[CSS-animations] animation-fill-mode on partial iteration

The spec and implementation are different when it comes to handling animation-fill-mode on a partial animation cycle.

Safari follows the spec.
The implementation of FF and Blink do not follow the spec, but make more sense.
Haven't tried IE. 

Example is at http://estelle.github.io/animation/files/halfiterationforwards.html.
Spec is at: http://dev.w3.org/csswg/css-animations/#animation-timing-function where it reads:

Note: If animation-iteration-count is a non-integer value, the animation will stop executing partway through its animation cycle, but a forwards fill will still apply the values of the 100% keyframe, not whatever values were being applied at the time the animation stopped executing.

Basically the spec says now "no matter where you are in the animation, jump to the 100% keyframe" which is what safari does. FF and Blink stay on the keyfraome where the partial animation ended.

Safari goes to the 100% keyframe even if the last iteration is 'reverse', which seemingly conforms to the spec, but truly doesn't look right if you were on the 99% keyframe.

Is the spec going to change to reflect blink's and FF's behavior? Or should i file a bug with chrome and FF? I am hoping the spec changes.

Estelle Weyl
estelle@weyl.org
http://www.standardista.com

Received on Friday, 3 October 2014 22:07:06 UTC