Make GrGLShaderBuilder::TextureSampler extract only required info from GrTextureAccess.

This will make it possible to init a TextureSampler without a texture or a specific config.

Also unify two separate bitfields of color components in GPU code.
Review URL: https://codereview.chromium.org/13121002

git-svn-id: http://skia.googlecode.com/svn/trunk@8428 2bbb7eff-a529-9590-31e7-b0007b416f81

4 files changed, 42 insertions, 34 deletions

diff --git a/src/gpu/gl/GrGLCaps.cpp b/src/gpu/gl/GrGLCaps.cpp
index 5e555f9653..1f3cf16464 100644
--- a/src/gpu/gl/GrGLCaps.cpp
+++ b/src/gpu/gl/GrGLCaps.cpp
@@ -462,7 +462,7 @@ void GrGLCaps::markColorConfigAndStencilFormatAsVerified(
 #if !GR_GL_CHECK_FBO_STATUS_ONCE_PER_FORMAT
     return;
 #endif
-    GrAssert((unsigned)config < kGrPixelConfigCount);
+    GrAssert((unsigned)config < kGrPixelConfigCnt);
     GrAssert(fStencilFormats.count() == fStencilVerifiedColorConfigs.count());
     int count = fStencilFormats.count();
     // we expect a really small number of possible formats so linear search
@@ -485,7 +485,7 @@ bool GrGLCaps::isColorConfigAndStencilFormatVerified(
 #if !GR_GL_CHECK_FBO_STATUS_ONCE_PER_FORMAT
     return false;
 #endif
-    GrAssert((unsigned)config < kGrPixelConfigCount);
+    GrAssert((unsigned)config < kGrPixelConfigCnt);
     int count = fStencilFormats.count();
     // we expect a really small number of possible formats so linear search
     // should be OK
diff --git a/src/gpu/gl/GrGLCaps.h b/src/gpu/gl/GrGLCaps.h
index 920140f1e6..4599e57bdf 100644
--- a/src/gpu/gl/GrGLCaps.h
+++ b/src/gpu/gl/GrGLCaps.h
@@ -252,7 +252,7 @@ private:
             }
         }
 
-        static const int kNumUints = (kGrPixelConfigCount  + 31) / 32;
+        static const int kNumUints = (kGrPixelConfigCnt  + 31) / 32;
         uint32_t fVerifiedColorConfigs[kNumUints];
 
         void markVerified(GrPixelConfig config) {
diff --git a/src/gpu/gl/GrGLShaderBuilder.cpp b/src/gpu/gl/GrGLShaderBuilder.cpp
index 3808402ab4..a5c96c7dd6 100644
--- a/src/gpu/gl/GrGLShaderBuilder.cpp
+++ b/src/gpu/gl/GrGLShaderBuilder.cpp
@@ -40,10 +40,10 @@ inline const char* sample_function_name(GrSLType type, GrGLSLGeneration glslGen)
 inline bool swizzle_requires_alpha_remapping(const GrGLCaps& caps,
                                              const GrTextureAccess& access) {
     if (GrPixelConfigIsAlphaOnly(access.getTexture()->config())) {
-        if (caps.textureRedSupport() && (GrTextureAccess::kA_SwizzleFlag & access.swizzleMask())) {
+        if (caps.textureRedSupport() && (kA_GrColorComponentFlag & access.swizzleMask())) {
             return true;
         }
-        if (GrTextureAccess::kRGB_SwizzleMask & access.swizzleMask()) {
+        if (kRGB_GrColorComponentFlags & access.swizzleMask()) {
             return true;
         }
     }
@@ -51,14 +51,15 @@ inline bool swizzle_requires_alpha_remapping(const GrGLCaps& caps,
 }
 
 void append_swizzle(SkString* outAppend,
-                    const GrTextureAccess& access,
+                    const GrGLShaderBuilder::TextureSampler& texSampler,
                     const GrGLCaps& caps) {
-    const char* swizzle = access.getSwizzle();
+    const char* swizzle = texSampler.swizzle();
     char mangledSwizzle[5];
 
     // The swizzling occurs using texture params instead of shader-mangling if ARB_texture_swizzle
     // is available.
-    if (!caps.textureSwizzleSupport() && GrPixelConfigIsAlphaOnly(access.getTexture()->config())) {
+    if (!caps.textureSwizzleSupport() &&
+        (kA_GrColorComponentFlag == texSampler.configComponentMask())) {
         char alphaChar = caps.textureRedSupport() ? 'r' : 'a';
         int i;
         for (i = 0; '\0' != swizzle[i]; ++i) {
@@ -151,14 +152,13 @@ void GrGLShaderBuilder::appendTextureLookup(SkString* out,
                                             const GrGLShaderBuilder::TextureSampler& sampler,
                                             const char* coordName,
                                             GrSLType varyingType) const {
-    GrAssert(NULL != sampler.textureAccess());
     GrAssert(NULL != coordName);
 
