[orx-shapes] Add Arc, Net, Pulley, Tear and bounds tools

orx-shapes/src/commonMain/kotlin/Tear.kt

@@ -0,0 +1,32 @@
+package org.openrndr.extra.shapes
+
+import org.openrndr.math.LinearType
+import org.openrndr.math.Polar
+import org.openrndr.math.Vector2
+import org.openrndr.shape.Circle
+import org.openrndr.shape.LineSegment
+import org.openrndr.shape.ShapeContour
+
+class Tear(val point: Vector2, val circle: Circle) : LinearType<Tear> {
+    override fun div(scale: Double) = Tear(point / scale, circle / scale)
+
+    override fun times(scale: Double) = Tear(point * scale, circle * scale)
+
+    override fun plus(right: Tear) = Tear(point + right.point, circle + right.circle)
+
+    override fun minus(right: Tear) = Tear(point - right.point, circle - right.circle)
+
+    val contour: ShapeContour
+        get() {
+            val tangents = circle.tangents(point)
+            var k = LineSegment(point, tangents.first).contour
+            run {
+                val th0 = Polar.fromVector(tangents.first - circle.center).theta
+                var th1 = Polar.fromVector(tangents.second - circle.center).theta
+                if (th1 < th0) th1 += 360.0
+                k += Arc(circle.center, circle.radius, th0, th1).contour
+            }
+            k += LineSegment(tangents.second, point).contour
+            return k.close()
+        }
+}