- From: Brian Birtles <birtles@gmail.com>
- Date: Wed, 01 Aug 2012 08:09:10 +0900
- To: www-style@w3.org
Hi Julien,
I should point out that many of these use cases are being considered in
the Web Animations specification.[1] In particular, putting animations
on a timeline that can be seeked is covered there.
The section on synchronising animations with video has yet to be written
up but some notes are available.[2] In short, we are looking at re-using
the HTML5 media group facility by exposing a media-group CSS property.
Thanks,
Brian
[1] https://dvcs.w3.org/hg/FXTF/raw-file/tip/web-anim/index.html
[2] https://etherpad.mozilla.org/lIwpKlVNd2, section 4
(2012/08/01 7:42), Julien Dorra wrote:
> François, nice example. It would really bring a new aspect to animations
> in CSS. I would use it myself :-)
>
> If I skip right in the middle of an animation, clicking on the timeline,
> the browser would have - as you noted - to render the animation(s) state
> at that point.
>
> Is there someone that can tell us how complicated in term of
> implementation that would be?
> (btw, is display animable at the moment?)
>
> Very stimulating discussion, here. There *is* a need for synchronization
> with media elements, and having different ways to do might be a good
> thing. Popcorn and Instapoppin are covering the JS side (using JSON or
> data- attribute), but having the sync information in a standardized
> format would be great for the longterm.
>
> comprehensive example of what it could look like:
>
> *HTML:*
> <div class=”my-video-overlay” style=”animation-delay: 0s;
> animation-duration: 15s;”>...</div>
> <div class=”my-video-overlay” style=”animation-delay: 543s;
> animation-duration: 15s;”>...</div>
> <video id=”my-video”>...</video>
>
> *CSS:*
> .my-video-overlay {
> display: none; animation-name: show;
> animation-time-source: url(#my-video);
> ... position ...
> }
>
> @keyframes show {
> from { opacity: 0; display: block; }
> 10 % { opacity: 1; }
> 90 % { opacity: 1; }
> to { opacity: 0; display: none; }
> }
>
> During the 15 first seconds of the video, the first overlay would be
> displayed and would be hidden after that. During the 15 last
> seconds, the second overlay would. If the user rewinds back in time
> or skip to another location of the video, the time would rewind at
> the same pace as the video, keeping them always in sync.
> From an implementation perspective, the only difference is that the
> time used in the easing functions is not the system time but the
> time defined by a video element. Also, it’s possible to go back in
> time so that may have an effect on implementations.
>
>
Received on Tuesday, 31 July 2012 23:09:43 UTC