Initial commit

Library/PackageCache/com.unity.2d.path@2.1.0/Editor/Shapes/ShapeExtensions.cs

@@ -0,0 +1,102 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+namespace UnityEditor.U2D.Path
+{
+    public static class ShapeExtensions
+    {
+        public static Polygon ToPolygon(this Vector3[] points, bool isOpenEnded)
+        {
+           return new Polygon()
+           {
+               isOpenEnded = isOpenEnded,
+               points = points
+            };
+        }
+
+        public static Spline ToSpline(this Vector3[] points, bool isOpenEnded)
+        {
+            if (!points.IsSpline(isOpenEnded) && points.IsSpline(!isOpenEnded))
+            {
+                var pointList = new List<Vector3>(points);
+
+                if (isOpenEnded)
+                {
+                    while (pointList.Count % 3 != 1)
+                        pointList.RemoveAt(pointList.Count-1);
+
+                    points = pointList.ToArray();
+                }
+                else
+                {
+                    var last = pointList[pointList.Count-1];
+                    var first = pointList[0];
+                    var v = first - last;
+
+                    pointList.Add(last + v.normalized * (v.magnitude / 3f));
+                    pointList.Add(first - v.normalized * (v.magnitude / 3f));
+
+                    points = pointList.ToArray();
+                }
+            }
+            
+            if (!points.IsSpline(isOpenEnded))
+                throw new Exception("The provided control point array can't conform a Spline.");
+
+            return new Spline()
+            {
+                isOpenEnded = isOpenEnded,
+                points = points
+            };
+        }
+
+        public static bool IsSpline(this Vector3[] points, bool isOpenEnded)
+        {
+            if (points.Length < 4)
+                return false;
+
+            if (isOpenEnded && points.Length % 3 != 1)
+                return false;
+
+            if (!isOpenEnded && points.Length % 3 != 0)
+                return false;
+
+            return true;
+        }
+
+        public static Spline ToSpline(this Polygon polygon)
+        {
+            var newPointCount = polygon.points.Length * 3;
+
+            if (polygon.isOpenEnded)
+                newPointCount = (polygon.points.Length - 1) * 3 + 1;
+
+            var newPoints = new Vector3[newPointCount];
+            var controlPoints = polygon.points;
+            var pointCount = controlPoints.Length;
+
+            for (var i = 0; i < pointCount; ++i)
+            {
+                var nextIndex = (i + 1) % pointCount;
+                var point = controlPoints[i];
+                var v = controlPoints[nextIndex] - point;
+
+                newPoints[i * 3] = point;
+
+                if (i * 3 + 2 < newPointCount)
+                {
+                    newPoints[i * 3 + 1] = point + v / 3f;
+                    newPoints[i * 3 + 2] = point + v * 2f / 3f;
+                }
+            }
+
+            return new Spline()
+            {
+                isOpenEnded = polygon.isOpenEnded,
+                points = newPoints
+            };
+        }
+    }
+}