create struct to hold all the params passed around for shader::context

src/core/SkFilterShader.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 "SkFilterShader.h"
 
 #include "SkColorFilter.h"
@@ skipping 37 matching lines @@
     if (!(filterF & SkColorFilter::kHasFilter16_Flag)) {
         shaderF &= ~SkShader::kHasSpan16_Flag;
     }
     // if the filter might change alpha, clear the opaque flag in the shader
     if (!(filterF & SkColorFilter::kAlphaUnchanged_Flag)) {
         shaderF &= ~(SkShader::kOpaqueAlpha_Flag | SkShader::kHasSpan16_Flag);
     }
     return shaderF;
 }
 
-SkShader::Context* SkFilterShader::createContext(const SkBitmap& device,
-                                                 const SkPaint& paint,
-                                                 const SkMatrix& matrix,
-                                                 void* storage) const {
-    if (!this->validContext(device, paint, matrix)) {
+SkShader::Context* SkFilterShader::createContext(const ContextRec& rec, void* storage) const {
+    if (!this->validContext(rec, NULL)) {
         return NULL;
     }
 
     char* shaderContextStorage = (char*)storage + sizeof(FilterShaderContext);
-    SkShader::Context* shaderContext = fShader->createContext(device, paint, matrix,
-                                                              shaderContextStorage);
+    SkShader::Context* shaderContext = fShader->createContext(rec, shaderContextStorage);
     SkASSERT(shaderContext);
 
-    return SkNEW_PLACEMENT_ARGS(storage, FilterShaderContext,
-                                (*this, shaderContext, device, paint, matrix));
+    return SkNEW_PLACEMENT_ARGS(storage, FilterShaderContext, (*this, shaderContext, rec));
 }
 
 size_t SkFilterShader::contextSize() const {
     return sizeof(FilterShaderContext) + fShader->contextSize();
 }
 
-bool SkFilterShader::validContext(const SkBitmap& device,
-                                  const SkPaint& paint,
-                                  const SkMatrix& matrix,
-                                  SkMatrix* totalInverse) const {
-    return this->INHERITED::validContext(device, paint, matrix, totalInverse) &&
-           fShader->validContext(device, paint, matrix);
+bool SkFilterShader::validContext(const ContextRec& rec, SkMatrix* totalInverse) const {
+    return this->INHERITED::validContext(rec, totalInverse) && fShader->validContext(rec);
 }
 
 SkFilterShader::FilterShaderContext::FilterShaderContext(const SkFilterShader& filterShader,
                                                          SkShader::Context* shaderContext,
-                                                         const SkBitmap& device,
-                                                         const SkPaint& paint,
-                                                         const SkMatrix& matrix)
-    : INHERITED(filterShader, device, paint, matrix)
+                                                         const ContextRec& rec)
+    : INHERITED(filterShader, rec)
     , fShaderContext(shaderContext) {}
 
 SkFilterShader::FilterShaderContext::~FilterShaderContext() {
     fShaderContext->~Context();
 }
 
 void SkFilterShader::FilterShaderContext::shadeSpan(int x, int y, SkPMColor result[], int count) {
     const SkFilterShader& filterShader = static_cast<const SkFilterShader&>(fShader);
 
     fShaderContext->shadeSpan(x, y, result, count);
@@ skipping 17 matching lines @@
     str->append("Shader: ");
     fShader->toString(str);
     str->append(" Filter: ");
     // TODO: add "fFilter->toString(str);" once SkColorFilter::toString is added
 
     this->INHERITED::toString(str);
 
     str->append(")");
 }
 #endif