Bumped version to 0.0.12. Added orx-mesh-generators. OPENRNDR 0.3.29

orx-mesh-generators/src/main/kotlin/MeshGenerators.kt

@@ -0,0 +1,104 @@
+package org.openrndr.extras.meshgenerators
+
+import org.openrndr.draw.BufferWriter
+import org.openrndr.draw.VertexBuffer
+import org.openrndr.draw.vertexBuffer
+import org.openrndr.draw.vertexFormat
+import org.openrndr.math.Vector2
+import org.openrndr.math.Vector3
+import org.openrndr.math.mod
+import org.openrndr.shape.Circle
+import org.openrndr.shape.Shape
+import org.openrndr.shape.triangulate
+
+/**
+ * Vertex writer function interface
+ */
+typealias VertexWriter = (position: Vector3, normal: Vector3, texCoord: Vector2) -> Unit
+
+/**
+ * create a [VertexWriter] that writes into a [java.nio.ByteBuffer] through [BufferWriter]
+ */
+fun bufferWriter(bw: BufferWriter): VertexWriter {
+    return { p, n, t ->
+        bw.write(p)
+        bw.write(n)
+        bw.write(t)
+    }
+}
+
+/**
+ * creates a [VertexBuffer] that is suited for holding meshes
+ */
+fun meshVertexBuffer(size: Int): VertexBuffer {
+    return vertexBuffer(vertexFormat {
+        position(3)
+        normal(3)
+        textureCoordinate(2)
+    }, size)
+}
+
+/**
+ * extrudes a [shape] by triangulating it and creating sides and cap geometry
+ * @sample sample
+ */
+fun extrudeShape(shape: Shape, front: Double, back: Double, distanceTolerance: Double = 0.5, writer: VertexWriter) {
+    val baseTriangles = triangulate(shape, distanceTolerance)
+    val depth = back - front
+    val normal = Vector3(0.0, 0.0, depth).normalized
+    val negativeNormal = normal * -1.0
+
+    baseTriangles.forEach {
+        writer(it.vector3(z = front), normal, Vector2.ZERO)
+    }
+    baseTriangles.forEach {
+        writer(it.vector3(z = back), negativeNormal, Vector2.ZERO)
+    }
+
+    shape.contours.forEach {
+        val points = it.adaptivePositions(distanceTolerance)
+
+        val normals = (0 until points.size).map {
+            (points[mod(it+1, points.size)]-points[mod(it-1, points.size)]).safeNormalized
+        }
+
+        val forward = Vector3(0.0, 0.0, depth)
+        val base = Vector3(0.0, 0.0, front)
+
+        (points zip normals).zipWithNext().forEach { (left, right) ->
+            val lnormal = left.second.perpendicular.vector3()
+            val rnormal = right.second.perpendicular.vector3()
+
+            writer(left.first.vector3() + base, lnormal, Vector2.ZERO)
+            writer(right.first.vector3() + base, rnormal, Vector2.ZERO)
+            writer(right.first.vector3() + base + forward, rnormal, Vector2.ZERO)
+
+            writer(right.first.vector3() + base + forward, rnormal, Vector2.ZERO)
+            writer(left.first.vector3() + base + forward, lnormal, Vector2.ZERO)
+            writer(left.first.vector3() + base, lnormal, Vector2.ZERO)
+        }
+    }
+}
+
+private val Vector2.safeNormalized: Vector2
+    get() {
+
+        return if (length > 0.0001) {
+            normalized
+        } else {
+            Vector2.ZERO
+        }
+
+    }
+
+/**
+ * @suppress
+ */
+private fun sample() {
+    val shape = Circle(100.0, 100.0, 200.0).shape
+    val vbo = meshVertexBuffer(400)
+
+    val vertexCount = vbo.put {
+        extrudeShape(shape, 0.0, 10.0, 0.05, bufferWriter(this))
+    }
+}