CompositingReasons CompositingLayerAssigner::getReasonsPreventingSquashing(const RenderLayer* layer, const CompositingLayerAssigner::SquashingState& squashingState)
{
if (!squashingState.haveAssignedBackingsToEntireSquashingLayerSubtree)
return CompositingReasonSquashingWouldBreakPaintOrder;
ASSERT(squashingState.hasMostRecentMapping);
const RenderLayer& squashingLayer = squashingState.mostRecentMapping->owningLayer();
// FIXME: this special case for video exists only to deal with corner cases
// where a RenderVideo does not report that it needs to be directly composited.
// Video does not currently support sharing a backing, but this could be
// generalized in the future. The following layout tests fail if we permit the
// video to share a backing with other layers.
//
// compositing/video/video-controls-layer-creation.html
if (layer->renderer()->isVideo() || squashingLayer.renderer()->isVideo())
return CompositingReasonSquashingVideoIsDisallowed;
// Don't squash iframes, frames or plugins.
// FIXME: this is only necessary because there is frame code that assumes that composited frames are not squashed.
if (layer->renderer()->isRenderPart() || squashingLayer.renderer()->isRenderPart())
return CompositingReasonSquashingRenderPartIsDisallowed;
if (layer->reflectionInfo())
return CompositingReasonSquashingReflectionIsDisallowed;
if (squashingWouldExceedSparsityTolerance(layer, squashingState))
return CompositingReasonSquashingSparsityExceeded;
if (layer->renderer()->hasBlendMode())
return CompositingReasonSquashingBlendingIsDisallowed;
// FIXME: this is not efficient, since it walks up the tree. We should store these values on the CompositingInputsCache.
if (layer->clippingContainer() != squashingLayer.clippingContainer() && !squashingLayer.compositedLayerMapping()->containingSquashedLayer(layer->clippingContainer(), squashingState.nextSquashedLayerIndex))
return CompositingReasonSquashingClippingContainerMismatch;
// Composited descendants need to be clipped by a child containment graphics layer, which would not be available if the layer is
// squashed (and therefore has no CLM nor a child containment graphics layer).
if (m_compositor->clipsCompositingDescendants(layer))
return CompositingReasonSquashedLayerClipsCompositingDescendants;
if (layer->scrollsWithRespectTo(&squashingLayer))
return CompositingReasonScrollsWithRespectToSquashingLayer;
const RenderLayer::AncestorDependentCompositingInputs& compositingInputs = layer->ancestorDependentCompositingInputs();
const RenderLayer::AncestorDependentCompositingInputs& squashingLayerCompositingInputs = squashingLayer.ancestorDependentCompositingInputs();
if (compositingInputs.opacityAncestor != squashingLayerCompositingInputs.opacityAncestor)
return CompositingReasonSquashingOpacityAncestorMismatch;
if (compositingInputs.transformAncestor != squashingLayerCompositingInputs.transformAncestor)
return CompositingReasonSquashingTransformAncestorMismatch;
if (layer->hasFilter() || compositingInputs.filterAncestor != squashingLayerCompositingInputs.filterAncestor)
return CompositingReasonSquashingFilterMismatch;
return CompositingReasonNone;
}
bool CompositingLayerAssigner::canSquashIntoCurrentSquashingOwner(const RenderLayer* layer, const CompositingLayerAssigner::SquashingState& squashingState)
{
if (!squashingState.haveAssignedBackingsToEntireSquashingLayerSubtree)
return false;
// FIXME: this special case for video exists only to deal with corner cases
// where a RenderVideo does not report that it needs to be directly composited.
// Video does not currently support sharing a backing, but this could be
// generalized in the future. The following layout tests fail if we permit the
// video to share a backing with other layers.
//
// compositing/video/video-controls-layer-creation.html
// virtual/softwarecompositing/video/video-controls-layer-creation.html
if (layer->renderer()->isVideo())
return false;
if (squashingWouldExceedSparsityTolerance(layer, squashingState))
return false;
// FIXME: this is not efficient, since it walks up the tree . We should store these values on the AncestorDependentPropertiesCache.
ASSERT(squashingState.hasMostRecentMapping);
const RenderLayer& squashingLayer = squashingState.mostRecentMapping->owningLayer();
if (layer->renderer()->clippingContainer() != squashingLayer.renderer()->clippingContainer()) {
if (!squashingLayer.compositedLayerMapping()->containingSquashedLayer(layer->renderer()->clippingContainer()))
return false;
}
// Composited descendants need to be clipped by a child contianment graphics layer, which would not be available if the layer is
if (m_compositor->clipsCompositingDescendants(layer))
return false;
if (layer->scrollsWithRespectTo(&squashingLayer))
return false;
const RenderLayer::AncestorDependentProperties& ancestorDependentProperties = layer->ancestorDependentProperties();
const RenderLayer::AncestorDependentProperties& squashingLayerAncestorDependentProperties = squashingLayer.ancestorDependentProperties();
if (ancestorDependentProperties.opacityAncestor != squashingLayerAncestorDependentProperties.opacityAncestor)
return false;
if (ancestorDependentProperties.transformAncestor != squashingLayerAncestorDependentProperties.transformAncestor)
return false;
if (ancestorDependentProperties.filterAncestor != squashingLayerAncestorDependentProperties.filterAncestor)
return false;
return true;
}