void LayerRendererChromium::drawLayersInternal()
{
if (viewportSize().isEmpty() || !rootLayer())
return;
TRACE_EVENT("LayerRendererChromium::drawLayers", this, 0);
CCLayerImpl* rootDrawLayer = rootLayer();
makeContextCurrent();
if (!rootDrawLayer->renderSurface())
rootDrawLayer->createRenderSurface();
rootDrawLayer->renderSurface()->setContentRect(IntRect(IntPoint(), viewportSize()));
rootDrawLayer->setScissorRect(IntRect(IntPoint(), viewportSize()));
CCLayerList renderSurfaceLayerList;
renderSurfaceLayerList.append(rootDrawLayer);
m_defaultRenderSurface = rootDrawLayer->renderSurface();
m_defaultRenderSurface->clearLayerList();
{
TRACE_EVENT("LayerRendererChromium::drawLayersInternal::calcDrawEtc", this, 0);
CCLayerTreeHostCommon::calculateDrawTransformsAndVisibility(rootDrawLayer, rootDrawLayer, m_zoomAnimatorTransform, m_zoomAnimatorTransform, renderSurfaceLayerList, m_defaultRenderSurface->layerList(), &m_layerSorter, m_capabilities.maxTextureSize);
}
// The GL viewport covers the entire visible area, including the scrollbars.
GLC(m_context.get(), m_context->viewport(0, 0, viewportWidth(), viewportHeight()));
m_windowMatrix = screenMatrix(0, 0, viewportWidth(), viewportHeight());
// Bind the common vertex attributes used for drawing all the layers.
m_sharedGeometry->prepareForDraw();
GLC(m_context.get(), m_context->disable(GraphicsContext3D::SCISSOR_TEST));
GLC(m_context.get(), m_context->disable(GraphicsContext3D::DEPTH_TEST));
GLC(m_context.get(), m_context->disable(GraphicsContext3D::CULL_FACE));
useRenderSurface(m_defaultRenderSurface);
if (m_zoomAnimatorTransform.isIdentity())
// Clear to blue to make it easier to spot unrendered regions.
m_context->clearColor(0, 0, 1, 1);
else
// Clear to grey, as zoom animation may leave unrendered regions.
// FIXME(wjmaclean): Render some interesting texture in unrendered regions.
m_context->clearColor(0.25, 0.25, 0.25, 1);
m_context->colorMask(true, true, true, true);
m_context->clear(GraphicsContext3D::COLOR_BUFFER_BIT);
GLC(m_context.get(), m_context->enable(GraphicsContext3D::BLEND));
GLC(m_context.get(), m_context->blendFunc(GraphicsContext3D::ONE, GraphicsContext3D::ONE_MINUS_SRC_ALPHA));
GLC(m_context.get(), m_context->enable(GraphicsContext3D::SCISSOR_TEST));
// Update the contents of the render surfaces. We traverse the array from
// back to front to guarantee that nested render surfaces get rendered in the
// correct order.
for (int surfaceIndex = renderSurfaceLayerList.size() - 1; surfaceIndex >= 0 ; --surfaceIndex) {
CCLayerImpl* renderSurfaceLayer = renderSurfaceLayerList[surfaceIndex].get();
CCRenderSurface* renderSurface = renderSurfaceLayer->renderSurface();
ASSERT(renderSurface);
renderSurface->setSkipsDraw(true);
// Render surfaces whose drawable area has zero width or height
// will have no layers associated with them and should be skipped.
if (!renderSurface->layerList().size())
continue;
// Skip completely transparent render surfaces.
