Implement WEBGL_shared_resources

Source/core/html/canvas/WebGLRenderingContext.h

Index: Source/core/html/canvas/WebGLRenderingContext.h
diff --git a/Source/core/html/canvas/WebGLRenderingContext.h b/Source/core/html/canvas/WebGLRenderingContext.h
index 358b94b3391948b660b60b701dd7877a3fab8189..8d8acf818e29ae9b0e8c6d1b3969b1cd84183847 100644
--- a/Source/core/html/canvas/WebGLRenderingContext.h
+++ b/Source/core/html/canvas/WebGLRenderingContext.h
@@ -80,6 +80,7 @@ class WebGLProgram;
 class WebGLRenderbuffer;
 class WebGLShader;
 class WebGLSharedObject;
+class WebGLSharedResources;
 class WebGLShaderPrecisionFormat;
 class WebGLTexture;
 class WebGLUniformLocation;
@@ -98,6 +99,10 @@ public:
     int drawingBufferWidth() const;
     int drawingBufferHeight() const;
 
+    unsigned contextIndex() const;
+    unsigned resourceSyncCount() const;
+    void flushResourceChanges();
+
     void activeTexture(GC3Denum texture, ExceptionCode&);
     void attachShader(WebGLProgram*, WebGLShader*, ExceptionCode&);
     void bindAttribLocation(WebGLProgram*, GC3Duint index, const String& name, ExceptionCode&);
@@ -196,7 +201,7 @@ public:
 
     void hint(GC3Denum target, GC3Denum mode);
     GC3Dboolean isBuffer(WebGLBuffer*);
-    bool isContextLost();
+    bool isContextLost() const;
     GC3Dboolean isEnabled(GC3Denum cap);
     GC3Dboolean isFramebuffer(WebGLFramebuffer*);
     GC3Dboolean isProgram(WebGLProgram*);
@@ -300,6 +305,10 @@ public:
 
     void viewport(GC3Dint x, GC3Dint y, GC3Dsizei width, GC3Dsizei height);
 
+    long acquireSharedResource(WebGLSharedObject*, WebGLSharedObject::AcquireMode, PassRefPtr<WebGLAcquireSharedResourceCallback>, ExceptionCode&);
+    void releaseSharedResource(WebGLSharedObject*, ExceptionCode&);
+    void cancelAcquireSharedResource(long);
+
     // WEBKIT_lose_context support
     enum LostContextMode {
         // Lost context occurred at the graphics system level.
@@ -334,6 +343,15 @@ public:
     virtual bool hasPendingActivity() const;
     virtual void stop();
 
+    enum ConsoleDisplayPreference {
+        DisplayInConsole,
+        DontDisplayInConsole
+    };
+
+    // Wrapper for GraphicsContext3D::synthesizeGLError that sends a message
+    // to the JavaScript console.
+    void synthesizeGLError(GC3Denum, const char* functionName, const char* description, ConsoleDisplayPreference = DisplayInConsole);
+
   private:
     friend class WebGLDrawBuffers;
     friend class WebGLFramebuffer;
@@ -346,7 +364,7 @@ public:
     friend class WebGLRenderingContextErrorMessageCallback;
     friend class WebGLVertexArrayObjectOES;
 
-    WebGLRenderingContext(HTMLCanvasElement*, PassRefPtr<GraphicsContext3D>, GraphicsContext3D::Attributes, GraphicsContext3D::Attributes);
+    WebGLRenderingContext(HTMLCanvasElement*, PassRefPtr<GraphicsContext3D>, GraphicsContext3D::Attributes, GraphicsContext3D::Attributes, PassRefPtr<WebGLContextGroup>);
     void initializeNewContext();
     void setupFlags();
 
@@ -369,12 +387,15 @@ public:
     // Check if each enabled vertex attribute is bound to a buffer.
     bool validateRenderingState();
 
