/**
* Returns a rectangle of content painted opaquely by aLayer. Very consertative;
* bails by returning an empty rect in any tricky situations.
*/
static nsIntRect
GetOpaqueRect(Layer* aLayer)
{
nsIntRect result;
// Just bail if there's anything difficult to handle.
if (!aLayer->GetEffectiveTransform().IsIdentity() ||
aLayer->GetEffectiveOpacity() != 1.0f ||
aLayer->GetMaskLayer()) {
return result;
}
if (aLayer->GetContentFlags() & Layer::CONTENT_OPAQUE) {
result = aLayer->GetEffectiveVisibleRegion().GetLargestRectangle();
} else {
// Drill down into RefLayers because that's what we particularly care about;
// layer construction for aLayer will not have known about the opaqueness
// of any RefLayer subtrees.
RefLayer* refLayer = aLayer->AsRefLayer();
if (refLayer && refLayer->GetFirstChild()) {
result = GetOpaqueRect(refLayer->GetFirstChild());
}
}
const nsIntRect* clipRect = aLayer->GetEffectiveClipRect();
if (clipRect) {
result.IntersectRect(result, *clipRect);
}
return result;
}
/**
* Returns a rectangle of content painted opaquely by aLayer. Very consertative;
* bails by returning an empty rect in any tricky situations.
*/
static nsIntRect
GetOpaqueRect(Layer* aLayer)
{
nsIntRect result;
gfx::Matrix matrix;
bool is2D = aLayer->GetBaseTransform().Is2D(&matrix);
// Just bail if there's anything difficult to handle.
if (!is2D || aLayer->GetMaskLayer() ||
aLayer->GetEffectiveOpacity() != 1.0f ||
matrix.HasNonIntegerTranslation()) {
return result;
}
if (aLayer->GetContentFlags() & Layer::CONTENT_OPAQUE) {
result = aLayer->GetEffectiveVisibleRegion().GetLargestRectangle();
} else {
// Drill down into RefLayers because that's what we particularly care about;
// layer construction for aLayer will not have known about the opaqueness
// of any RefLayer subtrees.
RefLayer* refLayer = aLayer->AsRefLayer();
if (refLayer && refLayer->GetFirstChild()) {
result = GetOpaqueRect(refLayer->GetFirstChild());
}
}
// Translate our opaque region to cover the child
gfx::Point point = matrix.GetTranslation();
result.MoveBy(static_cast<int>(point.x), static_cast<int>(point.y));
const nsIntRect* clipRect = aLayer->GetEffectiveClipRect();
if (clipRect) {
result.IntersectRect(result, *clipRect);
}
return result;
}
