'Begin automatically stepping frames forward at the given rate (in fps).
This can also be accessed by pressing the spacebar.'

def play(self, rate):

    self.playRate = rate
    if (rate == 0):
        self.playTimer.stop()
        return
    self.lastPlayTime = ptime.time()
    if (not self.playTimer.isActive()):
        self.playTimer.start(16)
