static Layer*
FindBackgroundLayer(ReadbackLayer* aLayer, nsIntPoint* aOffset)
{
gfx::Matrix transform;
if (!aLayer->GetTransform().Is2D(&transform) ||
transform.HasNonIntegerTranslation())
return nullptr;
nsIntPoint transformOffset(int32_t(transform._31), int32_t(transform._32));
for (Layer* l = aLayer->GetPrevSibling(); l; l = l->GetPrevSibling()) {
gfx::Matrix backgroundTransform;
if (!l->GetTransform().Is2D(&backgroundTransform) ||
gfx::ThebesMatrix(backgroundTransform).HasNonIntegerTranslation())
return nullptr;
nsIntPoint backgroundOffset(int32_t(backgroundTransform._31), int32_t(backgroundTransform._32));
nsIntRect rectInBackground(transformOffset - backgroundOffset, aLayer->GetSize());
const nsIntRegion& visibleRegion = l->GetEffectiveVisibleRegion();
if (!visibleRegion.Intersects(rectInBackground))
continue;
// Since l is present in the background, from here on we either choose l
// or nothing.
if (!visibleRegion.Contains(rectInBackground))
return nullptr;
if (l->GetEffectiveOpacity() != 1.0 ||
!(l->GetContentFlags() & Layer::CONTENT_OPAQUE))
return nullptr;
// cliprects are post-transform
const nsIntRect* clipRect = l->GetEffectiveClipRect();
if (clipRect && !clipRect->Contains(nsIntRect(transformOffset, aLayer->GetSize())))
return nullptr;
Layer::LayerType type = l->GetType();
if (type != Layer::TYPE_COLOR && type != Layer::TYPE_THEBES)
return nullptr;
*aOffset = backgroundOffset - transformOffset;
return l;
}
return nullptr;
}
bool
BasicContainerLayer::ChildrenPartitionVisibleRegion(const gfx::IntRect& aInRect)
{
Matrix transform;
if (!GetEffectiveTransform().CanDraw2D(&transform) ||
ThebesMatrix(transform).HasNonIntegerTranslation())
return false;
nsIntPoint offset(int32_t(transform._31), int32_t(transform._32));
gfx::IntRect rect = aInRect.Intersect(GetEffectiveVisibleRegion().GetBounds() + offset);
nsIntRegion covered;
for (Layer* l = mFirstChild; l; l = l->GetNextSibling()) {
if (ToData(l)->IsHidden())
continue;
Matrix childTransform;
if (!l->GetEffectiveTransform().CanDraw2D(&childTransform) ||
ThebesMatrix(childTransform).HasNonIntegerTranslation() ||
l->GetEffectiveOpacity() != 1.0)
return false;
nsIntRegion childRegion = l->GetEffectiveVisibleRegion();
childRegion.MoveBy(int32_t(childTransform._31), int32_t(childTransform._32));
childRegion.And(childRegion, rect);
if (l->GetClipRect()) {
childRegion.And(childRegion, ParentLayerIntRect::ToUntyped(*l->GetClipRect()) + offset);
}
nsIntRegion intersection;
intersection.And(covered, childRegion);
if (!intersection.IsEmpty())
return false;
covered.Or(covered, childRegion);
}
return covered.Contains(rect);
}
