Re: [css-animations] How animation-timing-function in keyframe rule interacts with direction

On Thu, Oct 16, 2014 at 2:47 PM, Sylvain Galineau <galineau@adobe.com> wrote:
> We should resolve the issue raised by dbaron [1] (Bug 14805 [2])
>
> If we have:
>
>         @keyframes timings {
>                 25% { animation-timing-function: linear; }
>                 40% { animation-timing-function: ease-out; }
>         }
>
> ..then when the animation moves forward we expect linear to apply between 25% and 40%. But if the animation is moving backward e.g. due to an animation-direction: alternate then we also want linear to apply between 40% and 25%.
>
> Objections?

No, that's clearly what you want.  (And between 100% and 40%, you want
to run ease-out in reverse.)

There is no way to defend any other answer.  We attach a timing
function to a given keyframe for reasons of *syntax*; we're actually
defining a timing function over an interval.

~TJ

Received on Thursday, 16 October 2014 22:25:03 UTC