Create helper functions to use in computeInvariantOutput calls

src/gpu/effects/GrDistanceFieldTextureEffect.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrDistanceFieldTextureEffect.h"
 #include "gl/builders/GrGLProgramBuilder.h"
 #include "gl/GrGLProcessor.h"
@@ skipping 189 matching lines @@
     const GrDistanceFieldTextureEffect& cte = other.cast<GrDistanceFieldTextureEffect>();
     return fTextureAccess == cte.fTextureAccess &&
 #ifdef SK_GAMMA_APPLY_TO_A8
            fGammaTextureAccess == cte.fGammaTextureAccess &&
            fLuminance == cte.fLuminance &&
 #endif
            fFlags == cte.fFlags;
 }
 
 void GrDistanceFieldTextureEffect::onComputeInvariantOutput(InvariantOutput* inout) const {
-    if (inout->isOpaque() && GrPixelConfigIsOpaque(this->texture(0)->config())) {
-        inout->fValidFlags = kA_GrColorComponentFlag;
-    } else {
-        inout->fValidFlags = 0;
-    }
-    inout->fIsSingleComponent = false;
+    inout->mulByUnknownAlpha();
 }
 
 const GrBackendGeometryProcessorFactory& GrDistanceFieldTextureEffect::getFactory() const {
     return GrTBackendGeometryProcessorFactory<GrDistanceFieldTextureEffect>::getInstance();
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 GR_DEFINE_GEOMETRY_PROCESSOR_TEST(GrDistanceFieldTextureEffect);
 
@@ skipping 158 matching lines @@
     this->addTextureAccess(&fTextureAccess);
 }
 
 bool GrDistanceFieldNoGammaTextureEffect::onIsEqual(const GrProcessor& other) const {
     const GrDistanceFieldNoGammaTextureEffect& cte = 
                                                  other.cast<GrDistanceFieldNoGammaTextureEffect>();
     return fTextureAccess == cte.fTextureAccess && fFlags == cte.fFlags;
 }
 
 void GrDistanceFieldNoGammaTextureEffect::onComputeInvariantOutput(InvariantOutput* inout) const {
-    if (inout->isOpaque() && GrPixelConfigIsOpaque(this->texture(0)->config())) {
-        inout->fValidFlags = kA_GrColorComponentFlag;
-    } else {
-        inout->fValidFlags = 0;
-    }
-    inout->fIsSingleComponent = false;
+    inout->mulByUnknownAlpha();
 }
 
 const GrBackendGeometryProcessorFactory& GrDistanceFieldNoGammaTextureEffect::getFactory() const {
     return GrTBackendGeometryProcessorFactory<GrDistanceFieldNoGammaTextureEffect>::getInstance();
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 GR_DEFINE_GEOMETRY_PROCESSOR_TEST(GrDistanceFieldNoGammaTextureEffect);
 
@@ skipping 230 matching lines @@
 
 bool GrDistanceFieldLCDTextureEffect::onIsEqual(const GrProcessor& other) const {
     const GrDistanceFieldLCDTextureEffect& cte = other.cast<GrDistanceFieldLCDTextureEffect>();
     return (fTextureAccess == cte.fTextureAccess &&
             fGammaTextureAccess == cte.fGammaTextureAccess &&
             fTextColor == cte.fTextColor &&
             fFlags == cte.fFlags);
 }
 
 void GrDistanceFieldLCDTextureEffect::onComputeInvariantOutput(InvariantOutput* inout) const {
-    if (inout->isOpaque() && GrPixelConfigIsOpaque(this->texture(0)->config())) {
-        inout->fValidFlags = kA_GrColorComponentFlag;
-    } else {
-        inout->fValidFlags = 0;
-    }
-    inout->fIsSingleComponent = false;
+    inout->mulByUnknownColor();
 }
 
 const GrBackendGeometryProcessorFactory& GrDistanceFieldLCDTextureEffect::getFactory() const {
     return GrTBackendGeometryProcessorFactory<GrDistanceFieldLCDTextureEffect>::getInstance();
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 GR_DEFINE_GEOMETRY_PROCESSOR_TEST(GrDistanceFieldLCDTextureEffect);
 
@@ skipping 23 matching lines @@
                                         random->nextULessThan(256),
                                         random->nextULessThan(256));
     uint32_t flags = kUseLCD_DistanceFieldEffectFlag;
     flags |= random->nextBool() ? kUniformScale_DistanceFieldEffectMask : 0;
     flags |= random->nextBool() ? kBGR_DistanceFieldEffectFlag : 0;
     return GrDistanceFieldLCDTextureEffect::Create(textures[texIdx], params,
                                                    textures[texIdx2], params2,
                                                    textColor,
                                                    flags);
 }