void CompositingLayerAssigner::assignLayersToBackingsInternal(PaintLayer* layer, SquashingState& squashingState, Vector<PaintLayer*>& layersNeedingPaintInvalidation)
{
if (requiresSquashing(layer->compositingReasons())) {
CompositingReasons reasonsPreventingSquashing = getReasonsPreventingSquashing(layer, squashingState);
if (reasonsPreventingSquashing)
layer->setCompositingReasons(layer->compositingReasons() | reasonsPreventingSquashing);
}
CompositingStateTransitionType compositedLayerUpdate = computeCompositedLayerUpdate(layer);
if (m_compositor->allocateOrClearCompositedLayerMapping(layer, compositedLayerUpdate)) {
TRACE_LAYER_INVALIDATION(layer, InspectorLayerInvalidationTrackingEvent::NewCompositedLayer);
layersNeedingPaintInvalidation.append(layer);
m_layersChanged = true;
if (ScrollingCoordinator* scrollingCoordinator = scrollingCoordinatorFromLayer(*layer)) {
if (layer->layoutObject()->style()->hasViewportConstrainedPosition())
scrollingCoordinator->frameViewFixedObjectsDidChange(layer->layoutObject()->view()->frameView());
}
}
// FIXME: special-casing reflection layers here is not right.
if (layer->reflectionInfo())
assignLayersToBackingsForReflectionLayer(layer->reflectionInfo()->reflectionLayer(), layersNeedingPaintInvalidation);
// Add this layer to a squashing backing if needed.
updateSquashingAssignment(layer, squashingState, compositedLayerUpdate, layersNeedingPaintInvalidation);
const bool layerIsSquashed = compositedLayerUpdate == PutInSquashingLayer || (compositedLayerUpdate == NoCompositingStateChange && layer->groupedMapping());
if (layerIsSquashed) {
squashingState.nextSquashedLayerIndex++;
IntRect layerBounds = layer->clippedAbsoluteBoundingBox();
squashingState.totalAreaOfSquashedRects += layerBounds.size().area();
squashingState.boundingRect.unite(layerBounds);
}
if (layer->stackingNode()->isStackingContext()) {
PaintLayerStackingNodeIterator iterator(*layer->stackingNode(), NegativeZOrderChildren);
while (PaintLayerStackingNode* curNode = iterator.next())
assignLayersToBackingsInternal(curNode->layer(), squashingState, layersNeedingPaintInvalidation);
}
// At this point, if the layer is to be separately composited, then its backing becomes the most recent in paint-order.
if (layer->compositingState() == PaintsIntoOwnBacking) {
ASSERT(!requiresSquashing(layer->compositingReasons()));
squashingState.updateSquashingStateForNewMapping(layer->compositedLayerMapping(), layer->hasCompositedLayerMapping());
}
if (layer->scrollParent())
layer->scrollParent()->scrollableArea()->setTopmostScrollChild(layer);
if (layer->needsCompositedScrolling())
layer->scrollableArea()->setTopmostScrollChild(nullptr);
PaintLayerStackingNodeIterator iterator(*layer->stackingNode(), NormalFlowChildren | PositiveZOrderChildren);
while (PaintLayerStackingNode* curNode = iterator.next())
assignLayersToBackingsInternal(curNode->layer(), squashingState, layersNeedingPaintInvalidation);
if (squashingState.hasMostRecentMapping && &squashingState.mostRecentMapping->owningLayer() == layer)
squashingState.haveAssignedBackingsToEntireSquashingLayerSubtree = true;
}
void CompositingLayerAssigner::updateSquashingAssignment(DeprecatedPaintLayer* layer, SquashingState& squashingState, const CompositingStateTransitionType compositedLayerUpdate,
Vector<DeprecatedPaintLayer*>& layersNeedingPaintInvalidation)
{
// NOTE: In the future as we generalize this, the background of this layer may need to be assigned to a different backing than
// the squashed DeprecatedPaintLayer's own primary contents. This would happen when we have a composited negative z-index element that needs
// to paint on top of the background, but below the layer's main contents. For now, because we always composite layers
// when they have a composited negative z-index child, such layers will never need squashing so it is not yet an issue.
if (compositedLayerUpdate == PutInSquashingLayer) {
// A layer that is squashed with other layers cannot have its own CompositedDeprecatedPaintLayerMapping.
ASSERT(!layer->hasCompositedDeprecatedPaintLayerMapping());
ASSERT(squashingState.hasMostRecentMapping);
bool changedSquashingLayer =
squashingState.mostRecentMapping->updateSquashingLayerAssignment(layer, squashingState.nextSquashedLayerIndex);
if (!changedSquashingLayer)
return;
// If we've modified the collection of squashed layers, we must update
// the graphics layer geometry.
squashingState.mostRecentMapping->setNeedsGraphicsLayerUpdate(GraphicsLayerUpdateSubtree);
layer->clipper().clearClipRectsIncludingDescendants();
// Issue a paint invalidation, since |layer| may have been added to an already-existing squashing layer.
TRACE_LAYER_INVALIDATION(layer, InspectorLayerInvalidationTrackingEvent::AddedToSquashingLayer);
layersNeedingPaintInvalidation.append(layer);
m_layersChanged = true;
} else if (compositedLayerUpdate == RemoveFromSquashingLayer) {
if (layer->groupedMapping()) {
// Before removing |layer| from an already-existing squashing layer that may have other content, issue a paint invalidation.
m_compositor->paintInvalidationOnCompositingChange(layer);
layer->groupedMapping()->setNeedsGraphicsLayerUpdate(GraphicsLayerUpdateSubtree);
layer->setGroupedMapping(nullptr, DeprecatedPaintLayer::InvalidateLayerAndRemoveFromMapping);
}
// If we need to issue paint invalidations, do so now that we've removed it from a squashed layer.
TRACE_LAYER_INVALIDATION(layer, InspectorLayerInvalidationTrackingEvent::RemovedFromSquashingLayer);
layersNeedingPaintInvalidation.append(layer);
m_layersChanged = true;
layer->setLostGroupedMapping(false);
}
}
void CompositingLayerAssigner::assignLayersToBackingsForReflectionLayer(DeprecatedPaintLayer* reflectionLayer, Vector<DeprecatedPaintLayer*>& layersNeedingPaintInvalidation)
{
CompositingStateTransitionType compositedLayerUpdate = computeCompositedLayerUpdate(reflectionLayer);
if (compositedLayerUpdate != NoCompositingStateChange) {
TRACE_LAYER_INVALIDATION(reflectionLayer, InspectorLayerInvalidationTrackingEvent::ReflectionLayerChanged);
layersNeedingPaintInvalidation.append(reflectionLayer);
m_layersChanged = true;
m_compositor->allocateOrClearCompositedDeprecatedPaintLayerMapping(reflectionLayer, compositedLayerUpdate);
}
m_compositor->updateDirectCompositingReasons(reflectionLayer);
// FIXME: Why do we updateGraphicsLayerConfiguration here instead of in the GraphicsLayerUpdater?
if (reflectionLayer->hasCompositedDeprecatedPaintLayerMapping())
reflectionLayer->compositedDeprecatedPaintLayerMapping()->updateGraphicsLayerConfiguration();
}
