Improve needDraw logic

Author: pandamicro

cocos2d/core/sprites/CCSpriteWebGLRenderCmd.js

@@ -523,8 +523,7 @@
     };
 
     proto.needDraw = function () {
-        var node = this._node, locTexture = node._texture;
-        return (this._buffer && locTexture && locTexture._textureLoaded && node._rect.width && node._rect.height && this._displayedOpacity);
+        return (this._buffer && this._node._texture);
     };
 
     proto.rendering = function (ctx) {

cocos2d/render-texture/CCRenderTextureWebGLRenderCmd.js

@@ -48,6 +48,10 @@
         this._fullViewport = fullViewport;
     };
 
+    proto.needDraw = function () {
+        return this._needDraw && this._node.autoDraw;
+    };
+
     proto.rendering = function (ctx) {
         var gl = ctx || cc._renderContext;
         var node = this._node;