Create a static instances of SrcOver XferProcessor

src/gpu/GrPipeline.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrPipeline_DEFINED
 #define GrPipeline_DEFINED
 
@@ skipping 123 matching lines @@
      * Gets whether the target is drawing clockwise, counterclockwise,
      * or both faces.
      * @return the current draw face(s).
      */
     GrPipelineBuilder::DrawFace getDrawFace() const { return fDrawFace; }
 
 
     ///////////////////////////////////////////////////////////////////////////
 
     bool readsFragPosition() const { return fReadsFragPosition; }
+    bool readsCoverage() const { return fReadsCoverage; }
 
 private:
     GrPipeline() { /** Initialized in factory function*/ }
 
     /**
      * Alter the program desc and inputs (attribs and processors) based on the blend optimization.
      */
     void adjustProgramFromOptimizations(const GrPipelineBuilder& ds,
                                         GrXferProcessor::OptFlags,
                                         const GrProcOptInfo& colorPOI,
@@ skipping 19 matching lines @@
     typedef SkAutoSTArray<8, PendingFragmentProcessor> FragmentProcessorArray;
     typedef GrPendingProgramElement<const GrXferProcessor> ProgramXferProcessor;
     RenderTarget                        fRenderTarget;
     GrScissorState                      fScissorState;
     GrStencilSettings                   fStencilSettings;
     GrPipelineBuilder::DrawFace         fDrawFace;
     uint32_t                            fFlags;
     ProgramXferProcessor                fXferProcessor;
     FragmentProcessorArray              fFragmentProcessors;
     bool                                fReadsFragPosition;
+    bool                                fReadsCoverage; // Will this program use coverage?

[bsalomon, 2015/11/30 15:56:53]

Given that this is now moved from XP to Pipeline, maybe it should a new name
that is more explicit? fXPUsesCoverage? 

[egdaniel, 2015/11/30 16:29:14]

Done.

 
     // This value is also the index in fFragmentProcessors where coverage processors begin.
     int                                 fNumColorProcessors;
 
     typedef SkRefCnt INHERITED;
 };
 
 #endif