Add orx-shapes

orx-shapes/src/main/kotlin/RoundedRectangle.kt

@@ -0,0 +1,36 @@
+import org.openrndr.math.Vector2
+import org.openrndr.shape.contour
+import kotlin.math.min
+
+class RoundedRectangle(val corner: Vector2, val width: Double, val height: Double, val radius: Double) {
+    constructor(x: Double, y: Double, width: Double, height: Double, radius: Double) : this(Vector2(x, y), width, height, radius)
+
+    /** the center of the rounded rectangle */
+    val center: Vector2
+        get() = corner + Vector2(width / 2, height / 2)
+
+    val x: Double get() = corner.x
+    val y: Double get() = corner.y
+
+    /** [ShapeContour] representation of the rounded rectangle */
+    val contour
+        get() = contour {
+            // A higher radius than half the width/height makes it go weird
+            val r = min(min(radius, width / 2), height / 2)
+
+            moveTo(x + r, y)
+            lineTo(x + width - r, y)
+
+            curveTo(Vector2(x + width, y), Vector2(x + width, y + r))
+            lineTo(x + width, y + height - r)
+
+            curveTo(Vector2(x + width, y + height), Vector2(x + width - r, y + height))
+            lineTo(x + r, y + height)
+
+            curveTo(Vector2(x, y + height), Vector2(x, y + height - r))
+            lineTo(x, y + r)
+
+            curveTo(Vector2(x, y), Vector2(x + r, y))
+            close()
+        }
+}