- 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