Dynamically create stencil buffer when needed.

src/gpu/GrRenderTarget.cpp

 
 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "GrRenderTarget.h"
 
 #include "GrContext.h"
 #include "GrGpu.h"
+#include "GrRenderTargetPriv.h"
 #include "GrStencilBuffer.h"
 
 void GrRenderTarget::discard() {
     // go through context so that all necessary flushing occurs
     GrContext* context = this->getContext();
     if (NULL == context) {
         return;
     }
     context->discardRenderTarget(this);
 }
@@ skipping 15 matching lines @@
     fResolveRect = rect;
     if (fResolveRect.isEmpty()) {
         fResolveRect.setLargestInverted();
     } else {
         if (!fResolveRect.intersect(0, 0, this->width(), this->height())) {
             fResolveRect.setLargestInverted();
         }
     }
 }
 
-void GrRenderTarget::setStencilBuffer(GrStencilBuffer* stencilBuffer) {
-    SkRefCnt_SafeAssign(fStencilBuffer, stencilBuffer);
-}
-
 void GrRenderTarget::onRelease() {
-    this->setStencilBuffer(NULL);
+    this->renderTargetPriv().didAttachStencilBuffer(NULL);
 
     INHERITED::onRelease();
 }
 
 void GrRenderTarget::onAbandon() {
-    this->setStencilBuffer(NULL);
+    this->renderTargetPriv().didAttachStencilBuffer(NULL);
 
     INHERITED::onAbandon();
 }
+
+///////////////////////////////////////////////////////////////////////////////
+
+void GrRenderTargetPriv::didAttachStencilBuffer(GrStencilBuffer* stencilBuffer) {
+    SkRefCnt_SafeAssign(fRenderTarget->fStencilBuffer, stencilBuffer);
+}
+
+GrStencilBuffer* GrRenderTargetPriv::attachStencilBuffer() const {
+    if (fRenderTarget->fStencilBuffer) {
+        return fRenderTarget->fStencilBuffer;
+    }
+    if (!fRenderTarget->wasDestroyed() && fRenderTarget->canAttemptStencilAttachment()) {
+        fRenderTarget->getGpu()->attachStencilBufferToRenderTarget(fRenderTarget);
+    }
+    return fRenderTarget->fStencilBuffer;
+}