[web-anim] Web animations minutes, 3 / 4 December 2012

Web animations minutes, 3 / 4 December 2012

Etherpad: https://etherpad.mozilla.org/ep/pad/view/ro.TRxQaiTHpEH/latest
Present: Dmitry Baranovskiy, Steve Block, Shane Stephens, Douglas 
Stockwell, Brian Birtles

Agenda:

1. Status update
2. Where to from here
3. Animation groups
4. Animation timelines / triggers
5. Animation stack & Keyframe animations

1. STATUS UPDATE
================

Brian:
* Lots of renaming stuff
* Tweaks to make zero-duration animations easier to create
* Removed TimingFuncCallback

Shane, Steve, Doug:
* Polyfill implementation work

2. WHERE TO FROM HERE
======================
(Shane)

➙ Agreed we want to prioritise the CSS and SVG integration work

* Discussed briefly the importance of templates
➙ Agreed we can possibly drop them from v1 but will consider further

Can we make the ED more of a "living spec"? Include some v2 features 
that are clearly marked / filtered out of the FPWD version.

• Some discussion about the value of keeping a single living spec from 
which we publish different versions vs having a v1 spec plus an extra 
dumping ground for v2 features and annotations in the v1 spec indicating 
how those features will be integrated
• Needs some more consideration

FPWD - when? Can we use the FXTF telecon times to start working towards it?
   • Work as if we're going to be FPWD-ready by end 2012, but 
realistically as long as we have it in time for the CSS and SVG F2F in 
Feb we should be ok
   • Wait until FPWD-ready before using FXTF times
F2F in Sydney after SVGWG meeting?
   • Yes, sometime in the week of 11 Feb 2013
Browser Miniconf @ LCA (end of Jan)
   • Shane hopes to present about Web Animations

3. ANIMATION GROUPS
===================
(Shane)

I  mentioned last meeting that there were some problems with grouping 
and merging of animation effects. I have a solution which basically 
involves automatically grouping within containers. There's a doc here 
describing  the problem, some solution approaches, and my preferred 
approach: 
http://www.w3.org/Graphics/fx/wiki/Web_Animations/Issues/Grouping_of_Animations

Brian:  I had a look. I like the parameterisation of merge. I wonder why 
merge  has to use the parent container's duration. Given recent pushback 
  regarding Web Anim's apparent complexity, I wonder how critical 
merging  is for v1.

➙ Discussed possibility of dropping merging from v1. The difficulty is 
that to-animation is essentially a merge. Discussed the possibility of 
still implementing to-animation as a merge but not exposing merging in 
general through the API in v1.

➙ We will resume further discussion of merging at our next F2F

4. ANIMATION TIMELINES / TRIGGERS
===============================
(Shane)

➙ Everyone to read through both (a) Shane’s notes about time sources and 
triggers and (b) Brian’s notes below about Integration with Media for 
discussion on Friday
(a) 
https://docs.google.com/document/d/1F2-v4D6n0RBBTc4m5zLL0oUV4HHPIE4myarKey6nC8k/edit
(b) https://etherpad.mozilla.org/MzLg1iUKv4 point 3, 'Integration with 
media'

5. ANIMATION STACK & KEYFRAME ANIMATIONS
========================================
(Shane)

Keyframe  animations rely on a "base value" when no initial or no final 
keyframe is specified. Problem is this isn't defined anywhere:
http://dvcs.w3.org/hg/FXTF/raw-file/tip/web-anim/index.html#calculating-the-iteration-value-for-a--------------keyframeanimfunc

The intention is to be able to use a "replace" animation with a single 
keyframe for an SVG-style "to" animation. But this breaks the intention 
of "replace" quite a bit (it should completely ignore everything 
underneath it). So we could:
a) sample the style when a one-keyframe animation is _created_ and use 
for the base value
b) sample the underlying style on each frame for one-keyframe 
animations, and use this for the base value
c)  instead use "merge" animations with a constant destination value for 
an  SVG-style "to" animation (and reverse this / augment merge slightly 
to  support "from" animations)

-> SVG "to" animations will become merge:
<animate to="100px" attributeName="length"> → new Anim(..., {length: 
["100px", "100px"], operation: "merge"}, ...)

-> CSS keyframe parsing
omitted 0% and 100% values are snapshotted at parse time.

-> new Anim(..., {length: "100px"}, ...)
should turn into {length: ["100px", "100px"], operation: "merge"}

-> new Anim(..., {length: ["100px"]}, ...)
should turn into {length: ["0px", "100px"], operation: "replace"}

➙ We generally like the merge approach for to animations but, what is 
intuitive when you have keyframes that don’t cover the entire span from 
0% to 100% is not yet clear.

➙ Shane to put together some ideas for what to do when there is no 
keyframe covering a given time.
  - Raphaël starts from the base value and finishes at the last keyframe


Next meeting: Thurs Dec 6, 17:30 PST / Fri 7 Dec 12:30 AEDST  / Fri 7 
Dec 10:30 JST @ https://etherpad.mozilla.org/MzLg1iUKv4

Past meetings: http://www.w3.org/Graphics/fx/wiki/Web_Animations/Meetings

Received on Tuesday, 4 December 2012 05:00:53 UTC