Re: [css3-transitions] supporting 'transition-delay' on non-animatable properties?

On Nov 28, 2009, at 10:04 AM, L. David Baron wrote:

> Currently
> http://www.w3.org/TR/css3-transitions/#animation-of-property-types-
> has a special case for the animation of 'visibility' to allow
> authors to perform certain special effects, such as hiding elements
> at a certain time after a transition starts.
> 
> In https://bugzilla.mozilla.org/show_bug.cgi?id=521890#c4 Justin
> Dolske (who was converting the animations in our videocontrols for
> HTML5 video to transitions) suggested that perhaps
> 'transition-delay' could apply to all properties, not only those
> that are animatable.
> 
> This would be relatively straightforward for us to implement, and
> would give authors significantly more flexibility in handling
> transitions of non-animatable properties that they want to happen at
> the end of a transition of animatable properties.  (And, in
> particular, they could use 'display', which often has better
> performance characteristics when large amounts of content are
> hidden.)
> 
> If we did this, though, we may (or may not) want to remove the
> exception for visibility.  Removing the exception would require
> adding a transition-delay for visibility using the trick for getting
> reversing transitions, e.g.:
>  p { visibility: hidden; }
>  p.shown { visibility: visibile; }
>  p.shown { transition: visibility 0 1s; } /* not specified for p */
> which would likely make the 'transition' property more complicated
> when combined with other properties.

You'd have to do the same thing with 'display' too.

In general this seems like a useful thing to do, but I think we'd
need to implement it and play around for a while to see if it
makes sense.

Simon

Received on Wednesday, 2 December 2009 03:30:40 UTC