WebGL: accelerated texImage2D and texSubImage2D for canvas

Source/core/html/canvas/WebGLRenderingContextBase.h

Index: Source/core/html/canvas/WebGLRenderingContextBase.h
diff --git a/Source/core/html/canvas/WebGLRenderingContextBase.h b/Source/core/html/canvas/WebGLRenderingContextBase.h
index c3b0fa128e4e79f5e292362425a9efdc794445dd..38c58db2916edecd37ac912a9eacf6857a440b15 100644
--- a/Source/core/html/canvas/WebGLRenderingContextBase.h
+++ b/Source/core/html/canvas/WebGLRenderingContextBase.h
@@ -742,6 +742,14 @@ protected:
     void texSubImage2DBase(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLenum type, const void* pixels, ExceptionState&);
     void texSubImage2DImpl(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLenum format, GLenum type, Image*, WebGLImageConversion::ImageHtmlDomSource, bool flipY, bool premultiplyAlpha, ExceptionState&);
 
+    enum TexImageFunctionType {
+        NotTexSubImage2D,
+        TexSubImage2D,
+    };
+    // Copy from the canvas element directly to the texture via the GPU, without a read-back to system memory.
+    void texImage2DCanvasByGPU(TexImageFunctionType, WebGLTexture*, GLenum target, GLint level,
+        GLenum internalformat, GLenum type, GLint xoffset, GLint yoffset, HTMLCanvasElement*);
+
     void handleTextureCompleteness(const char*, bool);
     void createFallbackBlackTextures1x1();
 
@@ -781,11 +789,6 @@ protected:
     // Generates GL error and returns false if not.
     bool validateValueFitNonNegInt32(const char* functionName, const char* paramName, long long value);
 
-    enum TexFuncValidationFunctionType {
-        NotTexSubImage2D,
-        TexSubImage2D,
-    };
-
     enum TexFuncValidationSourceType {
         SourceArrayBufferView,
         SourceImageData,
@@ -796,16 +799,16 @@ protected:
 
     // Helper function for tex{Sub}Image2D to check if the input format/type/level/target/width/height/border/xoffset/yoffset are valid.
     // Otherwise, it would return quickly without doing other work.
-    bool validateTexFunc(const char* functionName, TexFuncValidationFunctionType, TexFuncValidationSourceType, GLenum target, GLint level, GLenum internalformat, GLsizei width,
+    bool validateTexFunc(const char* functionName, TexImageFunctionType, TexFuncValidationSourceType, GLenum target, GLint level, GLenum internalformat, GLsizei width,
         GLsizei height, GLint border, GLenum format, GLenum type, GLint xoffset, GLint yoffset);
 
     // Helper function to check input width and height for functions {copy, compressed}Tex{Sub}Image.
     // Generates GL error and returns false if width or height is invalid.
-    bool validateTexFuncDimensions(const char* functionName, TexFuncValidationFunctionType, GLenum target, GLint level, GLsizei width, GLsizei height);
+    bool validateTexFuncDimensions(const char* functionName, TexImageFunctionType, GLenum target, GLint level, GLsizei width, GLsizei height);
 
     // Helper function to check input parameters for functions {copy}Tex{Sub}Image.
     // Generates GL error and returns false if parameters are invalid.
-    bool validateTexFuncParameters(const char* functionName, TexFuncValidationFunctionType, GLenum target, GLint level, GLenum internalformat, GLsizei width, GLsizei height, GLint border, GLenum format, GLenum type);
+    bool validateTexFuncParameters(const char* functionName, TexImageFunctionType, GLenum target, GLint level, GLenum internalformat, GLsizei width, GLsizei height, GLint border, GLenum format, GLenum type);
 
     enum NullDisposition {
         NullAllowed,
@@ -832,7 +835,7 @@ protected:
 
     // Helper function to validate compressed texture dimensions are valid for
     // the given format.
-    bool validateCompressedTexDimensions(const char* functionName, TexFuncValidationFunctionType, GLenum target, GLint level, GLsizei width, GLsizei height, GLenum format);
+    bool validateCompressedTexDimensions(const char* functionName, TexImageFunctionType, GLenum target, GLint level, GLsizei width, GLsizei height, GLenum format);
 
     // Helper function to validate compressed texture dimensions are valid for
     // the given format.