Potentially optimize some GrGLEffects for known input color values

src/gpu/effects/GrConvolutionEffect.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrConvolutionEffect.h"
 #include "gl/GrGLEffect.h"
 #include "gl/GrGLSL.h"
 #include "gl/GrGLTexture.h"
 #include "GrTBackendEffectFactory.h"
 
 // For brevity
 typedef GrGLUniformManager::UniformHandle UniformHandle;
 
 class GrGLConvolutionEffect : public GrGLEffect {
 public:
     GrGLConvolutionEffect(const GrBackendEffectFactory&, const GrDrawEffect&);
 
     virtual void emitCode(GrGLShaderBuilder*,
                           const GrDrawEffect&,
                           EffectKey,
                           const char* outputColor,
-                          const char* inputColor,
+                          const GrGLSLExpr4& inputColor,
                           const TransformedCoordsArray&,
                           const TextureSamplerArray&) SK_OVERRIDE;
 
     virtual void setData(const GrGLUniformManager& uman, const GrDrawEffect&) SK_OVERRIDE;
 
     static inline EffectKey GenKey(const GrDrawEffect&, const GrGLCaps&);
 
 private:
     int width() const { return Gr1DKernelEffect::WidthFromRadius(fRadius); }
     bool useBounds() const { return fUseBounds; }
@@ skipping 15 matching lines @@
     const GrConvolutionEffect& c = drawEffect.castEffect<GrConvolutionEffect>();
     fRadius = c.radius();
     fUseBounds = c.useBounds();
     fDirection = c.direction();
 }
 
 void GrGLConvolutionEffect::emitCode(GrGLShaderBuilder* builder,
                                      const GrDrawEffect&,
                                      EffectKey key,
                                      const char* outputColor,
-                                     const char* inputColor,
+                                     const GrGLSLExpr4& inputColor,
                                      const TransformedCoordsArray& coords,
                                      const TextureSamplerArray& samplers) {
     SkString coords2D = builder->ensureFSCoords2D(coords, 0);
     fImageIncrementUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
                                              kVec2f_GrSLType, "ImageIncrement");
     if (this->useBounds()) {
         fBoundsUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
                                          kVec2f_GrSLType, "Bounds");
     }
     fKernelUni = builder->addUniformArray(GrGLShaderBuilder::kFragment_Visibility,
@@ skipping 157 matching lines @@
     }
 
     bool useBounds = random->nextBool();
     return GrConvolutionEffect::Create(textures[texIdx],
                                        dir,
                                        radius,
                                        kernel,
                                        useBounds,
                                        bounds);
 }