新增Phyisics.overlapRectangle

新增TextureUtils.premultiplyAlpha
新增Entity快速访问Transform内联方法

source/src/Utils/Extensions/TextureUtils.ts

@@ -0,0 +1,15 @@
+module es {
+    export class TextureUtils {
+        public static premultiplyAlpha(pixels: number[]) {
+            let b = pixels[0];
+            for (let i = 0; i < pixels.length; i += 4) {
+                if (b[i + 3] != 255) {
+                    let alpha = b[i + 3] / 255;
+                    b[i + 0] = b[i + 0] * alpha;
+                    b[i + 1] = b[i + 1] * alpha;
+                    b[i + 2] = b[i + 2] * alpha;
+                }
+            }
+        }
+    }
+}