     out->appendf("%s(%s, %s)",
                  sample_function_name(varyingType, fCtxInfo.glslGeneration()),
                  this->getUniformCStr(sampler.fSamplerUniform),
                  coordName);
-    append_swizzle(out, *sampler.textureAccess(), *fCtxInfo.caps());
+    append_swizzle(out, sampler, *fCtxInfo.caps());
 }
 
 void GrGLShaderBuilder::appendTextureLookup(ShaderType type,
@@ -191,17 +191,6 @@ GrBackendEffectFactory::EffectKey GrGLShaderBuilder::KeyForTextureAccess(
     if (!caps.textureSwizzleSupport() && swizzle_requires_alpha_remapping(caps, access)) {
         key = 1;
     }
-#if GR_DEBUG
-    // Assert that key is set iff the swizzle will be modified.
-    SkString origString(access.getSwizzle());
-    origString.prepend(".");
-    SkString modifiedString;
-    append_swizzle(&modifiedString, access, caps);
-    if (!modifiedString.size()) {
-        modifiedString = ".rgba";
-    }
-    GrAssert(SkToBool(key) == (modifiedString != origString));
-#endif
     return key;
 }
 
diff --git a/src/gpu/gl/GrGLShaderBuilder.h b/src/gpu/gl/GrGLShaderBuilder.h
index 9d64143802..d947771b3e 100644
--- a/src/gpu/gl/GrGLShaderBuilder.h
+++ b/src/gpu/gl/GrGLShaderBuilder.h
@@ -10,6 +10,7 @@
 
 #include "GrAllocator.h"
 #include "GrBackendEffectFactory.h"
+#include "GrColor.h"
 #include "GrEffect.h"
 #include "gl/GrGLSL.h"
 #include "gl/GrGLUniformManager.h"
@@ -31,31 +32,40 @@ public:
     class TextureSampler {
     public:
         TextureSampler()
-            : fTextureAccess(NULL)
-            , fSamplerUniform(GrGLUniformManager::kInvalidUniformHandle) {}
+            : fConfigComponentMask(0)
+            , fSamplerUniform(GrGLUniformManager::kInvalidUniformHandle) {
+            // we will memcpy the first 4 bytes from passed in swizzle. This ensures the string is
+            // terminated.
+            fSwizzle[4] = '\0';
+        }
 
         TextureSampler(const TextureSampler& other) { *this = other; }
 
         TextureSampler& operator= (const TextureSampler& other) {
-            GrAssert(NULL == fTextureAccess);
+            GrAssert(0 == fConfigComponentMask);
             GrAssert(GrGLUniformManager::kInvalidUniformHandle == fSamplerUniform);
 
-            fTextureAccess = other.fTextureAccess;
+            fConfigComponentMask = other.fConfigComponentMask;
             fSamplerUniform = other.fSamplerUniform;
             return *this;
         }
 
-        const GrTextureAccess* textureAccess() const { return fTextureAccess; }
+        // bitfield of GrColorComponentFlags present in the texture's config.
+        uint32_t configComponentMask() const { return fConfigComponentMask; }
+
+        const char* swizzle() const { return fSwizzle; }
 
     private:
         // The idx param is used to ensure multiple samplers within a single effect have unique
-        // uniform names.
-        void init(GrGLShaderBuilder* builder, const GrTextureAccess* access, int idx) {
-            GrAssert(NULL == fTextureAccess);
+        // uniform names. swizzle is a four char max string made up of chars 'r', 'g', 'b', and 'a'.
+        void init(GrGLShaderBuilder* builder,
+                  uint32_t configComponentMask,
+                  const char* swizzle,
+                  int idx) {
+            GrAssert(0 == fConfigComponentMask);
             GrAssert(GrGLUniformManager::kInvalidUniformHandle == fSamplerUniform);
 
             GrAssert(NULL != builder);
-            GrAssert(NULL != access);
             SkString name;
             name.printf("Sampler%d_", idx);
             fSamplerUniform = builder->addUniform(GrGLShaderBuilder::kFragment_ShaderType,
@@ -63,14 +73,23 @@ public:
                                                   name.c_str());
             GrAssert(GrGLUniformManager::kInvalidUniformHandle != fSamplerUniform);
 
-            fTextureAccess = access;
+            fConfigComponentMask = configComponentMask;
+            memcpy(fSwizzle, swizzle, 4);
+        }
+
+        void init(GrGLShaderBuilder* builder, const GrTextureAccess* access, int idx) {
+            GrAssert(NULL != access);
+            this->init(builder,
+                       GrPixelConfigComponentMask(access->getTexture()->config()),
+                       access->getSwizzle(),
+                       idx);
         }
 
-        const GrTextureAccess*            fTextureAccess;
+        uint32_t                          fConfigComponentMask;
+        char                              fSwizzle[5];
         GrGLUniformManager::UniformHandle fSamplerUniform;
 
-        friend class GrGLShaderBuilder; // to access fSamplerUniform
-        friend class GrGLProgram;       // to construct these and access fSamplerUniform.
+        friend class GrGLShaderBuilder; // to call init().
     };
 
     typedef SkTArray<TextureSampler> TextureSamplerArray;