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

src/core/SkShader.cpp

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmapProcShader.h"
 #include "SkReadBuffer.h"
 #include "SkMallocPixelRef.h"
@@ skipping 38 matching lines @@
     SkMatrix        total;
 
     if (this->hasLocalMatrix()) {
         total.setConcat(matrix, this->getLocalMatrix());
         m = &total;
     }
 
     return m->invert(totalInverse);
 }
 
-bool SkShader::validContext(const SkBitmap& device,
-                            const SkPaint& paint,
-                            const SkMatrix& matrix,
-                            SkMatrix* totalInverse) const {
-    return this->computeTotalInverse(matrix, totalInverse);
+bool SkShader::validContext(const ContextRec& rec, SkMatrix* totalInverse) const {
+    return this->computeTotalInverse(*rec.fMatrix, totalInverse);
 }
 
-SkShader::Context* SkShader::createContext(const SkBitmap&, const SkPaint&, const SkMatrix&,
-                                           void* storage) const {
+SkShader::Context* SkShader::createContext(const ContextRec&, void* storage) const {
     return NULL;
 }
 
 size_t SkShader::contextSize() const {
     return 0;
 }
 
-SkShader::Context::Context(const SkShader& shader, const SkBitmap& device,
-                           const SkPaint& paint, const SkMatrix& matrix)
+SkShader::Context::Context(const SkShader& shader, const ContextRec& rec)
     : fShader(shader)
 {
-    SkASSERT(fShader.validContext(device, paint, matrix));
+    SkASSERT(fShader.validContext(rec));
 
     // Because the context parameters must be valid at this point, we know that the matrix is
     // invertible.
-    SkAssertResult(fShader.computeTotalInverse(matrix, &fTotalInverse));
+    SkAssertResult(fShader.computeTotalInverse(*rec.fMatrix, &fTotalInverse));
     fTotalInverseClass = (uint8_t)ComputeMatrixClass(fTotalInverse);
 
-    fPaintAlpha = paint.getAlpha();
+    fPaintAlpha = rec.fPaint->getAlpha();
 }
 
 SkShader::Context::~Context() {}
 
 SkShader::Context::ShadeProc SkShader::Context::asAShadeProc(void** ctx) {
     return NULL;
 }
 
 #include "SkColorPriv.h"
 
@@ skipping 146 matching lines @@
 }
 
 uint32_t SkColorShader::ColorShaderContext::getFlags() const {
     return fFlags;
 }
 
 uint8_t SkColorShader::ColorShaderContext::getSpan16Alpha() const {
     return SkGetPackedA32(fPMColor);
 }
 
-SkShader::Context* SkColorShader::createContext(const SkBitmap& device, const SkPaint& paint,
-                                                const SkMatrix& matrix, void* storage) const {
-    if (!this->validContext(device, paint, matrix)) {
+SkShader::Context* SkColorShader::createContext(const ContextRec& rec, void* storage) const {
+    if (!this->validContext(rec)) {
         return NULL;
     }
 
-    return SkNEW_PLACEMENT_ARGS(storage, ColorShaderContext, (*this, device, paint, matrix));
+    return SkNEW_PLACEMENT_ARGS(storage, ColorShaderContext, (*this, rec));
 }
 
 SkColorShader::ColorShaderContext::ColorShaderContext(const SkColorShader& shader,
-                                                      const SkBitmap& device,
-                                                      const SkPaint& paint,
-                                                      const SkMatrix& matrix)
-    : INHERITED(shader, device, paint, matrix)
+                                                      const ContextRec& rec)
+    : INHERITED(shader, rec)
 {
     SkColor color = shader.fColor;
-    unsigned a = SkAlphaMul(SkColorGetA(color), SkAlpha255To256(paint.getAlpha()));
+    unsigned a = SkAlphaMul(SkColorGetA(color), SkAlpha255To256(rec.fPaint->getAlpha()));
 
     unsigned r = SkColorGetR(color);
     unsigned g = SkColorGetG(color);
     unsigned b = SkColorGetB(color);
 
     // we want this before we apply any alpha
     fColor16 = SkPack888ToRGB16(r, g, b);
 
     if (a != 255) {
         r = SkMulDiv255Round(r, a);
         g = SkMulDiv255Round(g, a);
         b = SkMulDiv255Round(b, a);
     }
     fPMColor = SkPackARGB32(a, r, g, b);
 
     fFlags = kConstInY32_Flag;
     if (255 == a) {
         fFlags |= kOpaqueAlpha_Flag;
-        if (paint.isDither() == false) {
+        if (rec.fPaint->isDither() == false) {
             fFlags |= kHasSpan16_Flag;
         }
     }
 }
 
 void SkColorShader::ColorShaderContext::shadeSpan(int x, int y, SkPMColor span[], int count) {
     sk_memset32(span, fPMColor, count);
 }
 
 void SkColorShader::ColorShaderContext::shadeSpan16(int x, int y, uint16_t span[], int count) {
@@ skipping 40 matching lines @@
 #include "SkEmptyShader.h"
 
 void SkEmptyShader::toString(SkString* str) const {
     str->append("SkEmptyShader: (");
 
     this->INHERITED::toString(str);
 
     str->append(")");
 }
 #endif