Improve tracking of bound FBOs in GrGLGpu.

src/gpu/gl/GrGLGpu.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 GrGLGpu_DEFINED
 #define GrGLGpu_DEFINED
 
@@ skipping 32 matching lines @@
     GrGLStandard glStandard() const { return fGLContext.standard(); }
     GrGLVersion glVersion() const { return fGLContext.version(); }
     GrGLSLGeneration glslGeneration() const { return fGLContext.glslGeneration(); }
     const GrGLCaps& glCaps() const { return *fGLContext.caps(); }
 
     GrGLPathRendering* glPathRendering() {
         SkASSERT(glCaps().pathRenderingSupport());
         return static_cast<GrGLPathRendering*>(pathRendering());
     }
 
+    // On older GLs there may not be separate FBO bindings for draw and read. In that case these
+    // alias each other.
+    enum FBOBinding {
+        kDraw_FBOBinding, // drawing or dst of blit
+        kRead_FBOBinding, // src of blit, read pixels.
+    };
+
+    void willDeleteOrAbandonFramebuffer(GrGLFBO* fbo);
+
     void discard(GrRenderTarget*) SK_OVERRIDE;
 
     // Used by GrGLProgram and GrGLPathTexGenProgramEffects to configure OpenGL
     // state.
     void bindTexture(int unitIdx, const GrTextureParams& params, GrGLTexture* texture);
 
     // GrGpu overrides
     GrPixelConfig preferredReadPixelsConfig(GrPixelConfig readConfig,
                                             GrPixelConfig surfaceConfig) const SK_OVERRIDE;
     GrPixelConfig preferredWritePixelsConfig(GrPixelConfig writeConfig,
@@ skipping 176 matching lines @@
 
     void initFSAASupport();
 
     // determines valid stencil formats
     void initStencilFormats();
 
     // sets a texture unit to use for texture operations other than binding a texture to a program.
     // ensures that such operations don't negatively interact with tracking bound textures.
     void setScratchTextureUnit();
 
-    // bounds is region that may be modified and therefore has to be resolved.
-    // NULL means whole target. Can be an empty rect.
-    void flushRenderTarget(GrGLRenderTarget*, const SkIRect* bounds);
+    // Binds the render target, sets the viewport, tracks dirty are for resolve, and tracks whether
+    // mip maps need rebuilding.
+    // bounds is region that may be modified by the draw. NULL means whole target. Can be an empty
+    // rect.
+    void prepareToDrawToRenderTarget(GrGLRenderTarget*, const SkIRect* bounds);
+
+    static const FBOBinding kInvalidFBOBinding = static_cast<FBOBinding>(-1);
+
+    // binds the FBO and returns the GL enum of the framebuffer target it was bound to.
+    GrGLenum bindFBO(FBOBinding, const GrGLFBO*);
+
+    void setViewport(const GrGLIRect& viewport);
 
     void flushStencil(const GrStencilSettings&);
     void flushHWAAState(GrRenderTarget* rt, bool useHWAA, bool isLineDraw);
 
     bool configToGLFormats(GrPixelConfig config,
                            bool getSizedInternal,
                            GrGLenum* internalFormat,
                            GrGLenum* externalFormat,
                            GrGLenum* externalType);
     // helper for onCreateTexture and writeTexturePixels
@@ skipping 12 matching lines @@
     // with new data.
     bool uploadCompressedTexData(const GrSurfaceDesc& desc,
                                  const void* data,
                                  bool isNewTexture = true,
                                  int left = 0, int top = 0,
                                  int width = -1, int height = -1);
 
     bool createRenderTargetObjects(const GrSurfaceDesc&, bool budgeted, GrGLuint texID, 
                                    GrGLRenderTarget::IDDesc*);
 
-    enum TempFBOTarget {
-        kSrc_TempFBOTarget,
-        kDst_TempFBOTarget
-    };
+    // Binds a surface as an FBO. A temporary FBO ID may be used if the surface is not already
+    // a render target. Afterwards unbindSurfaceforCopy must be called with the value returned.
+    FBOBinding bindSurfaceAsFBOForCopy(GrSurface*, FBOBinding, GrGLIRect* viewport);
 
-    GrGLuint bindSurfaceAsFBO(GrSurface* surface, GrGLenum fboTarget, GrGLIRect* viewport,
-                              TempFBOTarget tempFBOTarget);
-
-    void unbindTextureFromFBO(GrGLenum fboTarget);
+    // Must be matched with bindSurfaceAsFBOForCopy.
+    void unbindSurfaceAsFBOForCopy(FBOBinding);
 
     GrGLContext fGLContext;
 
     // GL program-related state
     ProgramCache*               fProgramCache;
     SkAutoTUnref<GrGLProgram>   fCurrentProgram;
 
     ///////////////////////////////////////////////////////////////////////////
     ///@name Caching of GL State
     ///@{
     int                         fHWActiveTextureUnitIdx;
     GrGLuint                    fHWProgramID;
 
     enum TriState {
         kNo_TriState,
         kYes_TriState,
         kUnknown_TriState
     };
 
-    GrGLuint                    fTempSrcFBOID;
-    GrGLuint                    fTempDstFBOID;
-
-    GrGLuint                    fStencilClearFBOID;
+    SkAutoTUnref<GrGLFBO> fTempSrcFBO;
+    SkAutoTUnref<GrGLFBO> fTempDstFBO;
+    SkAutoTUnref<GrGLFBO> fStencilClearFBO;
 
     // last scissor / viewport scissor state seen by the GL.
     struct {
         TriState    fEnabled;
         GrGLIRect   fRect;
         void invalidate() {
             fEnabled = kUnknown_TriState;
             fRect.invalidate();
         }
     } fHWScissorSettings;
@@ skipping 125 matching lines @@
 
     TriState fMSAAEnabled;
 
     GrStencilSettings           fHWStencilSettings;
     TriState                    fHWStencilTestEnabled;
 
 
     GrPipelineBuilder::DrawFace fHWDrawFace;
     TriState                    fHWWriteToColor;
     TriState                    fHWDitherEnabled;
-    uint32_t                    fHWBoundRenderTargetUniqueID;
     SkTArray<uint32_t, true>    fHWBoundTextureUniqueIDs;
 
+    // Track read/draw fbo binding state.
+    struct HWFBOBinding {
+        uint32_t    fGenID;
+        bool        fIsDefaultFBO;
+        void invalidate() {
+            fGenID = SK_InvalidGenID;
+            fIsDefaultFBO = false;
+        }
+    } fHWFBOBinding[2];

[egdaniel, 2015/02/24 18:47:01]

Do we want to distinguish these as 0 is draw and 1 is read? Or is safe to just
use them internally as such without really forcing anything?

[bsalomon, 2015/02/24 21:00:52]

I added a cnt value and used it here. In the impl I used the enum values to
index the array.

+
     ///@}
 
     // we record what stencil format worked last time to hopefully exit early
     // from our loop that tries stencil formats and calls check fb status.
     int fLastSuccessfulStencilFmtIdx;
 
     typedef GrGpu INHERITED;
     friend class GrGLPathRendering; // For accessing setTextureUnit.
 };
 
 #endif