Constants used by
Clock#tick to determine behavior
when Clock#startTime or Clock#stopTime is reached.
Members
When
Clock#startTime or Clock#stopTime is reached,
Clock#tick will not advance Clock#currentTime any further.
When
Clock#stopTime is reached, Clock#tick will advance
Clock#currentTime to the opposite end of the interval. When
time is moving backwards, Clock#tick will not advance past
Clock#startTime
Clock#tick will always advances the clock in its current direction.