Add isSingleComponent bool to getConstantColorComponent

src/gpu/GrProcessor.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 "GrProcessor.h"
 #include "GrBackendProcessorFactory.h"
 #include "GrContext.h"
@@ skipping 70 matching lines @@
 void GrProcessor::assertEquality(const GrProcessor& other) const {
     SkASSERT(this->numTransforms() == other.numTransforms());
     for (int i = 0; i < this->numTransforms(); ++i) {
         SkASSERT(this->coordTransform(i) == other.coordTransform(i));
     }
     SkASSERT(this->numTextures() == other.numTextures());
     for (int i = 0; i < this->numTextures(); ++i) {
         SkASSERT(this->textureAccess(i) == other.textureAccess(i));
     }
 }
+
+void GrProcessor::InvariantOutput::validate() const {
+    if (fIsSingleComponent) {
+        SkASSERT(0 == fValidFlags || kRGBA_GrColorComponentFlags == fValidFlags);
+        if (kRGBA_GrColorComponentFlags == fValidFlags) {
+            SkASSERT(this->colorComponentsAllEqual());
+        }
+    }
+
+    SkASSERT(this->validPreMulColor());
+}
+
+bool GrProcessor::InvariantOutput::colorComponentsAllEqual() const {
+    unsigned colorA = GrColorUnpackA(fColor);
+    return(GrColorUnpackR(fColor) == colorA &&
+           GrColorUnpackG(fColor) == colorA &&
+           GrColorUnpackB(fColor) == colorA);
+}
+
+bool GrProcessor::InvariantOutput::validPreMulColor() const {
+    if (kA_GrColorComponentFlag & fValidFlags) {
+        float c[4];
+        GrColorToRGBAFloat(fColor, c);
+        if (kR_GrColorComponentFlag & fValidFlags) {
+            if (c[0] > c[3]) {
+                return false;
+            }
+        }
+        if (kG_GrColorComponentFlag & fValidFlags) {
+            if (c[1] > c[3]) {
+                return false;
+            }
+        }
+        if (kB_GrColorComponentFlag & fValidFlags) {
+            if (c[2] > c[3]) {
+                return false;
+            }
+        }
+    }
+    return true;
+}
 #endif
+