'draw using newfangled blit or oldfangled draw depending on
useblit'

def update(self):

    if (not self.ax.get_visible()):
        return False
    if self.useblit:
        if (self.background is not None):
            self.canvas.restore_region(self.background)
        for artist in self.artists:
            self.ax.draw_artist(artist)
        self.canvas.blit(self.ax.bbox)
    else:
        self.canvas.draw_idle()
    return False
