BottomChild
startFrom? startFrom: BottomChild());
for (Layer *lay = BottomChild(); lay; lay = UpperSibling())
for (Layer *lay = BottomChild(); lay; lay = UpperSibling()) {
for (Layer *lay = BottomChild(); lay; lay = UpperSibling()) {
for (Layer *lay = BottomChild(); lay; lay = UpperSibling())
rebuild_visible_regions(invalid, invalid, BottomChild());
for (Layer *lay = BottomChild(); lay; lay = UpperSibling()) {
lay->rebuild_visible_regions(invalid, common, lay->BottomChild());
for (Layer *child = BottomChild(); child; child = UpperSibling())
for (Layer *child = BottomChild(); child; child = UpperSibling())
Layer* BottomChild() const;
for (Layer *child = lay->BottomChild(); child; child = lay->UpperSibling())
for (Layer *child = lay->BottomChild(); child; child = lay->UpperSibling())