michael@0: /*
michael@0:  * Copyright 2012 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: #ifndef GrFakeRefObj_DEFINED
michael@0: #define GrFakeRefObj_DEFINED
michael@0: 
michael@0: #include "SkTypes.h"
michael@0: #include "gl/GrGLInterface.h"
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////
michael@0: // This object is used to track the OpenGL objects. We don't use real
michael@0: // reference counting (i.e., we don't free the objects when their ref count
michael@0: // goes to 0) so that we can detect invalid memory accesses. The refs we
michael@0: // are tracking in this class are actually OpenGL's references to the objects
michael@0: // not "ours"
michael@0: // Each object also gets a unique globally identifying ID
michael@0: class GrFakeRefObj : public SkNoncopyable {
michael@0: public:
michael@0:     GrFakeRefObj()
michael@0:         : fRef(0)
michael@0:         , fHighRefCount(0)
michael@0:         , fMarkedForDeletion(false)
michael@0:         , fDeleted(false) {
michael@0: 
michael@0:         // source for globally unique IDs - 0 is reserved!
michael@0:         static int fNextID = 0;
michael@0: 
michael@0:         fID = ++fNextID;
michael@0:     }
michael@0:     virtual ~GrFakeRefObj() {};
michael@0: 
michael@0:     void ref() {
michael@0:         fRef++;
michael@0:         if (fHighRefCount < fRef) {
michael@0:             fHighRefCount = fRef;
michael@0:         }
michael@0:     }
michael@0:     void unref() {
michael@0:         fRef--;
michael@0:         GrAlwaysAssert(fRef >= 0);
michael@0: 
michael@0:         // often in OpenGL a given object may still be in use when the
michael@0:         // delete call is made. In these cases the object is marked
michael@0:         // for deletion and then freed when it is no longer in use
michael@0:         if (0 == fRef && fMarkedForDeletion) {
michael@0:             this->deleteAction();
michael@0:         }
michael@0:     }
michael@0:     int getRefCount() const             { return fRef; }
michael@0:     int getHighRefCount() const         { return fHighRefCount; }
michael@0: 
michael@0:     GrGLuint getID() const              { return fID; }
michael@0: 
michael@0:     void setMarkedForDeletion()         { fMarkedForDeletion = true; }
michael@0:     bool getMarkedForDeletion() const   { return fMarkedForDeletion; }
michael@0: 
michael@0:     bool getDeleted() const             { return fDeleted; }
michael@0: 
michael@0:     // The deleteAction fires if the object has been marked for deletion but
michael@0:     // couldn't be deleted earlier due to refs
michael@0:     virtual void deleteAction() {
michael@0:         this->setDeleted();
michael@0:     }
michael@0: 
michael@0: protected:
michael@0: private:
michael@0:     int         fRef;               // ref count
michael@0:     int         fHighRefCount;      // high water mark of the ref count
michael@0:     GrGLuint    fID;                // globally unique ID
michael@0:     bool        fMarkedForDeletion;
michael@0:     // The deleted flag is only set when OpenGL thinks the object is deleted
michael@0:     // It is obviously still allocated w/in this framework
michael@0:     bool        fDeleted;
michael@0: 
michael@0:     // setDeleted should only ever appear in the deleteAction method!
michael@0:     void setDeleted()                   { fDeleted = true; }
michael@0: };
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////
michael@0: // Each class derived from GrFakeRefObj should use this macro to add a
michael@0: // factory creation entry point. This entry point is used by the GrGLDebug
michael@0: // object to instantiate the various objects
michael@0: // all globally unique IDs
michael@0: #define GR_DEFINE_CREATOR(className)                        \
michael@0:     public:                                                 \
michael@0:     static GrFakeRefObj *create ## className() {            \
michael@0:         return SkNEW(className);                            \
michael@0:     }
michael@0: 
michael@0: #endif // GrFakeRefObj_DEFINED