[orx-triangulation] Improve triangulation, add kotlin/js support

orx-triangulation/src/commonTest/kotlin/TestDelaunay.kt

@@ -0,0 +1,68 @@
+import org.openrndr.extra.triangulation.Delaunay
+import org.openrndr.math.Vector2
+import org.openrndr.shape.Circle
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertTrue
+
+class TestDelaunay {
+    /**
+     * Test if an empty triangulation can be made
+     */
+    @Test
+    fun testEmpty() {
+        val points = listOf<Vector2>()
+        val d = Delaunay.from(points)
+        assertEquals(0, d.triangles.size)
+        assertEquals(0, d.halfedges.size)
+        assertEquals(0, d.hull.size)
+        assertEquals(0, (d.neighbors(0).toList().size))
+    }
+
+    /**
+     * Test if a one point triangulation can be made
+     */
+    @Test
+    fun testOnePoint() {
+        val points = listOf(Vector2(100.0, 100.0))
+        val d = Delaunay.from(points)
+        assertEquals(0, (d.neighbors(0).toList().size))
+    }
+
+    /**
+     * Test if a two point triangulation can be made
+     */
+    @Test
+    fun testTwoPoints() {
+        val points = listOf(Vector2(100.0, 100.0), Vector2(300.0, 100.0))
+        val d = Delaunay.from(points)
+        println(d.triangles.size)
+        println("${d.triangles[0]}, ${d.triangles[1]}, ${d.triangles[2]}")
+
+        // this will be one degenerate triangle since we only have 2 points
+        assertEquals(3, d.triangles.size)
+        assertEquals(2, d.hull.size)
+
+        assertEquals(1, (d.neighbors(0).toList().size))
+        assertEquals(1, (d.neighbors(0).toList().first()))
+
+        assertEquals(1, (d.neighbors(1).toList().size))
+        assertEquals(0, (d.neighbors(1).toList().first()))
+    }
+
+    @Test
+    fun testThreePointsCollinear() {
+        val points = listOf(Vector2(100.0, 100.0), Vector2(200.0, 100.0), Vector2(300.0, 100.0))
+        val d = Delaunay.from(points)
+        assertEquals(3, d.triangles.size)
+    }
+
+    @Test
+    fun testNeighbors() {
+        val c = Circle(200.0, 200.0, 150.0).contour.equidistantPositions(20).take(20)
+        val d = Delaunay.from(c)
+        for (j in c.indices) {
+            assertTrue(d.neighbors(j).toList().isNotEmpty())
+        }
+    }
+}