Add a "paused" state to timing objects?

[tidoust]

Media elements in HTML5 have a paused flag that is different from setting the playbackRate to 0.0. It might be useful to introduce the same concept for TimingObject.

From a spec perspective, this woud likely mean to introduce this flag in the definition of the TimingStateVector interface.

That does not strike me as a top priority at this stage, just raising the issue to keep track of it.

[ingararntzen]

The difference as I have understood it is that the paused flag can be trusted to represent the true state of the media player, whereas the playbackRate is a specification of default playback velocity, a value which will survive pause/resume toggling. If this is correct then I think the timing object API can easily be extended to support this (by the programmer on demand).

For example, something like this should work?

var defaultPlaybackRate = 1.0;
to.__defineGetter__("playbackRate", function () {return defaultPlaybackRate;});
to.__defineSetter__("playbackRate", function (value) {defaultPlaybackRate = value;})

to.__defineGetter__("paused", function () {
    var vector = to.query();
    return (vector.velocity === 0.0 && vector.acceleration === 0.0);
});
to.__defineSetter__("paused", function (value) {
    // pause
    if (value) to.update(null, 0.0, 0.0);
    // resume
    else to.update(null, to.playbackRate, null);
});

[Snarkdoof]

Having programmers solve this programmatically makes it single device by nature though, as one device pausing and another (newly joined) unpausing will not know what the speed was. Not a very likely problem I guess, and it adds an unnecessary complication to the very nice vector and clean motion vector. I would very much like feedback from others on this too.