Implement support for mixed sampled render targets

src/gpu/GrPipeline.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrPipeline.h"
 
 #include "GrBatch.h"
@@ skipping 15 matching lines @@
 
     GrColor overrideColor = GrColor_ILLEGAL;
     if (colorPOI.firstEffectiveStageIndex() != 0) {
         overrideColor = colorPOI.inputColorToEffectiveStage();
     }
 
     GrXferProcessor::OptFlags optFlags;
     if (xferProcessor) {
         fXferProcessor.reset(xferProcessor.get());
 
-        optFlags = xferProcessor->getOptimizations(colorPOI,
+        GrProcOptInfo localColorPOI = colorPOI;
+        // Optimizations will try to turn off blending which is required by mixed
+        // sampled modes.
+        SkASSERT(pipelineBuilder.fRenderTarget.get());
+        bool isMixedSampledTarget = pipelineBuilder.fRenderTarget.get()->sampleConfig() ==
+                                    GrRenderTarget::kStencil_SampleConfig;
+        localColorPOI.setHasMixedSamplesModulation(pipelineBuilder.isHWAntialias() &&
+                                                   isMixedSampledTarget);
+
+        optFlags = xferProcessor->getOptimizations(localColorPOI,
                                                    coveragePOI,
                                                    pipelineBuilder.getStencil().doesWrite(),
                                                    &overrideColor,
                                                    caps);
     }
 
     // When path rendering the stencil settings are not always set on the GrPipelineBuilder
     // so we must check the draw type. In cases where we will skip drawing we simply return a
     // null GrPipeline.
     if (!xferProcessor || (GrXferProcessor::kSkipDraw_OptFlag & optFlags)) {
@@ skipping 106 matching lines @@
     SkASSERT(this->numFragmentStages() == that.numFragmentStages());
     for (int i = 0; i < this->numFragmentStages(); i++) {
 
         if (this->getFragmentStage(i) != that.getFragmentStage(i)) {
             return false;
         }
     }
     return true;
 }