Object for keeping track of time. This uses [link:https://developer.mozilla.org/en-US/docs/Web/API/Performance/now performance.now] if it is available, otherwise it reverts to the less accurate [link:https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Date/now Date.now].
autoStart — (optional) whether to automatically start the clock. Default is true.
If set, starts the clock automatically when the first update is called. Default is true.
Holds the time at which the clock's [page:Clock.start start] method was last called.
Holds the time at which the clock's [page:Clock.start start], [page:Clock.getElapsedTime getElapsedTime] or [page:Clock.getDelta getDelta] methods were last called.
Keeps track of the total time that the clock has been running.
Whether the clock is running or not.
Starts clock. Also sets the [page:Clock.startTime startTime] and [page:Clock.oldTime oldTime] to the current time, sets [page:Clock.elapsedTime elapsedTime] to *0* and [page:Clock.running running] to *true*.
Stops clock and sets [page:Clock.oldTime oldTime] to the current time.
Get the seconds passed since the clock started and sets [page:Clock.oldTime oldTime] to the current time.
If [page:Clock.autoStart autoStart] is *true* and the clock is not running, also starts the clock.
Get the seconds passed since the time [page:Clock.oldTime oldTime] was set and sets [page:Clock.oldTime oldTime] to the current time.
If [page:Clock.autoStart autoStart] is *true* and the clock is not running, also starts the clock.
[link:https://github.com/mrdoob/three.js/blob/master/src/[path].js src/[path].js]