Create a static instances of SrcOver XferProcessor

src/gpu/glsl/GrGLSLXferProcessor.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "glsl/GrGLSLXferProcessor.h"
 
 #include "GrXferProcessor.h"
 #include "glsl/GrGLSLFragmentShaderBuilder.h"
 #include "glsl/GrGLSLProgramBuilder.h"
 #include "glsl/GrGLSLProgramDataManager.h"
 
 void GrGLSLXferProcessor::emitCode(const EmitArgs& args) {
     if (!args.fXP.willReadDstColor()) {
         this->emitOutputsForBlendState(args);
         return;
     }
 
     GrGLSLXPFragmentBuilder* fragBuilder = args.fXPFragBuilder;
     const char* dstColor = fragBuilder->dstColor();
 
     if (args.fXP.getDstTexture()) {
         bool topDown = kTopLeft_GrSurfaceOrigin == args.fXP.getDstTexture()->origin();
 
-        if (args.fXP.readsCoverage()) {
+        if (args.fInputCoverage) {
             // We don't think any shaders actually output negative coverage, but just as a safety
             // check for floating point precision errors we compare with <= here
             fragBuilder->codeAppendf("if (all(lessThanEqual(%s, vec4(0)))) {"
                                      "    discard;"
                                      "}", args.fInputCoverage);
         }
 
         const char* dstTopLeftName;
         const char* dstCoordScaleName;
 
@@ skipping 24 matching lines @@
 
     this->emitBlendCodeForDstRead(args.fPB,
                                   fragBuilder,
                                   args.fInputColor,
                                   dstColor,
                                   args.fOutputPrimary,
                                   args.fXP);
 
     // Apply coverage.
     if (args.fXP.dstReadUsesMixedSamples()) {
-        if (args.fXP.readsCoverage()) {
+        if (args.fInputCoverage) {
             fragBuilder->codeAppendf("%s *= %s;", args.fOutputPrimary, args.fInputCoverage);
             fragBuilder->codeAppendf("%s = %s;", args.fOutputSecondary, args.fInputCoverage);
         } else {
             fragBuilder->codeAppendf("%s = vec4(1.0);", args.fOutputSecondary);
         }
-    } else if (args.fXP.readsCoverage()) {
+    } else if (args.fInputCoverage) {
         fragBuilder->codeAppendf("%s = %s * %s + (vec4(1.0) - %s) * %s;",
                                  args.fOutputPrimary, args.fInputCoverage,
                                  args.fOutputPrimary, args.fInputCoverage, dstColor);
     }
 }
 
 void GrGLSLXferProcessor::setData(const GrGLSLProgramDataManager& pdm, const GrXferProcessor& xp) {
     if (xp.getDstTexture()) {
         if (fDstTopLeftUni.isValid()) {
             pdm.set2f(fDstTopLeftUni, static_cast<float>(xp.dstTextureOffset().fX),
                       static_cast<float>(xp.dstTextureOffset().fY));
             pdm.set2f(fDstScaleUni, 1.f / xp.getDstTexture()->width(),
                       1.f / xp.getDstTexture()->height());
         } else {
             SkASSERT(!fDstScaleUni.isValid());
         }
     } else {
         SkASSERT(!fDstTopLeftUni.isValid());
         SkASSERT(!fDstScaleUni.isValid());
     }
     this->onSetData(pdm, xp);
 }