PIXI.ticker - DeltaTime vs elapsedMS

[Gerente]

What is the difference between PIXI.ticker.shared.elapsedMS and  the deltaTime in 

ticker.add(function (deltaTime) {
    renderer.render(stage);
});

The elapsedMS  returns 6.94444444444

the deltaTime returns 0.416666666

 

I don't see the relation.

 

Thanks

 

[ivan.popelyshev]

Consier we have 60FPS and everything is fine, then deltaTime=1. If we have lags and 30FPS as result, in that case deltaTime is 2.

If you want to move the object 5 pixels per frame, then use "5 * deltaTime"

[Gerente]

Thanks, I understand that, but shouldnt elapsedMS  do the same thing?

[ivan.popelyshev]

Its the same thing, but in milliseconds. If you want "300 pixels per second" you use "0.3 * elapsedMs" , and if you want "5 pixels per frame" you use "5 * deltaTime"

[PsichiX]

not 5 pixels per frame (that way it would be just 5)

[ivan.popelyshev]

35 minutes ago, PsichiX said:

not 5 pixels per frame (that way it would be just 5)

That's why its useful - if you dont know how to make animation smooth - just multiply whatever you want by deltaTime.

[Gerente]

please read my post, they have different values. maybe there is a bug. Mostly when I'm in another tab and then I come back

[ivan.popelyshev]

> Mostly when I'm in another tab and then I come back

Not a bug.

Read the ticker sources: https://github.com/pixijs/pixi.js/blob/dev/src/core/ticker/Ticker.js#L40

> The elapsedMS  returns 6.94444444444

> the deltaTime returns 0.416666666

0.42 = 7 * 60 / 1000

[Gerente]

Ooooh, that's why, elapsedMS is in seconds (even if the name says MS) and deltaTime in miliseconds.

As always, thanks IVAN!

[ivan.popelyshev]

its in milliseconds. deltaTime is in frames, if you want TARGET_FPMS. By default its 1/60 of second.