Remove GrTexture::releaseRenderTarget() and add GrSurface::isSameAs().

include/gpu/GrTexture.h

 
 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrTexture_DEFINED
 #define GrTexture_DEFINED
 
 #include "GrSurface.h"
 #include "SkPoint.h"
+#include "GrRenderTarget.h"
 
-class GrRenderTarget;
 class GrResourceKey;
 class GrTextureParams;
 
 class GrTexture : public GrSurface {
 
 public:
     SK_DECLARE_INST_COUNT(GrTexture)
     // from GrResource
     /**
      * Informational texture flags
@@ skipping 47 matching lines @@
     virtual const GrTexture* asTexture() const SK_OVERRIDE { return this; }
 
     /**
      * Retrieves the render target underlying this texture that can be passed to
      * GrGpu::setRenderTarget().
      *
      * @return    handle to render target or NULL if the texture is not a
      *            render target
      */
     virtual GrRenderTarget* asRenderTarget() SK_OVERRIDE {
-        return fRenderTarget;
+        return fRenderTarget.get();
     }
     virtual const GrRenderTarget* asRenderTarget() const SK_OVERRIDE {
-        return fRenderTarget;
+        return fRenderTarget.get();
     }
 
     // GrTexture
     /**
      * Convert from texels to normalized texture coords for POT textures
      * only.
      */
     GrFixed normalizeFixedX(GrFixed x) const {
         GrAssert(GrIsPow2(fDesc.fWidth));
         return x >> fShiftFixedX;
     }
     GrFixed normalizeFixedY(GrFixed y) const {
         GrAssert(GrIsPow2(fDesc.fHeight));
         return y >> fShiftFixedY;
     }
 
     /**
-     * Removes the reference on the associated GrRenderTarget held by this
-     * texture. Afterwards asRenderTarget() will return NULL. The
-     * GrRenderTarget survives the release if another ref is held on it.
-     */
-    void releaseRenderTarget();
-
-    /**
      *  Return the native ID or handle to the texture, depending on the
      *  platform. e.g. on OpenGL, return the texture ID.
      */
     virtual GrBackendObject getTextureHandle() const = 0;
 
     /**
      *  Call this when the state of the native API texture object is
      *  altered directly, without being tracked by skia.
      */
     virtual void invalidateCachedState() = 0;
 
 #if GR_DEBUG
     void validate() const {
         this->INHERITED::validate();
 
         this->validateDesc();
     }
 #else
     void validate() const {}
 #endif
     static GrResourceKey ComputeKey(const GrGpu* gpu,
                                     const GrTextureParams* params,
                                     const GrTextureDesc& desc,
                                     const GrCacheID& cacheID);
     static GrResourceKey ComputeScratchKey(const GrTextureDesc& desc);
     static bool NeedsResizing(const GrResourceKey& key);
     static bool NeedsFiltering(const GrResourceKey& key);
 
 protected:
-    GrRenderTarget* fRenderTarget; // texture refs its rt representation
-                                   // base class cons sets to NULL
-                                   // subclass cons can create and set
+    // A texture refs its rt representation but not vice-versa. It is up to
+    // the subclass constructor to initialize this pointer.
+    SkAutoTUnref<GrRenderTarget> fRenderTarget;
 
     GrTexture(GrGpu* gpu, bool isWrapped, const GrTextureDesc& desc)
     : INHERITED(gpu, isWrapped, desc)
     , fRenderTarget(NULL) {
 
         // only make sense if alloc size is pow2
         fShiftFixedX = 31 - SkCLZ(fDesc.fWidth);
         fShiftFixedY = 31 - SkCLZ(fDesc.fHeight);
     }
 
@@ skipping 46 matching lines @@
     GrTexture* setTexture(GrTexture* texture) {
         fTexture.reset(SkSafeRef(texture));
         return texture;
     }
 private:
     SkAutoTUnref<GrTexture> fTexture;
     SkIPoint                fOffset;
 };
 
 #endif