'Blit the region in bbox.'

def blit(self, bbox=None):

    if ((bbox is None) and self.figure):
        bbox = self.figure.bbox
    self._bbox_queue.append(bbox)
    (l, b, w, h) = [(pt / self._dpi_ratio) for pt in bbox.bounds]
    t = (b + h)
    self.repaint(l, ((self.renderer.height / self._dpi_ratio) - t), w, h)
