[orx-shapes] Implement RoundedRectangle using circular rounding

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

@@ -8,8 +8,19 @@ import org.openrndr.shape.ShapeContour
 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)
+    constructor(x: Double, y: Double, width: Double, height: Double, radius: Double) : this(
-    constructor(rectangle: Rectangle, radius: Double) : this(rectangle.corner, rectangle.width, rectangle.height, radius)
+        Vector2(x, y),
+        width,
+        height,
+        radius
+    )
+
+    constructor(rectangle: Rectangle, radius: Double) : this(
+        rectangle.corner,
+        rectangle.width,
+        rectangle.height,
+        radius
+    )
 
     /** the center of the rounded rectangle */
     val center: Vector2
@@ -27,16 +38,16 @@ class RoundedRectangle(val corner: Vector2, val width: Double, val height: Doubl
             moveTo(x + r, y)
             lineTo(x + width - r, y)
 
-            curveTo(Vector2(x + width, y), Vector2(x + width, y + r))
+            arcTo(r, r, 90.0, false, true, Vector2(x + width, y + r))
             lineTo(x + width, y + height - r)
 
-            curveTo(Vector2(x + width, y + height), Vector2(x + width - r, y + height))
+            arcTo(r, r, 90.0, false, true, Vector2(x + width - r, y + height))
             lineTo(x + r, y + height)
 
-            curveTo(Vector2(x, y + height), Vector2(x, y + height - r))
+            arcTo(r, r, 90.0, false, true, Vector2(x, y + height - r))
             lineTo(x, y + r)
 
-            curveTo(Vector2(x, y), Vector2(x + r, y))
+            arcTo(r, r, 90.0, false, true, Vector2(x + r, y))
             close()
         }