Make GPU coord transforms automatic

include/gpu/GrBackendEffectFactory.h

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrBackendEffectFactory_DEFINED
 #define GrBackendEffectFactory_DEFINED
 
@@ skipping 15 matching lines @@
 class GrEffectRef;
 class GrGLEffect;
 class GrGLCaps;
 class GrDrawEffect;
 
 class GrBackendEffectFactory : public SkNoncopyable {
 public:
     typedef uint32_t EffectKey;
     enum {
         kNoEffectKey = 0,
-        kEffectKeyBits = 15,
+        kEffectKeyBits = 10,
         /**
-         * Some aspects of the generated code may be determined by the particular textures that are
-         * associated with the effect. These manipulations are performed by GrGLShaderBuilder beyond
-         * GrGLEffects' control. So there is a dedicated part of the key which is combined
-         * automatically with the bits produced by GrGLEffect::GenKey().
+         * The framework automatically includes coord transforms and texture accesses in their
+         * effect's EffectKey, so effects don't need to account for them in GenKey().
          */
         kTextureKeyBits = 4,
-        kAttribKeyBits = 6
+        kTransformKeyBits = 6,
+        kAttribKeyBits = 6,
+        kClassIDBits = 6
     };
 
     virtual EffectKey glEffectKey(const GrDrawEffect&, const GrGLCaps&) const = 0;
     virtual GrGLEffect* createGLInstance(const GrDrawEffect&) const = 0;
 
     bool operator ==(const GrBackendEffectFactory& b) const {
         return fEffectClassID == b.fEffectClassID;
     }
     bool operator !=(const GrBackendEffectFactory& b) const {
         return !(*this == b);
     }
 
     virtual const char* name() const = 0;
 
+    static EffectKey GetTransformKey(EffectKey key) {
+        return key >> (kEffectKeyBits + kTextureKeyBits) & ((1U << kTransformKeyBits) - 1);
+    }
+
 protected:
     enum {
         kIllegalEffectClassID = 0,
     };
 
     GrBackendEffectFactory() {
         fEffectClassID = kIllegalEffectClassID;
     }
     virtual ~GrBackendEffectFactory() {}
 
     static EffectKey GenID() {
         SkDEBUGCODE(static const int32_t kClassIDBits = 8 * sizeof(EffectKey) -
                            kTextureKeyBits - kEffectKeyBits - kAttribKeyBits);
         // fCurrEffectClassID has been initialized to kIllegalEffectClassID. The
         // atomic inc returns the old value not the incremented value. So we add
         // 1 to the returned value.
         int32_t id = sk_atomic_inc(&fCurrEffectClassID) + 1;
         SkASSERT(id < (1 << kClassIDBits));
         return static_cast<EffectKey>(id);
     }
 
     EffectKey fEffectClassID;
 
 private:
     static int32_t fCurrEffectClassID;
 };
 
 #endif