void fill_rectangle(int left, int top, int right, int bottom,
const Brush &brush) {
if (brush.is_hollow())
return;
fill_rectangle(left, top, right, bottom, brush.get_color());
}
/**
* Returns true if the outline should be drawn after the area has
* been filled. As an optimization, this function returns false if
* brush and pen share the same color.
*/
bool pen_over_brush() const {
return pen.defined() &&
(brush.is_hollow() || brush.get_color() != pen.get_color());
}