
+}

orx-shapes/src/jvmDemo/kotlin/operators/DemoRoundCorners02.kt

@@ -0,0 +1,28 @@
+package operators
+
+import org.openrndr.application
+import org.openrndr.extra.shapes.adjust.adjustContour
+import org.openrndr.extra.shapes.operators.roundCorners
+import org.openrndr.shape.Rectangle
+
+fun main() = application {
+    program {
+        extend {
+            val contours = listOf(
+                Rectangle(100.0, 100.0, 100.0, 100.0).contour,
+                adjustContour(Rectangle(400.0, 100.0, 100.0, 100.0).contour) {
+                    selectVertex(0)
+                    vertices.forEach { it.rotate(30.0) }
+                }
+            )
+
+            val contoursRounded = contours.map {
+                it.roundCorners(10.0)
+            }
+
+            drawer.contours(contours)
+            drawer.translate(0.0, 150.0)
+            drawer.contours(contoursRounded)
+        }
+    }
+}