progress question about duration 0 tweens

[erikb 29 Likes (Newbie)]

In my example, shouldn't progress in an onUpdate callback for a 0 duration tween return 1?

See the Pen mHvFj by jedierikb (@jedierikb) on CodePen

Edited June 3, 2015 by erikb

[GreenSock 18,597 Likes (Superhero)]

Zero-duration tweens are an odd concept because they're not really tweens at all. And when the playhead lands directly on top of one, should that be interpreted as its "beginning" or "end" (there isn't really such a thing when there's no duration). See what I mean? We have done a lot of work to accommodate them, though, mostly by looking at the direction of the playhead as well as a few other factors, so they should behave in an intuitive way. 

 

I've never seen someone try what you're doing before, but I've added some code to resolve that in the next release. No problem. For now, you can simply check the tween's "ratio" instead (it'll be 1 at the end of a 0-duration tween, and 0 at the beginning). Keep in mind that the ratio is a number that's affected by the easing; it's not linear like progress is. 

[sitherikb 0 Likes (Newbie)]

Thanks!  I've many tweens where sometimes they have >0 durations, but sometimes they have to just jump to their destinations.  

 

I could check for duration before tweening and call set or to depending.  But it feels cleaner to just use duration 0.

[GreenSock 18,597 Likes (Superhero)]

Oh, it's fine to use a duration of 0 in a to() instead of set() - the result is exactly the same thing. A set() is just a zero-duration to() call internally anyway.