Add XferProcessor factory in GrPaint and GrDrawState.

src/gpu/GrDrawState.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 GrDrawState_DEFINED
 #define GrDrawState_DEFINED
 
@@ skipping 197 matching lines @@
      * initial value (after construction or reset()) is 0xff. The constant
      * coverage is ignored when per-vertex coverage is provided.
      */
     void setCoverage(uint8_t coverage) {
         if (coverage != fCoverage) {
             fCoverage = coverage;
             fCoverageProcInfoValid = false;
         }
     }
 
+    /**
+     * Determines whether the output of the coverage stages will be single component.
+     */
+    bool coverageWillBeSingleComponent() const;

[bsalomon, 2014/11/26 21:02:45]

needs to be public?

[egdaniel, 2014/12/01 18:18:24]

It is a query used by PD-XPF for checking RGBCoverage. Currently we hide DS's
invariant output from all classes except GrOptDrawState. I don't want to open
the flood gate to friending all effects.

I guess the change we can make is to have this function (and in future cl's
createXferProcessor(...)) take in the invariant color and coverage instead of
the draw state. But this does mess with the query's in the text context for
applyRGBCoverage since they won't have access to the DS invariants to pass in.

I kind of feel in the end public queries on the DS end up being clearer and
cleaner.

[bsalomon, 2014/12/01 19:24:39]

I don't think PD-XPF should be allowed to see GrDrawState at all. It's private.
I think we need some encapsulation of just the info that XP(F) is allowed to
see.

+
     /// @}
 
     /**
      * The geometry processor is the sole element of the skia pipeline which can use the vertex,
      * geometry, and tesselation shaders.  The GP may also compute a coverage in its fragment shader
      * but is never put in the color processing pipeline.
      */
 
     const GrGeometryProcessor* setGeometryProcessor(const GrGeometryProcessor* geometryProcessor) {
         SkASSERT(geometryProcessor);
@@ skipping 25 matching lines @@
 
     int numColorStages() const { return fColorStages.count(); }
     int numCoverageStages() const { return fCoverageStages.count(); }
     int numFragmentStages() const { return this->numColorStages() + this->numCoverageStages(); }
     int numTotalStages() const {
          return this->numFragmentStages() + (this->hasGeometryProcessor() ? 1 : 0);
     }
 
     bool hasGeometryProcessor() const { return SkToBool(fGeometryProcessor.get()); }
     const GrGeometryProcessor* getGeometryProcessor() const { return fGeometryProcessor.get(); }
+
+    bool hasXPFactory() const { return SkToBool(fXPFactory.get()); }
+    const GrXPFactory* getXPFactory() const { return fXPFactory.get(); }
+
     const GrFragmentStage& getColorStage(int idx) const { return fColorStages[idx]; }
     const GrFragmentStage& getCoverageStage(int idx) const { return fCoverageStages[idx]; }
 
     /**
      * Checks whether any of the effects will read the dst pixel color.
      */
     bool willEffectReadDstColor() const;
 
     const GrFragmentProcessor* addColorProcessor(const GrFragmentProcessor* effect) {
         SkASSERT(effect);
@@ skipping 503 matching lines @@
     uint32_t                                fFlagBits;
     const GrVertexAttrib*                   fVAPtr;
     int                                     fVACount;
     size_t                                  fVAStride;
     GrStencilSettings                       fStencilSettings;
     uint8_t                                 fCoverage;
     DrawFace                                fDrawFace;
     GrBlendCoeff                            fSrcBlend;
     GrBlendCoeff                            fDstBlend;
     SkAutoTUnref<const GrGeometryProcessor> fGeometryProcessor;
+    SkAutoTUnref<const GrXPFactory>         fXPFactory;
     FragmentStageArray                      fColorStages;
     FragmentStageArray                      fCoverageStages;
     uint32_t                                fHints;
 
     // This is simply a different representation of info in fVertexAttribs and thus does
     // not need to be compared in op==.
     int fFixedFunctionVertexAttribIndices[kGrFixedFunctionVertexAttribBindingCnt];
 
     mutable GrProcOptInfo fColorProcInfo;
     mutable GrProcOptInfo fCoverageProcInfo;
     mutable bool fColorProcInfoValid;
     mutable bool fCoverageProcInfoValid;
 
     friend class GrOptDrawState;
 };
 
 #endif