20:28:25 RRSAgent has joined #svg 20:28:25 logging to http://www.w3.org/2013/08/15-svg-irc 20:28:27 RRSAgent, make logs public 20:28:27 Zakim has joined #svg 20:28:29 Zakim, this will be GA_SVGWG 20:28:29 ok, trackbot, I see GA_SVGWG(SVG1)4:30PM already started 20:28:30 Meeting: SVG Working Group Teleconference 20:28:30 Date: 15 August 2013 20:28:31 +krit 20:28:31 -krit 20:28:32 +krit 20:28:57 +[IPcaller] 20:29:04 Zakim, [ is me 20:29:04 +heycam; got it 20:29:30 +cabanier 20:30:29 Chair: Cameron 20:30:33 Agenda: http://lists.w3.org/Archives/Public/public-svg-wg/2013JulSep/0054.html 20:30:35 Regrets: Rich 20:32:17 Dear SVG: Please kill your namespaces faster. Love, Tab. 20:35:57 +nikos 20:37:04 TabAtkins: we would need to add the SVG elements to the HTML parser 20:37:04 scribenick: nikos 20:37:16 krit1++ 20:37:28 But really it's the xlink that's killing me today. 20:37:36 Which requires only local changes to the language. 20:37:36 Topic: Publishing and renaming CSSMatrix 20:37:41 Removing xlink is something we can do without a lot of the other stuff. 20:37:59 I thought we already agree to killing that off 20:38:03 https://dvcs.w3.org/hg/FXTF/raw-file/tip/matrix/index.html 20:38:06 Yeah, but it's not edited in yet. ^_^ 20:38:23 http://dev.w3.org/fxtf/matrix/ 20:38:43 heycam: we haven't published this yet? 20:38:46 krit: correct 20:38:48 krit: 2 issues 20:38:55 krit: first is name. CSS WG doesn't want CSS prefix 20:39:11 heycam: dictionary ones don't matter since they're not exposed in script 20:39:21 ... interfaces intended to be used outside probably shouldn't have css in the name 20:39:35 krit: suggestion was either TransformationMatrix or TransformMatrix 20:39:38 ... I don't have others 20:39:58 heycam: if we named it Matrix, there might be a risk of conflicting with scripts that define Matrix already 20:40:06 krit: we also have conflict with other working groups 20:40:19 ... was discussed on fxtf mailing list 20:40:31 ... was suggested to name it Deprecated Matrix 20:40:34 heycam: ugly name! 20:40:41 cabanier: web gl want to have something more primitive 20:40:56 ... not useful for authors. The reason we are doing this is to make operations easier for them 20:41:15 heycam: I'm not convinced by argument that we shouldn't have it becaues JS authors can write something that can run faster 20:41:29 ... browsers can implement with native js behind the scenes and avoid the overhead 20:42:02 I'm down with TransformMatrix. 20:42:29 krit: because Matrix is so generic, I don't think it's a bad idea to have a prefix 20:43:12 heycam: you said CSS WG has already resolved to publish? what was their final view on name? have an issue in the spec? 20:43:23 krit: we need the name for the url though so it's problematic to do that 20:43:40 heycam: I think it would be fine, even if we call it CSSMatrix or TranformMatrix to have the matrix as just url 20:43:51 s/matrix as just url/url as just matrix 20:44:04 heycam: I'm fine with publishing and including an issue 20:44:17 krit: CSS WG suggested SVG WG takes care of publication 20:44:28 heycam: couple of other issues open in the spec 20:44:40 ... 1. w part of the point 20:44:46 krit: the main is whether we use float or doubles 20:45:28 krit: Mozilla wants floats. Apple wants double 20:45:44 krit: difference is 10 times on mobile 20:46:03 krit: javascript just uses double 20:46:11 ... so it's just the internal calculation results 20:46:22 ... currently I am using doubles in the spec 20:46:30 heycam: I don't think we need to resolve that before publishing 20:46:54 heycam: what is the plan for replacing SVGMatrix with CSSMatrix? 20:47:11 krit: The whole point of this is to replace SVGMatrix 20:47:35 heycam: so we'll just use CSSMatrix. Won't have any inheritance. 20:47:55 krit: It's backwards compatible, except the new matrix won't throw exceptions as SVGMatrix did 20:48:36 heycam: I also remember roc was concerned about the matrix object being used for 3d and 2d 20:48:45 ... meaning you need the extra components 20:48:56 krit: I think he's ok with it now 20:49:10 heycam: I'll check with him 20:50:54 resolution: Publish first public working draft of new matrix specification 20:51:23 action: Cameron to organise FPWD publication of new matrix specification 20:51:24 Created ACTION-3517 - Organise fpwd publication of new matrix specification [on Cameron McCormack - due 2013-08-22]. 