unsigned width = update_rect.right-update_rect.left;
unsigned height = update_rect.bottom-update_rect.top;
signal_expose.emit(update_rect.left, update_rect.top, width, height, evnt);
unsigned width = update_rect.right-update_rect.left;
unsigned height = update_rect.bottom-update_rect.top;
signal_expose.emit(update_rect.left, update_rect.top, width, height, evnt);