-    bool validateWebGLObject(const char*, WebGLObject*);
+    bool validateWebGLContextObject(const char*, WebGLContextObject*);
+    bool validateWebGLSharedObject(const char*, WebGLSharedObject*, WebGLSharedObject::AcquireMode);
 
     // Adds a compressed texture format.
     void addCompressedTextureFormat(GC3Denum);
     void removeAllCompressedTextureFormats();
 
+    WebGLBuffer* getBufferForTarget(const char* functionName, GC3Denum target);
+
     PassRefPtr<Image> videoFrameToImage(HTMLVideoElement*, BackingStoreCopy, ExceptionCode&);
 
     WebGLRenderbuffer* ensureEmulatedStencilBuffer(GC3Denum target, WebGLRenderbuffer*);
@@ -527,6 +548,7 @@ public:
     RefPtr<WebGLCompressedTexturePVRTC> m_webglCompressedTexturePVRTC;
     RefPtr<WebGLCompressedTextureS3TC> m_webglCompressedTextureS3TC;
     RefPtr<WebGLDepthTexture> m_webglDepthTexture;
+    RefPtr<WebGLSharedResources> m_webglSharedResources;
 
     class ExtensionTracker {
     public:
@@ -639,6 +661,9 @@ public:
     WebGLGetInfo getWebGLFloatArrayParameter(GC3Denum);
     WebGLGetInfo getWebGLIntArrayParameter(GC3Denum);
 
+    bool isAcquiredForModification(const char*, WebGLSharedObject*);
+    bool isAcquiredForReading(const char*, WebGLSharedObject*);
+
     // Clear the backbuffer if it was composited since the last operation.
     // clearMask is set to the bitfield of any clear that would happen anyway at this time
     // and the function returns true if that clear is now unnecessary.
@@ -684,7 +709,7 @@ public:
     // Helper function to check target and texture bound to the target.
     // Generate GL errors and return 0 if target is invalid or texture bound is
     // null.  Otherwise, return the texture bound to the target.
-    WebGLTexture* validateTextureBinding(const char* functionName, GC3Denum target, bool useSixEnumsForCubeMap);
+    WebGLTexture* validateTextureBinding(const char* functionName, GC3Denum target, bool useSixEnumsForCubeMap, WebGLSharedObject::AcquireMode);
 
     // Helper function to check input format/type for functions {copy}Tex{Sub}Image.
     // Generates GL error and returns false if parameters are invalid.
@@ -828,12 +853,14 @@ public:
 
     // Helper function for delete* (deleteBuffer, deleteProgram, etc) functions.
     // Return false if caller should return without further processing.
-    bool deleteObject(WebGLObject*);
+    bool deleteContextObject(const char* functionName, WebGLContextObject*);
+    bool deleteSharedObject(const char* functionName, WebGLSharedObject*);
 
     // Helper function for bind* (bindBuffer, bindTexture, etc) and useProgram.
     // If the object has already been deleted, set deleted to true upon return.
     // Return false if caller should return without further processing.
-    bool checkObjectToBeBound(const char* functionName, WebGLObject*, bool& deleted);
+    bool checkContextObjectToBeBound(const char* functionName, WebGLContextObject*, bool& deleted);
+    bool checkSharedObjectToBeBound(const char* functionName, WebGLSharedObject*, bool& deleted, bool& boundSinceLastAcquire);
 
     void dispatchContextLostEvent(Timer<WebGLRenderingContext>*);
     // Helper for restoration after context lost.
@@ -843,15 +870,6 @@ public:
     // a Safari or Chrome extension.
     bool allowPrivilegedExtensions() const;
 
-    enum ConsoleDisplayPreference {
-        DisplayInConsole,
-        DontDisplayInConsole
-    };
-
-    // Wrapper for GraphicsContext3D::synthesizeGLError that sends a message
-    // to the JavaScript console.
-    void synthesizeGLError(GC3Denum, const char* functionName, const char* description, ConsoleDisplayPreference = DisplayInConsole);
-
     String ensureNotNull(const String&) const;
 
     // Enable or disable stencil test based on user setting and