WebGL: accelerated texImage2D and texSubImage2D for canvas

Source/core/html/canvas/WebGLRenderingContextBase.h

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 713 matching lines @@
     void restoreStateAfterClear();
 
     // Convert texture internal format.
     GLenum convertTexInternalFormat(GLenum internalformat, GLenum type);
 
     void texImage2DBase(GLenum target, GLint level, GLenum internalformat, GLsizei width, GLsizei height, GLint border, GLenum format, GLenum type, const void* pixels, ExceptionState&);
     void texImage2DImpl(GLenum target, GLint level, GLenum internalformat, GLenum format, GLenum type, Image*, WebGLImageConversion::ImageHtmlDomSource, bool flipY, bool premultiplyAlpha, ExceptionState&);
     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();
 
     // Helper function for copyTex{Sub}Image, check whether the internalformat
     // and the color buffer format of the current bound framebuffer combination
     // is valid.
     bool isTexInternalFormatColorBufferCombinationValid(GLenum texInternalFormat, GLenum colorBufferFormat);
 
     // Helper function to get the bound framebuffer's color buffer format.
     GLenum boundFramebufferColorFormat();
@@ skipping 19 matching lines @@
     bool validateTexFuncFormatAndType(const char* functionName, GLenum format, GLenum type, GLint level);
 
     // Helper function to check input level for functions {copy}Tex{Sub}Image.
     // Generates GL error and returns false if level is invalid.
     bool validateTexFuncLevel(const char* functionName, GLenum target, GLint level);
 
     // Helper function to check if a 64-bit value is non-negative and can fit into a 32-bit integer.
     // 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,
         SourceHTMLImageElement,
         SourceHTMLCanvasElement,
         SourceHTMLVideoElement,
     };
 
     // 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,
         NullNotAllowed
     };
 
     // Helper function to validate that the given ArrayBufferView
     // is of the correct type and contains enough data for the texImage call.
     // Generates GL error and returns false if parameters are invalid.
     bool validateTexFuncData(const char* functionName, GLint level, GLsizei width, GLsizei height, GLenum format, GLenum type, DOMArrayBufferView* pixels, NullDisposition);
 
     // Helper function to validate a given texture format is settable as in
     // you can supply data to texImage2D, or call texImage2D, copyTexImage2D and
     // copyTexSubImage2D.
     // Generates GL error and returns false if the format is not settable.
     bool validateSettableTexFormat(const char* functionName, GLenum format);
 
     // Helper function to validate compressed texture data is correct size
     // for the given format and dimensions.
     bool validateCompressedTexFuncData(const char* functionName, GLsizei width, GLsizei height, GLenum format, DOMArrayBufferView* pixels);
 
     // Helper function for validating compressed texture formats.
     bool validateCompressedTexFormat(GLenum format);
 
     // 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.
     bool validateCompressedTexSubDimensions(const char* functionName, GLenum target, GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, WebGLTexture*);
 
     // Helper function to validate mode for draw{Arrays/Elements}.
     bool validateDrawMode(const char* functionName, GLenum);
 
     // Helper function to validate if front/back stencilMask and stencilFunc settings are the same.
     bool validateStencilSettings(const char* functionName);
@@ skipping 129 matching lines @@
     static IntSize oldestContextSize();
 };
 
 DEFINE_TYPE_CASTS(WebGLRenderingContextBase, CanvasRenderingContext, context, context->is3d(), context.is3d());
 
 } // namespace blink
 
 WTF_ALLOW_MOVE_INIT_AND_COMPARE_WITH_MEM_FUNCTIONS(blink::WebGLRenderingContextBase::TextureUnitState);
 
 #endif // WebGLRenderingContextBase_h