Negative lastTicksElapsed after Pause/Resume

[Dana Powers]

Is it expected behavior for ticker.lastTicksElapsed to turn negative after a pause and resume? start and currentTick are reset, but later, in the next() function, _saved is added back to currentTick. This causes lastTicksElapsed to run negative because currentTick [big number] is subtracted from ticksElapsed [small number] in each un-paused run() loop.

current code:

_Ticker.prototype.resume = function() {
// useful to keep the accurate number of ticks after resume
this._saved += ((this.now - this.start) / this.tickDuration) | 0
this.start = new Date().getTime();
this.ticksElapsed = 0;
this.currentTick = 0;
this.paused = false;
this.run();
}

_Ticker.prototype.next = function() {
// number of ticks that have happen tile the last pause
var ticksElapsed = ((this.now - this.start) / this.tickDuration) | 0;
this.lastTicksElapsed = ticksElapsed - this.currentTick;
this.currentTick = ticksElapsed + this._saved;
return this.lastTicksElapsed;
};

I'm not sure what the purpose of "this.currentTick = ticksElapsed + this._saved;" is (why is it useful to keep the accurate number of ticks after resume?), but commenting it out fixes this problem.

[Batiste Bieler]

Hi,

You are right there was an issue there. The idea is that currentTick should remain accurate if you use it as a basis for physic and animation. The changes I made in the following commit should retain this characteristic without the negative value weirdness:

2974471

Is it fixed for you?

[Dana Powers]

Yes - that fixes the problem for me. Thanks!

On Thu, Sep 8, 2011 at 3:12 AM, Batiste Bieler
[e-mail]
wrote:

Hi,

You are right there was an issue there. The idea is that currentTick should remain accurate if you use it as a basis for physic and animation. The changes I made in the following commit should retain this characteristic without the negative value weirdness:

2974471

Is it fixed for you?

Reply to this email directly or view it on GitHub:
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