20:52:01 Topic: Progress on subregions hinting in SVG Filters 20:52:13 http://www.w3.org/Graphics/fx/wiki/Filter_effects 20:52:43 krit: Erik put together an implementation matrix 20:53:12 krit: We need to specify exactly how subregions are calculated 20:53:27 ... I would like feedback on the table 20:53:34 ... especially where we have question marks 20:53:48 ... we're not clear on how to calculate subregions for some filters at the moment 20:54:28 krit: it's important that the filter region doesn't clip things you don't want clipped 20:54:36 ... a lot of people don't understand the 10% margin 20:54:45 heycam: I never liked it. It's not usually what you want 20:54:57 ... are you suggesting to remove filter region primitive attribute? 20:55:08 krit: no 20:55:20 ... if they are not present then the user agent should calculate automatically 20:55:28 heycam: so changing the default 20:55:34 krit: in a way that fixes content 20:55:38 heycam: I'd be in favour of that 20:55:54 krit: so we need to specify what unbound? is for each in the table 20:56:41 heycam: for filters like feFlood or feTurbulence that conceptually have infinite output, what would we define apart from 'implementation needs to work out how much of the final rendered element to keep' 20:56:59 krit: we could specify 120%. it's not nice though 20:57:13 heycam: can't we just state it needs to be large enough so that it doesn't affect filter output? 20:57:50 krit: If you use feFlood and it will fill the whole SVG file. 20:58:02 ... could use the viewPort 20:58:07 heycam: feFlood is a special case though 20:58:42 ... why can't we say something like 'minimal area based on how that filter primitive is used in the filter chain' 20:59:07 krit: Need to specify that content looks equal on all implementations 20:59:22 heycam: I think that can be achieved by saying the filter primitive is big enough so that it doesn't look different 21:00:17 ... when the element is rendered, there will be some clipping at some point 21:00:31 ... then you can determine the smallest rectangle based on how it is used in the filter chain 21:00:52 ... we can require UAs to generate the filter primitive at the required siz 21:00:57 s/siz/size 21:01:03 krit: I agree. feFlood is still the problem though 21:01:33 heycam: If you didn't have any other clipping, then feFlood would fill the viewport 21:02:15 krit: Would have to check about breaking content 21:02:37 heycam: do you feel we need to specify how to calculate the area for that primitive? 21:02:41 krit: I think that's a good idea 21:02:51 ... to ensure consistency between implementations 21:03:12 heycam: I'd be fine if we had something like that written down. Do you want to do that? 21:03:13 krit: yes 21:03:46 action: Dirk to specify how to calculate automatic filter region for unbounded primitives 21:03:47 Created ACTION-3518 - Specify how to calculate automatic filter region for unbounded primitives [on Dirk Schulze - due 2013-08-22]. 21:04:01 Topic: Collapsing CSS Filter functions and the problem of color clamping on 21:04:01 intermediate results 21:04:24 krit: a lot of filter effects short hands can be represented with a colour matrix 21:04:45 ... ideally you can collapse the filter chain to a single operation on the matrix 21:04:57 ... but we currently define that values should be clamped at each stage 21:05:23 ... do we want to keep current behaviour or can we relax the specification to allow optimisation in this case? 21:05:48 +Doug_Schepers 21:05:51 ... it's a balance between performance and ease of authoring 21:06:19 heycam: is there a benefit to clamping at each filter? is that something authors would need or want? 21:07:10 heycam: there are similar thinks in CSS with colour values 21:07:32 ... I can't remember where exactly but it talks about allowing values to go out of range and clamp in the final step 21:07:37 ... so there might be precedence 21:08:27 nikos: I think it would be confusing for authors to get different results depending on whether a shorthand is used or not 21:08:53 s/colour/color/g 21:08:54 heycam: my feeling is that we should allow intermediate results to go out of range and clamp at the end 21:08:55 :D 21:10:04 krit: initially I was for clamping at the end. Now i'm not sure. There are cases where you can guarantee that you don't need to clamp 21:10:12 ... so I support clamping at each step now 21:10:24 heycam: I can't see an author use for clamping each stage 21:10:35 ... if there was one I think it would be better to have explicit control to opt in to that 21:10:54 krit: there is another case. contrast 200% then another filter primitive with contrast 50% and they wonder why they don't get the same result 21:11:12 ...it's a corner case though. I don't think it's actually useful to do that. 21:11:57 heycam: I can imagine cases where an image