void clear()
{
absoluteTransforms.resize(1);
// Important!! Due to all the swapping, the first entry in the list is not necessarily
// the base matrix. We need to restore it.
absoluteTransforms.front() = scale(1);
individualTransforms.resize(1);
clipRectStack.clear();
glBlocks.clear();
ops.clear();
}
// This retains the current stack of transforms and clippings.
void clearQueue()
{
glBlocks.clear();
ops.clear();
}
