void LayerRendererChromium::drawLayer(CCLayerImpl* layer, RenderSurfaceChromium* targetSurface)
{
if (layer->renderSurface() && layer->renderSurface() != targetSurface) {
layer->renderSurface()->draw(layer->getDrawRect());
return;
}
if (!layer->drawsContent())
return;
if (layer->bounds().isEmpty()) {
layer->unreserveContentsTexture();
return;
}
setScissorToRect(layer->scissorRect());
IntRect targetSurfaceRect = m_currentRenderSurface ? m_currentRenderSurface->contentRect() : m_defaultRenderSurface->contentRect();
IntRect scissorRect = layer->scissorRect();
if (!scissorRect.isEmpty())
targetSurfaceRect.intersect(scissorRect);
// Check if the layer falls within the visible bounds of the page.
IntRect layerRect = layer->getDrawRect();
bool isLayerVisible = targetSurfaceRect.intersects(layerRect);
if (!isLayerVisible) {
layer->unreserveContentsTexture();
return;
}
// FIXME: Need to take into account the commulative render surface transforms all the way from
// the default render surface in order to determine visibility.
TransformationMatrix combinedDrawMatrix = (layer->targetRenderSurface() ? layer->targetRenderSurface()->drawTransform().multiply(layer->drawTransform()) : layer->drawTransform());
if (!layer->doubleSided()) {
FloatRect layerRect(FloatPoint(0, 0), FloatSize(layer->bounds()));
FloatQuad mappedLayer = combinedDrawMatrix.mapQuad(FloatQuad(layerRect));
FloatSize horizontalDir = mappedLayer.p2() - mappedLayer.p1();
FloatSize verticalDir = mappedLayer.p4() - mappedLayer.p1();
FloatPoint3D xAxis(horizontalDir.width(), horizontalDir.height(), 0);
FloatPoint3D yAxis(verticalDir.width(), verticalDir.height(), 0);
FloatPoint3D zAxis = xAxis.cross(yAxis);
if (zAxis.z() < 0) {
layer->unreserveContentsTexture();
return;
}
}
layer->draw(targetSurfaceRect);
// Draw the debug border if there is one.
layer->drawDebugBorder();
}
void LayerRendererChromium::drawLayer(CCLayerImpl* layer, CCRenderSurface* targetSurface)
{
if (layer->renderSurface() && layer->renderSurface() != targetSurface) {
layer->renderSurface()->draw(this, layer->getDrawRect());
layer->renderSurface()->releaseContentsTexture();
return;
}
if (!layer->drawsContent())
return;
if (!layer->opacity())
return;
if (layer->bounds().isEmpty())
return;
IntRect targetSurfaceRect = layer->targetRenderSurface() ? layer->targetRenderSurface()->contentRect() : m_defaultRenderSurface->contentRect();
if (layer->usesLayerScissor()) {
IntRect scissorRect = layer->scissorRect();
targetSurfaceRect.intersect(scissorRect);
if (targetSurfaceRect.isEmpty())
return;
setScissorToRect(scissorRect);
} else
GLC(m_context.get(), m_context->disable(GraphicsContext3D::SCISSOR_TEST));
IntRect visibleLayerRect = CCLayerTreeHostCommon::calculateVisibleLayerRect(targetSurfaceRect, layer->bounds(), layer->contentBounds(), layer->drawTransform());
visibleLayerRect.move(toSize(layer->scrollPosition()));
layer->setVisibleLayerRect(visibleLayerRect);
// The layer should not be drawn if (1) it is not double-sided and (2) the back of the layer is facing the screen.
// This second condition is checked by computing the transformed normal of the layer.
if (!layer->doubleSided()) {
FloatRect layerRect(FloatPoint(0, 0), FloatSize(layer->bounds()));
FloatQuad mappedLayer = layer->screenSpaceTransform().mapQuad(FloatQuad(layerRect));
FloatSize horizontalDir = mappedLayer.p2() - mappedLayer.p1();
FloatSize verticalDir = mappedLayer.p4() - mappedLayer.p1();
FloatPoint3D xAxis(horizontalDir.width(), horizontalDir.height(), 0);
FloatPoint3D yAxis(verticalDir.width(), verticalDir.height(), 0);
FloatPoint3D zAxis = xAxis.cross(yAxis);
if (zAxis.z() < 0)
return;
}
layer->draw(this);
// Draw the debug border if there is one.
layer->drawDebugBorder(this);
}