The Tor Browser: gfx/skia/trunk/include/gpu/GrBackendEffectFactory.h@a63d609f5ebe

     1 /*

     2  * Copyright 2012 Google Inc.

     3  *

     4  * Use of this source code is governed by a BSD-style license that can be

     5  * found in the LICENSE file.

     6  */

     8 #ifndef GrBackendEffectFactory_DEFINED

     9 #define GrBackendEffectFactory_DEFINED

    11 #include "GrTypes.h"

    12 #include "SkTemplates.h"

    13 #include "SkThread.h"

    14 #include "SkTypes.h"

    16 /** Given a GrEffect of a particular type, creates the corresponding graphics-backend-specific

    17     effect object. Also tracks equivalence of shaders generated via a key. Each factory instance

    18     is assigned a generation ID at construction. The ID of the return of GrEffect::getFactory()

    19     is used as a type identifier. Thus a GrEffect subclass must return a singleton from

    20     getFactory(). GrEffect subclasses should use the derived class GrTBackendEffectFactory that is

    21     templated on the GrEffect subclass as their factory object. It requires that the GrEffect

    22     subclass has a nested class (or typedef) GLEffect which is its GL implementation and a subclass

    23     of GrGLEffect.

    24  */

    26 class GrEffectRef;

    27 class GrGLEffect;

    28 class GrGLCaps;

    29 class GrDrawEffect;

    31 class GrBackendEffectFactory : public SkNoncopyable {

    32 public:

    33     typedef uint32_t EffectKey;

    34     enum {

    35         kNoEffectKey = 0,

    36         kEffectKeyBits = 10,

    37         /**

    38          * The framework automatically includes coord transforms and texture accesses in their

    39          * effect's EffectKey, so effects don't need to account for them in GenKey().

    40          */

    41         kTextureKeyBits = 4,

    42         kTransformKeyBits = 6,

    43         kAttribKeyBits = 6,

    44         kClassIDBits = 6

    45     };

    47     virtual EffectKey glEffectKey(const GrDrawEffect&, const GrGLCaps&) const = 0;

    48     virtual GrGLEffect* createGLInstance(const GrDrawEffect&) const = 0;

    50     bool operator ==(const GrBackendEffectFactory& b) const {

    51         return fEffectClassID == b.fEffectClassID;

    52     }

    53     bool operator !=(const GrBackendEffectFactory& b) const {

    54         return !(*this == b);

    55     }

    57     virtual const char* name() const = 0;

    59     static EffectKey GetTransformKey(EffectKey key) {

    60         return key >> (kEffectKeyBits + kTextureKeyBits) & ((1U << kTransformKeyBits) - 1);

    61     }

    63 protected:

    64     enum {

    65         kIllegalEffectClassID = 0,

    66     };

    68     GrBackendEffectFactory() {

    69         fEffectClassID = kIllegalEffectClassID;

    70     }

    71     virtual ~GrBackendEffectFactory() {}

    73     static EffectKey GenID() {

    74         SkDEBUGCODE(static const int32_t kClassIDBits = 8 * sizeof(EffectKey) -

    75                            kTextureKeyBits - kEffectKeyBits - kAttribKeyBits);

    76         // fCurrEffectClassID has been initialized to kIllegalEffectClassID. The

    77         // atomic inc returns the old value not the incremented value. So we add

    78         // 1 to the returned value.

    79         int32_t id = sk_atomic_inc(&fCurrEffectClassID) + 1;

    80         SkASSERT(id < (1 << kClassIDBits));

    81         return static_cast<EffectKey>(id);

    82     }

    84     EffectKey fEffectClassID;

    86 private:

    87     static int32_t fCurrEffectClassID;

    88 };

    90 #endif

The Tor Browser / file revision