Revert of Add a class representing texture swizzle.

src/gpu/GrTextureAccess.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 "GrTextureAccess.h"
 #include "GrColor.h"
 #include "GrTexture.h"
 
-GrTextureAccess::GrTextureAccess() {}
+GrTextureAccess::GrTextureAccess() {
+#ifdef SK_DEBUG
+    memcpy(fSwizzle, "void", 5);
+    fSwizzleMask = 0xbeeffeed;
+#endif
+}
 
 GrTextureAccess::GrTextureAccess(GrTexture* texture, const GrTextureParams& params) {
     this->reset(texture, params);
 }
 
 GrTextureAccess::GrTextureAccess(GrTexture* texture,
                                  GrTextureParams::FilterMode filterMode,
                                  SkShader::TileMode tileXAndY) {
     this->reset(texture, filterMode, tileXAndY);
 }
 
+GrTextureAccess::GrTextureAccess(GrTexture* texture,
+                                 const char* swizzle,
+                                 const GrTextureParams& params) {
+    this->reset(texture, swizzle, params);
+}
+
+GrTextureAccess::GrTextureAccess(GrTexture* texture,
+                                 const char* swizzle,
+                                 GrTextureParams::FilterMode filterMode,
+                                 SkShader::TileMode tileXAndY) {
+    this->reset(texture, swizzle, filterMode, tileXAndY);
+}
+
+void GrTextureAccess::reset(GrTexture* texture,
+                            const char* swizzle,
+                            const GrTextureParams& params) {
+    SkASSERT(texture);
+    SkASSERT(strlen(swizzle) >= 1 && strlen(swizzle) <= 4);
+
+    fParams = params;
+    fTexture.set(SkRef(texture), kRead_GrIOType);
+    this->setSwizzle(swizzle);
+}
+
+void GrTextureAccess::reset(GrTexture* texture,
+                            const char* swizzle,
+                            GrTextureParams::FilterMode filterMode,
+                            SkShader::TileMode tileXAndY) {
+    SkASSERT(texture);
+    SkASSERT(strlen(swizzle) >= 1 && strlen(swizzle) <= 4);
+
+    fParams.reset(tileXAndY, filterMode);
+    fTexture.set(SkRef(texture), kRead_GrIOType);
+    this->setSwizzle(swizzle);
+}
 
 void GrTextureAccess::reset(GrTexture* texture,
                             const GrTextureParams& params) {
     SkASSERT(texture);
     fTexture.set(SkRef(texture), kRead_GrIOType);
     fParams = params;
+    memcpy(fSwizzle, "rgba", 5);
+    fSwizzleMask = kRGBA_GrColorComponentFlags;
 }
 
 void GrTextureAccess::reset(GrTexture* texture,
                             GrTextureParams::FilterMode filterMode,
                             SkShader::TileMode tileXAndY) {
     SkASSERT(texture);
     fTexture.set(SkRef(texture), kRead_GrIOType);
     fParams.reset(tileXAndY, filterMode);
+    memcpy(fSwizzle, "rgba", 5);
+    fSwizzleMask = kRGBA_GrColorComponentFlags;
 }
+
+void GrTextureAccess::setSwizzle(const char* swizzle) {
+    fSwizzleMask = 0;
+    memset(fSwizzle, '\0', 5);
+    for (int i = 0; i < 4 && '\0' != swizzle[i]; ++i) {
+        fSwizzle[i] = swizzle[i];
+        switch (swizzle[i]) {
+            case 'r':
+                fSwizzleMask |= kR_GrColorComponentFlag;
+                break;
+            case 'g':
+                fSwizzleMask |= kG_GrColorComponentFlag;
+                break;
+            case 'b':
+                fSwizzleMask |= kB_GrColorComponentFlag;
+                break;
+            case 'a':
+                fSwizzleMask |= kA_GrColorComponentFlag;
+                break;
+            default:
+                SkFAIL("Unexpected swizzle string character.");
+                break;
+        }
+    }
+}