Merge pull request #1842 from hightopo/fix-mask-filter-bug

Fix mask combine filter bug

src/pixi/renderers/webgl/utils/WebGLFilterManager.js

@@ -73,7 +73,14 @@ PIXI.WebGLFilterManager.prototype.pushFilter = function(filterBlock)
     var offset = this.renderSession.offset;
 
     filterBlock._filterArea = filterBlock.target.filterArea || filterBlock.target.getBounds();
-
+
+    // >>> modify by nextht
+    filterBlock._previous_stencil_mgr = this.renderSession.stencilManager;
+    this.renderSession.stencilManager = new PIXI.WebGLStencilManager();
+    this.renderSession.stencilManager.setContext(gl);
+    gl.disable(gl.STENCIL_TEST);
+    // <<<  modify by nextht 
+
     // filter program
     // OPTIMISATION - the first filter is free if its a simple color change?
     this.filterStack.push(filterBlock);
@@ -298,6 +305,20 @@ PIXI.WebGLFilterManager.prototype.popFilter = function()
     gl.activeTexture(gl.TEXTURE0);
     gl.bindTexture(gl.TEXTURE_2D, texture.texture);
 
+    // >>> modify by nextht
+    if (this.renderSession.stencilManager) {
+        this.renderSession.stencilManager.destroy();
+    }
+    this.renderSession.stencilManager = filterBlock._previous_stencil_mgr;
+    filterBlock._previous_stencil_mgr = null;
+    if (this.renderSession.stencilManager.count > 0) {
+        gl.enable(gl.STENCIL_TEST);
+    }
+    else {
+        gl.disable(gl.STENCIL_TEST);
+    }    
+    // <<< modify by nextht
+
     // apply!
     this.applyFilterPass(filter, filterArea, sizeX, sizeY);