has colour values that are almost fully bright and you apply a brightness filter and you want to clamp 21:12:51 heycam: I'm not sure which I prefer 21:12:55 krit: I think we should keep the clamping for now 21:13:50 shepazu: I've seen some pretty crazy stuff come out of authoring tools 21:14:15 heycam: I'm not sure how much performance benefit there is from collapsing down to a single operation on a colour matrix 21:14:47 ... I think implementations often slow down with filters because they are creating lots of off-screen surfaces 21:15:03 ... here that shouldn't matter as you can work on the same surface 21:16:28 resolution: maintain clamping colour matrices for filter effects at each step in the filter chain 21:16:43 Topic: Geometry API and Accessible SVG Community Groups 21:16:59 shepazu: there are 2 community groups you guys might be interested in 21:17:04 1. SVG accessibility 21:17:23 http://www.w3.org/community/svga11y/ 21:17:25 http://www.w3.org/community/svga11y/2013/08/15/roadmap/ 21:17:42 2. geometry API 21:18:18 http://www.w3.org/community/geometryapi/wiki/Use_Cases_and_Requirements 21:18:18 http://www.w3.org/community/geometryapi/ 21:18:19 use cases and requirements doc (in progress) 21:18:53 SVG accessibility is unclear. There's few normative requirements, a lot comes from the doc that Charles wrote about mapping and authoring guidelines 21:19:06 shepazu: very old. refers to SVG 1.0 21:19:31 ... After talking to accessibility experts. The state of SVG is ok, but there's a lot of tests that need to be run 21:19:45 ... so the whole point of this group is to write tests and write requirements 21:19:57 ... we're going to have a workshop/hackathon 21:20:12 heycam: sounds good. for me I don't feel I have the knowledge to know what we need to change in SVG 21:20:20 krit: who would attend the workshop? 21:20:33 shepazu: there's about 16 people in the group now. 21:21:38 ... we want: 1. Accessibility experts who can help us test. 2. People who use accessibility features. 3. SVG people 21:21:57 ... and at least one 'testing' expert 21:23:05 ... I gave a presentation about accessible data visualisation and people were really interested 21:23:10 ... that's where this came from 21:23:41 ... first step is to make a bunch of tests, run them and create an implementation report 21:26:07 nikos: what's the make up of the group. Who do you need? 21:26:31 shepazu: we have lots of interested accessibility experts. 21:26:43 ... they should be able to find people who use accessibility features 21:27:13 ... there's two or three people who are pretty good with SVG 21:27:18 ... would be good to have Rich in the group 21:27:28 ... looking for someone from Adobe 21:27:43 ... I'm looking at September for the hackathon 21:29:18 ... October at the graphical web would be good. Cyril, Tav, and Nikos will be there 21:30:35 ... so we can chat about that and try to organise a time that is good for everyone 21:30:55 shepazu: The other group is the geometry API community group 21:31:06 ... the goal there is to come up with a geometry api (SURPRISE!) 21:31:34 ... we want to meet use cases for SVG primarily. But if we satisfies use cases for other web tech that's ok. 21:31:47 ... I want to be able to do things like calculate intersection of shapes 21:35:57 cabanier: Dirk and I signed up 21:36:26 shepazu: If we can come out with a simple set of use cases and requirements that we might include in SVG 2 21:36:38 krit: should get some SKIA guys in the group 21:38:26 cabanier: is this part of SVG or is it just something that interfaces with SVG? 21:38:51 shepazu: I guess you could interact with other web tech 21:39:08 krit: it would be great to have a document that everyone could reference 21:39:53 shepazu: it would be good to have more people in the group to define the use cases that are important 21:40:18 ... it would be good to have a matrix library (SKIA has), point and vector maths 21:40:23 ... need to drive requirements on those 21:41:04 ... in conclusion. It would be good to get people into the groups to drive the conversation and keep them going 21:41:23 -cabanier 21:41:25 -heycam 21:42:34 -krit 21:43:27 -nikos 21:43:28 -Doug_Schepers 21:43:35 RRSAgent, make minutes 21:43:35 I have made the request to generate http://www.w3.org/2013/08/15-svg-minutes.html nikos 21:46:59 krit has joined #svg 21:47:50 - +1.425.373.aaaa 21:47:51 GA_SVGWG(SVG1)4:30PM has ended 21:47:51 Attendees were +1.425.373.aaaa, krit, [IPcaller], heycam, cabanier, nikos, Doug_Schepers 23:17:49 birtles has joined #svg 23:22:23 jaseg has joined #svg 23:50:08 thorton has joined #svg