Re: [css3-animations] Effect of display:none and visibility:hidden on animations

On 01/08/2011, at 2:25 PM, Jonathan Snook wrote:

>> The spec should say that non-animatable properties in a keyframe value rule are applied (we agreed for transitions that non-animatable properties do actually change over time, at the end of the duration). If that's not the case then I'll fix it. If WebKit doesn't implement this then it's a bug too.
> 
> The current spec says, "Properties that are unable to be animated are ignored in these rules", in Keyframes.
> http://www.w3.org/TR/css3-animations/#keyframes- 
> 

Right. The CSS WG resolved that non-animatable properties would still undergo transitions. eg. they change after some transition-delay + duration period. You can use the steps timing function to control if it should happen at the start or end of duration.

The group didn't talk about animations, but I expect they will agree that the same should apply. If not, hopefully they will speak up now.

My one concern is the fact that the spec doesn't really say much about exactly when the animation starts. If your non-animated style is display:none, but your animated style is display:block, we don't want to tear down the rendertree and then build it again immediately. That's a spec concern that shouldn't bother developers.

> If you fixed this, this would be excellent. Webkit more accurately reflects the spec as-is (ie: non-animatable properties are ignored) but would love to file a bug for such (ie: non-animatable properties should be applied, just not animated).

I just filed two:

https://bugs.webkit.org/show_bug.cgi?id=65488
https://bugs.webkit.org/show_bug.cgi?id=65489

One is for animations, the other for transitions (WebKit code treats them slightly differently in this case). I encourage someone to file similar bugs on Mozilla + Opera + IE + whatever.

Dean