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<trackbot> Date: 25 September 2014
<scribe> scribenick: birtles
<scribe> scribe: birtles
ChrisL: filters is obviously a
widely-deployed technology in all the browsers and
implementations
... so I expected the filters spec for CSS would be at a
similar level of maturity
... I was looking at the testsuite and it only has 30 something
tests
... presumably because they have to be reftests and have to be
a certain style
... so it's not many tests
... and when I ran through them in different browsers there
were so many failures
... it seemed like all failed in IE
... I was surprised to see that
... I wondered what's happenning, are the tests wrong? what's
up?
krit: many reference tests for
filter effects test filters in HTML
... and IE doesn't support filters in HTML
... also similar for WebKit
... and we added some new filter functions that are currently
only supported in WebKit and Blink and soon in Firefox
<heycam> http://status.modern.ie/filters "Under consideration" for IE
krit: you're right we don't have
a lot of tests yet
... my colleague has been working on that as part of
implementing in Firefox
... so hopefully those tests can be imported
... since they should be in the right format
ChrisL: is there a repository for that?
krit: it's in the Gecko
repository
... I can ask him to send the link
ChrisL: I know Opera released a
lot of tests
... I wonder if any of those cover filters
ed: there might be some filter tests for I don't think there would be any for CSS filters
ChrisL: I remember that Presto did filters in HTML right?
ed: no, only internal experiments
ChrisL: well, that explains
that
... Dirk you said there was something being working on?
... is this something we expect the browsers to do?
krit: there's active development
in Blink but not so much in WebKit right now (probably change
in the next few months)
... we want to have the same feature set
... but we are missing from the specification the order of the
regions
... I have no status report from Microsoft
... it is being worked on in Blink
... currently stagnating in WebKit
... hopefully enabled soon in Firefox
... already available in the Nightly versions
ChrisL: that's better than I feared but still
Tav: does the Firefox implementation handle shorthands?
krit: yes
Tav: how about webkit?
krit: just for HTML
ed: does the Firefox support shorthands for SVG too?
krit: yes
heycam: is that working now?
krit: yes, it works
ChrisL: I was only testing
Firefox beta so that would explain some test failures
... I will do another run-through with nightly
<heycam> layout.css.filters.enabled
krit: there might be a flag
<heycam> that is not enabled by default currently
ChrisL: do I have to enable any features on Chrome canary?
krit: it's enabled by default in
Chrome canary but kind of broken
... same for webkit
<heycam> https://bugzilla.mozilla.org/show_bug.cgi?id=869828 -- the meta bug for CSS Filters in Firefox
ChrisL: is there any specific
bugs I should track?
... should I report individual test failures on that bug? or a
new bug?
heycam: you can file a new bug and make it block this (the above) bug
ChrisL: the other question is,
how easy is it going to be to make tests for some of these
filter functions?
... like the turbulence filter
... especially if we're trying to make it produce a green
square
... maybe just a PNG image comparison
krit: yes, that's difficult
<ed> for blink: http://crbug.com/109224 (tagging bugreports with "Cr-Blink-CSS-Filters" is probably good, or ping me and I'll set that tag on the bugs)
krit: I think Firefox has reference tests, I'm not sure how they do that
heycam: I'm not sure we have
reference tests for turbulence
... but the firefox reftest system does allow you to specify
tolerance to account for anti-aliasing differences etc.
... but that might not be enough
ChrisL: so it seems like there
are a few outstanding spec issues
... might it go back to LC?
krit: it's currently WD
ChrisL: yes, you're right
... I just put out a new timeline for a our charter
... which is how I discovered that filters was less advanced
than I thought it would be
... Dirk, you said there was an issue about the order of filter
regions
krit: currently we have a hard
clipping region that is 10% around the object
... the proposal was to get rid of that and replace it with
auto-computation of the bounds of the filter
... and I'm working on that auto-computation
heycam: was there still and outstanding issue about the filter resolution
krit: we removed filterRes but we
still have the kernel units one
... but kernelUnitLength is needed
... it makes other parameters resolution-independent but they
don't look good
... so there's still an issue but I don't think we can fix it
with the current primitives we have
heycam: is it an issue of how the
filters are defined?
... working on physical pixels rather than logical pixels?
krit: right, they work on
physical pixels
... and if you make them work on logical pixels then you'd end
up with pixelation
heycam: so is the spec going to
stay as it is?
