Expand modulate, add, subtract, extract component glsl helpers.

include/gpu/GrTypesPriv.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrTypesPriv_DEFINED
 #define GrTypesPriv_DEFINED
 
@@ skipping 30 matching lines @@
     GR_STATIC_ASSERT(1 == kFloat_GrSLType);
     GR_STATIC_ASSERT(2 == kVec2f_GrSLType);
     GR_STATIC_ASSERT(3 == kVec3f_GrSLType);
     GR_STATIC_ASSERT(4 == kVec4f_GrSLType);
     GR_STATIC_ASSERT(5 == kMat33f_GrSLType);
     GR_STATIC_ASSERT(6 == kMat44f_GrSLType);
     GR_STATIC_ASSERT(7 == kSampler2D_GrSLType);
     GR_STATIC_ASSERT(GR_ARRAY_COUNT(kCounts) == kGrSLTypeCount);
 }
 
+/** Return the type enum for a vector of floats of length n (1..4),
+ e.g. 1 -> kFloat_GrSLType, 2 -> kVec2_GrSLType, ... */
 static inline GrSLType GrSLFloatVectorType(int count) {
     GrAssert(count > 0 && count <= 4);
     return (GrSLType)(count);
 
     GR_STATIC_ASSERT(kFloat_GrSLType == 1);
     GR_STATIC_ASSERT(kVec2f_GrSLType == 2);
     GR_STATIC_ASSERT(kVec3f_GrSLType == 3);
     GR_STATIC_ASSERT(kVec4f_GrSLType == 4);
 }
 
@@ skipping 97 matching lines @@
     bool operator!=(const GrVertexAttrib& other) const { return !(*this == other); }
 
     GrVertexAttribType      fType;
     size_t                  fOffset;
     GrVertexAttribBinding   fBinding;
 };
 
 template <int N> class GrVertexAttribArray : public SkSTArray<N, GrVertexAttrib, true> {};
 
 #endif