if (!renderSurface->drawOpacity())
continue;
if (useRenderSurface(renderSurface)) {
renderSurface->setSkipsDraw(false);
if (renderSurfaceLayer != rootDrawLayer) {
GLC(m_context.get(), m_context->disable(GraphicsContext3D::SCISSOR_TEST));
GLC(m_context.get(), m_context->clearColor(0, 0, 0, 0));
GLC(m_context.get(), m_context->clear(GraphicsContext3D::COLOR_BUFFER_BIT));
GLC(m_context.get(), m_context->enable(GraphicsContext3D::SCISSOR_TEST));
}
const CCLayerList& layerList = renderSurface->layerList();
for (unsigned layerIndex = 0; layerIndex < layerList.size(); ++layerIndex)
drawLayer(layerList[layerIndex].get(), renderSurface);
}
}
if (m_headsUpDisplay->enabled()) {
GLC(m_context.get(), m_context->enable(GraphicsContext3D::BLEND));
GLC(m_context.get(), m_context->blendFunc(GraphicsContext3D::ONE, GraphicsContext3D::ONE_MINUS_SRC_ALPHA));
GLC(m_context.get(), m_context->disable(GraphicsContext3D::SCISSOR_TEST));
useRenderSurface(m_defaultRenderSurface);
m_headsUpDisplay->draw();
}
GLC(m_context.get(), m_context->disable(GraphicsContext3D::SCISSOR_TEST));
GLC(m_context.get(), m_context->disable(GraphicsContext3D::BLEND));
}
void LayerRendererChromium::updateLayers(LayerList& renderSurfaceLayerList)
{
TRACE_EVENT("LayerRendererChromium::updateLayers", this, 0);
CCLayerImpl* rootDrawLayer = m_rootLayer->ccLayerImpl();
if (!rootDrawLayer->renderSurface())
rootDrawLayer->createRenderSurface();
ASSERT(rootDrawLayer->renderSurface());
rootDrawLayer->renderSurface()->m_contentRect = IntRect(IntPoint(0, 0), m_viewportVisibleRect.size());
IntRect rootScissorRect(m_viewportVisibleRect);
// The scissorRect should not include the scroll offset.
rootScissorRect.move(-m_viewportScrollPosition.x(), -m_viewportScrollPosition.y());
rootDrawLayer->setScissorRect(rootScissorRect);
m_defaultRenderSurface = rootDrawLayer->renderSurface();
renderSurfaceLayerList.append(rootDrawLayer);
TransformationMatrix identityMatrix;
m_defaultRenderSurface->m_layerList.clear();
// Unfortunately, updatePropertiesAndRenderSurfaces() currently both updates the layers and updates the draw state
// (transforms, etc). It'd be nicer if operations on the presentation layers happened later, but the draw
// transforms are needed by large layers to determine visibility. Tiling will fix this by eliminating the
// concept of a large content layer.
updatePropertiesAndRenderSurfaces(rootDrawLayer, identityMatrix, renderSurfaceLayerList, m_defaultRenderSurface->m_layerList);
#ifndef NDEBUG
s_inPaintLayerContents = true;
#endif
paintLayerContents(renderSurfaceLayerList);
#ifndef NDEBUG
s_inPaintLayerContents = false;
#endif
// FIXME: Before updateCompositorResourcesRecursive, when the compositor runs in
// its own thread, and when the copyTexImage2D bug is fixed, insert
// a glWaitLatch(Compositor->Offscreen) on all child contexts here instead
// of after updateCompositorResourcesRecursive.
// Also uncomment the glSetLatch(Compositor->Offscreen) code in addChildContext.
// if (hardwareCompositing() && m_contextSupportsLatch) {
// // For each child context:
// // glWaitLatch(Compositor->Offscreen);
// ChildContextMap::iterator i = m_childContexts.begin();
// for (; i != m_childContexts.end(); ++i) {
// Extensions3DChromium* ext = static_cast<Extensions3DChromium*>(i->first->getExtensions());
// GC3Duint childToParentLatchId, parentToChildLatchId;
// ext->getParentToChildLatchCHROMIUM(&parentToChildLatchId);
// ext->waitLatchCHROMIUM(parentToChildLatchId);
// }
// }
updateCompositorResourcesRecursive(m_rootLayer.get());
// After updateCompositorResourcesRecursive, set/wait latches for all child
// contexts. This will prevent the compositor from using any of the child
// parent textures while WebGL commands are executing from javascript *and*
// while the final parent texture is being blit'd. copyTexImage2D
// uses the parent texture as a temporary resolve buffer, so that's why the
// waitLatch is below, to block the compositor from using the parent texture
// until the next WebGL SwapBuffers (or copyTextureToParentTexture for
// Canvas2D).
if (hardwareCompositing() && m_contextSupportsLatch) {
m_childContextsWereCopied = true;
// For each child context:
// glSetLatch(Offscreen->Compositor);
// glWaitLatch(Compositor->Offscreen);
ChildContextMap::iterator i = m_childContexts.begin();
for (; i != m_childContexts.end(); ++i) {
Extensions3DChromium* ext = static_cast<Extensions3DChromium*>(i->first->getExtensions());
GC3Duint childToParentLatchId, parentToChildLatchId;
ext->getParentToChildLatchCHROMIUM(&parentToChildLatchId);
ext->getChildToParentLatchCHROMIUM(&childToParentLatchId);
ext->setLatchCHROMIUM(childToParentLatchId);
ext->waitLatchCHROMIUM(parentToChildLatchId);
}
}
}