... were you planning on making any more changes to this part
of the spec?
krit: no
... the primitives that are affected by that are
feConvolveMatrix and fePointLight or one of the lighting
filters
ed: diffuse lighting I think
krit: oh yes, that's right
<ed> specularlighting too
heycam: do you need any help/planning with regards to the test suite
krit: help is always welcome
heycam: do you need it?
krit: the spec definitely needs
tests
... occasionally I try to write tests but the specification is
still much larger than the number of tests we have
... so if someone is willing, yes please
ChrisL: I'm willing to do it but I'm trying to work out to make them into suitable reftests
krit: it might be good to start
by looking at Firefox's reftests
... can Firefox use pixel tests?
heycam: you can always do that by putting a raster in the reference
krit: in WebKit and Blink we definitely use pixel tests because it's easier but it's not cross-browser
<heycam> https://github.com/mozilla/gecko-dev/tree/master/layout/reftests/svg/filters
heycam: some filters are easier
to test as reftests than others
... e.g. the color transform tests just do it on a solid color
fill
krit: but even that could differ on other implementations, by on RGB value
heycam: so you can't specify pixel tolerances for the web-platform-tests setup?
krit: you can exploit that pixels
have to be clamped to within [0..255]
... and produce a test that puts you in that range
ChrisL: I can see the advantage
of automated tests but it makes writing the tests hard
... and boring
Tav: I thought we agreed to have both (automated and manual)
krit: but then how do you deliver the tests?
heycam: we had that in the past, we asked people to eyeball the tests
ChrisL: web-platform-tests
doesn't allow multiple references like the CSS tests do
... it allows you to say it should match one or more
references
... I remember that when we first did filters there were a lot
of images exchanged and equations specced so that we had two
implementations that were roughly pixel equivalent
heycam: well ideally the
definitions of the filter primitives are precise enough that
you could say that
... the results should equal a certain image +/- a
tolerance
... we could just add raster images and then work out what to
do when it comes to automating
... since we don't have automation yet anyway
... maybe we don't need to worry about 1 pixel differences just
yet
ChrisL: well there are almost no
tests at the moment so it would be better to have something
people can argue over
... I thought of a way to test feDisplacement by covering a red
rectangle
heycam: some of the specs Adobe works on include a testing plan...
krit: not for filters yet
heycam: suppose you wanted to get help with testing, it would be helpful to have a list of what still needs testing
ChrisL: when you look at the tests, the metadata in the tests tells you which section it covers
heycam: so we could start by picking a section that doesn't have any tests
ChrisL: we should also have tests
to cover SVG, not just HTML
... thanks for the status update, that's helpful
ChrisL: the charter went out just
recently
... there's been a change in the W3C
... every charter that goes out needs to have positive
responses from at least 5% of membership
... which equals about 20 members
... so please push your AC reps to respond
<ed> question: Should there be a Co-Facilitator? If so, I would expect the SVG
<ed> Chairs would wish to nominate someone?
ed: there was a mail about the accessibility TF asking who should lead this work from the SVG side
heycam: so they're looking for a co-facilitator from our side?
ed: yes
heycam: if Rich is going to be
heavily involved in the TF then I'd be happy for him to take it
on if he feels comfortable with it
... I'll send a mail to Rich
ChrisL: who else is going to be on it?
heycam: I'll follow the mailing list
krit: I'll be on the call and join the mailing list
Tav: CSS has blocks and
inlines
... do SVG <text> elements behave as blocks and
<tspans> as inlines?
heycam: that's roughly how it works internally in Firefox
<ChrisL> <text> is block, <tspan> is inline
Tav: I was just wondering how to apply some of the CSS properties like line-height to SVG
heycam: if you have specific questions about properties then they would be good things to bring up
ChrisL: I updated the wiki so we have a page for the TPAC now
nikos_: do we know when the FXTF meeting is?
ChrisL: no, but it seems like it might be during the SVG part of the week
heycam: I recall something like
that
... I'll send an email about that
RRSAgent: make minutes public
RRSAgent: make minutes
apologies: Rik, Thomas, Cyril
RRSAgent: make minutes
This is scribe.perl Revision: 1.138 of Date: 2013-04-25 13:59:11 Check for newer version at http://dev.w3.org/cvsweb/~checkout~/2002/scribe/ Guessing input format: RRSAgent_Text_Format (score 1.00) Found ScribeNick: birtles Found Scribe: birtles Inferring ScribeNick: birtles Default Present: [IPcaller], ed, birtles, heycam, krit, stakagi, Tav, ChrisL, nikos_ Present: [IPcaller] ed birtles heycam krit stakagi Tav ChrisL nikos_ Regrets: Rik Thomas Cyril Agenda: https://www.w3.org/Graphics/SVG/WG/wiki/Agenda Found Date: 25 Sep 2014 Guessing minutes URL: http://www.w3.org/2014/09/25-svg-minutes.html People with action items:[End of scribe.perl diagnostic output]