Merge 92908 - Readback composited webgl results for printing

Source/WebCore/platform/graphics/chromium/WebGLLayerChromium.cpp

 /*
  * Copyright (C) 2010 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 79 matching lines @@
         // prepareTexture copies the contents of the off-screen render target into the texture
         // used by the compositor.
         //
         m_context->prepareTexture();
         m_context->markLayerComposited();
         m_contentsDirty = false;
         m_textureUpdated = false;
     }
 }
 
+bool WebGLLayerChromium::paintRenderedResultsToCanvas(ImageBuffer* imageBuffer)
+{
+    if (m_textureUpdated || !layerRenderer() || !drawsContent())
+        return false;
+
+    IntSize framebufferSize = m_context->getInternalFramebufferSize();
+    ASSERT(layerRendererContext());
+
+    // This would ideally be done in the webgl context, but that isn't possible yet.
+    Platform3DObject framebuffer = layerRendererContext()->createFramebuffer();
+    layerRendererContext()->bindFramebuffer(GraphicsContext3D::FRAMEBUFFER, framebuffer);
+    layerRendererContext()->framebufferTexture2D(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::COLOR_ATTACHMENT0, GraphicsContext3D::TEXTURE_2D, m_textureId, 0);
+
+    Extensions3DChromium* extensions = static_cast<Extensions3DChromium*>(layerRendererContext()->getExtensions());
+    extensions->paintFramebufferToCanvas(framebuffer, framebufferSize.width(), framebufferSize.height(), !m_context->getContextAttributes().premultipliedAlpha, imageBuffer);
+    layerRendererContext()->deleteFramebuffer(framebuffer);
+    return true;
+}
+
 void WebGLLayerChromium::setTextureUpdated()
 {
     m_textureUpdated = true;
     // If WebGL commands are issued outside of a the animation callbacks, then use
     // call rateLimitOffscreenContextCHROMIUM() to keep the context from getting too far ahead.
     if (layerRenderer() && !layerRenderer()->isAnimating() && m_contextSupportsRateLimitingExtension && !m_rateLimitingTimer.isActive())
         m_rateLimitingTimer.startOneShot(0);
 }
 
 void WebGLLayerChromium::setContext(const GraphicsContext3D* context)
@@ skipping 43 matching lines @@
 
     if (!m_context)
         return;
 
     Extensions3DChromium* extensions = static_cast<Extensions3DChromium*>(m_context->getExtensions());
     extensions->rateLimitOffscreenContextCHROMIUM();
 }
 
 }
 #endif // USE(ACCELERATED_COMPOSITING)