W3C home > Mailing lists > Public > www-style@w3.org > February 2012

[css3-transitions] proposed issues for resolution/discussion

From: L. David Baron <dbaron@dbaron.org>
Date: Tue, 21 Feb 2012 12:19:31 -0800
To: www-style@w3.org
Message-ID: <20120221201931.GA23436@pickering.dbaron.org>
I've been going through the css3-transitions issues in Bugzilla:
https://www.w3.org/Bugs/Public/buglist.cgi?query_format=advanced&product=CSS&component=Transitions&resolution=---&cmdtype=doit
in particular, with an eye towards categorizing them as
easy/medium/hard to resolve and also towards grouping them.  I
haven't yet gone through all of them, but I think I've gone through
enough that it may be worth spending time on them in a
teleconference.

Accordingly, I'd like to propose that we take the resolutions below
on postponing and the "easy" issues and discuss the "medium" issues
at an upcoming teleconference.

Things to postpone
==================

Postpone animation of images and gradients to css4-images (including
removing the prose currently in the spec about gradients), to
address:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14610
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14612
https://www.w3.org/Bugs/Public/show_bug.cgi?id=16024

Postpone having transitions apply to non-interpolable value types to
the next level of transitions:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14609

Postpone having animation rules for 'display' (perhaps a subset of
the previous):
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14614

Postpone the addition of an API to force a transition to start to
the next level of transitions:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14617

Postpone rules for animation of shadows from inset to outset
(probably to css4-background):
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14716

Postpone rules for animation to/from auto values (if we want to do
this at all):
https://www.w3.org/Bugs/Public/show_bug.cgi?id=15844

Has a clear proposed solution ("easy")
======================================

Resolve that it's the length of the transition-property list that
matters, and the computed values of the other properties are
repeated or truncated as needed (just like background-image):
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14604

Resolve that we'll postpone adding a feature for easily doing the
reverse animation differently (or symmetrically), but give an
example of how to do it using the current spec (i.e., an example of
what happens when transition-timing-function is specified
differently for :hover), given that it's a common request:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14611

Resolve to remove mention of the 'grid' and 'zoom'
properties/non-properties from the spec:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14618
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14626

Resolve that 'vertical-align' keywords aren't animatable:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14988

Resolve that no transition occurs when transition-duration and
transition-delay are both 0s:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=15838

Have a good chance of being settled after brief discussion ("medium")
=====================================================================

We should discuss the rules for interpolating 'font-weight':
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14613
Gecko's behavior is to interpolate numerically and then round to the
nearest multiple of 100 (clamping to 100-900).  I'm happy to resolve
to specify this, but I'm not sure what others do.

We should discuss the rules for transitioning 'visibility'.  The
spec is clear on what to do for transitions between visible and
hidden, but it's not clear what we should do for transitions
involving 'collapse'.  Should they be non-interpolable or should
there be an interpolation rule?
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14619

We should discuss whether events fire for transitions on
pseudo-elements:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=15847

Probably requires some more mailing list discussion or a proposal ("hard")
==========================================================================

Rules for interpolation of transforms
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14608

Rules for handling value changes in the middle of a transition
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14615

Rules for interpolation of multiple backgrounds
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14621

Fixing the definition of when transitions are triggered to account
for cases like animation of font-size with relative lengths on other
properties
https://www.w3.org/Bugs/Public/show_bug.cgi?id=14723

-David

-- 
𝄞   L. David Baron                         http://dbaron.org/   𝄂
𝄢   Mozilla                           http://www.mozilla.org/   𝄂
Received on Tuesday, 21 February 2012 20:19:57 GMT

This archive was generated by hypermail 2.3.1 : Tuesday, 26 March 2013 17:20:50 GMT