缓存旋转结果

src/Nest/Path.ts

@@ -73,11 +73,15 @@ export class Path implements ISerialize
         return this;
     }
 
+    private _RotateCache = new Map<number, Path>();
     Rotate(rotation: number): Path
     {
         if (rotation === 0) return this;
+        if (this._RotateCache.has(rotation))
+            return this._RotateCache.get(rotation);
         let path = new Path();
         path.Init(this._OrigionPoints, rotation);
+        this._RotateCache.set(rotation, path);
         return path;
     }