Use GL_chromium_color_buffer_float extensions

Source/core/html/canvas/WebGLRenderingContext.cpp

 /*
  * 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 3295 matching lines @@
     m_context->stencilOp(fail, zfail, zpass);
 }
 
 void WebGLRenderingContext::stencilOpSeparate(GLenum face, GLenum fail, GLenum zfail, GLenum zpass)
 {
     if (isContextLost())
         return;
     m_context->stencilOpSeparate(face, fail, zfail, zpass);
 }
 
+GLenum WebGLRenderingContext::convertTexInternalFormat(GLenum internalformat, GLenum type)
+{
+    // Convert to sized internal formats that are renderable with GL_CHROMIUM_color_buffer_float_rgb(a).
+    if (type == GL_FLOAT && internalformat == GL_RGBA
+        && m_contextSupport->isExtensionEnabled("GL_CHROMIUM_color_buffer_float_rgba"))
+        return GL_RGBA32F_EXT;
+    if (type == GL_FLOAT && internalformat == GL_RGB
+        && m_contextSupport->isExtensionEnabled("GL_CHROMIUM_color_buffer_float_rgb"))
+        return GL_RGB32F_EXT;
+    return internalformat;

[Ken Russell (switch to Gerrit), 2014/02/11 23:46:52]

There aren't any queries whose results need to be fixed up in the opposite
direction?

[oetuaho-nv, 2014/02/12 12:45:36]

I couldn't find any other calls where conversions should be needed by looking
through the API.

+}
+
 void WebGLRenderingContext::texImage2DBase(GLenum target, GLint level, GLenum internalformat, GLsizei width, GLsizei height, GLint border, GLenum format, GLenum type, const void* pixels, ExceptionState& exceptionState)
 {
     // All calling functions check isContextLost, so a duplicate check is not needed here.
     // FIXME: Handle errors.
     WebGLTexture* tex = validateTextureBinding("texImage2D", target, true);
     ASSERT(validateTexFuncParameters("texImage2D", NotTexSubImage2D, target, level, internalformat, width, height, border, format, type));
     ASSERT(tex);
     ASSERT(!level || !WebGLTexture::isNPOT(width, height));
     ASSERT(!pixels || validateSettableTexFormat("texImage2D", internalformat));
-    m_context->texImage2D(target, level, internalformat, width, height,
-                          border, format, type, pixels);
+    m_context->texImage2D(target, level, convertTexInternalFormat(internalformat, type), width, height, border, format, type, pixels);
     tex->setLevelInfo(target, level, internalformat, width, height, type);
 }
 
 void WebGLRenderingContext::texImage2DImpl(GLenum target, GLint level, GLenum internalformat, GLenum format, GLenum type, Image* image, GraphicsContext3D::ImageHtmlDomSource domSource, bool flipY, bool premultiplyAlpha, ExceptionState& exceptionState)
 {
     // All calling functions check isContextLost, so a duplicate check is not needed here.
     Vector<uint8_t> data;
     GraphicsContext3D::ImageExtractor imageExtractor(image, domSource, premultiplyAlpha, m_unpackColorspaceConversion == GL_NONE);
     if (!imageExtractor.extractSucceeded()) {
         synthesizeGLError(GL_INVALID_VALUE, "texImage2D", "bad image data");
@@ skipping 2313 matching lines @@
         if (m_textureUnits[i].m_texture2DBinding
             || m_textureUnits[i].m_textureCubeMapBinding) {
             m_onePlusMaxNonDefaultTextureUnit = i + 1;
             return;
         }
     }
     m_onePlusMaxNonDefaultTextureUnit = 0;
 }
 
 } // namespace WebCore