19:26:28 <RRSAgent> RRSAgent has joined #svg
19:26:28 <RRSAgent> logging to http://www.w3.org/2009/02/26-svg-irc
19:26:30 <trackbot> RRSAgent, make logs public
19:26:32 <trackbot> Zakim, this will be GA_SVGWG
19:26:32 <Zakim> ok, trackbot; I see GA_SVGWG()2:30PM scheduled to start in 4 minutes
19:26:33 <trackbot> Meeting: SVG Working Group Teleconference
19:26:33 <trackbot> Date: 26 February 2009
19:29:56 <ChrisL> ChrisL has joined #svg
19:30:23 <ed__> ed__ has joined #svg
19:30:27 <Zakim> GA_SVGWG()2:30PM has now started
19:30:28 <Zakim> +Shepazu
19:31:33 <Zakim> +??P8
19:31:40 <Zakim> +??P13
19:31:43 <heycam> Zakim, ??P13 is me
19:31:43 <Zakim> +heycam; got it
19:31:43 <ed__> Zakim, ??P8 is me
19:31:44 <Zakim> +ed__; got it
19:32:43 <Zakim> +??P14
19:32:56 <ChrisL> zakim, who is here?
19:32:56 <Zakim> On the phone I see Shepazu, ed__, heycam, ??P14
19:32:57 <Zakim> On IRC I see ed__, ChrisL, RRSAgent, Zakim, heycam, anthony, shepazu, ed_work, trackbot
19:33:18 <Zakim> -heycam
19:33:23 <Zakim> -??P14
19:33:35 <ChrisL> present+ a dalek
19:33:44 <Zakim> +??P2
19:33:46 <heycam> Zakim, ??P2 is me
19:33:46 <Zakim> +heycam; got it
19:33:59 <ChrisL> rrsagent, here
19:33:59 <RRSAgent> See http://www.w3.org/2009/02/26-svg-irc#T19-33-59
19:34:15 <Zakim> +??P5
19:34:53 <ChrisL> zakim, ?/p5 is me
19:34:53 <Zakim> sorry, ChrisL, I do not recognize a party named '?/p5'
19:35:02 <ChrisL> zakim, ??p5 is me
19:35:02 <Zakim> +ChrisL; got it
19:35:38 <ed__> Zakim, who's here?
19:35:38 <Zakim> On the phone I see Shepazu, ed__, heycam, ChrisL
19:35:39 <Zakim> On IRC I see ed__, ChrisL, RRSAgent, Zakim, heycam, anthony, shepazu, ed_work, trackbot
19:36:44 <ChrisL> zakim, who all is here, y'all
19:36:44 <Zakim> I don't understand 'who all is here, y'all', ChrisL
19:37:15 <Zakim> +[IPcaller]
19:37:37 <anthony> Zakim, [IPcaller is me
19:37:37 <Zakim> +anthony; got it
19:37:54 <ed__> Zakim, pick a victim
19:37:54 <Zakim> Not knowing who is chairing or who scribed recently, I propose ChrisL
19:38:00 <ChrisL> scribe: chris
19:38:11 <ChrisL> scribenick: chrisl
19:38:11 <ed__> Agenda: http://lists.w3.org/Archives/Public/public-svg-wg/2009JanMar/0172.html
19:38:17 <shepazu> zakim, pick a victim
19:38:17 <Zakim> Not knowing who is chairing or who scribed recently, I propose ed__
19:38:37 <ChrisL> Topic: Referencing ISO-32000-1 for blending [Compositing module]
19:39:42 <ChrisL> cl: is this a normative or informative reference, and will the equations be in our spec of just referenced?
19:39:48 <ChrisL> cmc: costs money?
19:39:51 <ChrisL> cl: of course
19:40:13 <ChrisL> ds: prefer to have the equations in our spec, can reference the ISO as well
19:40:23 <ChrisL> ... and better to be in a RF spec
19:40:54 <ChrisL> cl: normative or informative?
19:41:08 <ChrisL> ds: informative. Useful to know the connection between them
19:41:20 <ChrisL> cl: agree
19:41:44 <ChrisL> cmc: if its nortmative then you still should buy it in case
19:41:55 <ChrisL> ed: good to have all the equations in our spec
19:42:31 <ChrisL> resolved: equations for compositing will be in the svg spec, with an informative reference to ISO 3200-1
19:43:12 <ChrisL> action: anthony to check equations for blending and add informative ref to ISO 32000-1
19:43:12 <trackbot> Created ACTION-2480 - Check equations for blending and add informative ref to ISO 32000-1 [on Anthony Grasso - due 2009-03-05].
19:43:27 <ChrisL> ag: will do, not checked the equations yet
19:44:24 <ChrisL> ... will check the equations again, needs some testing to verify
19:47:14 <ChrisL> topic: transforms review
19:47:21 <anthony> http://www.w3.org/Graphics/SVG/WG/wiki/CSS-Transforms-Review
19:47:50 <ChrisL> http://dev.w3.org/cvsweb/~checkout~/csswg/css3-2d-transforms/Overview.html?rev=1.3&content-type=text/html;%20charset=iso-8859-1
19:49:38 <ChrisL> cl: (explains stacking context)
19:49:48 <ChrisL> ds: liked your email comments, chris
19:50:54 <shepazu> s/ liked your email comments, chris/ liked your email comments, chris... they seem more likely to be fruitful/
19:50:54 <ChrisL> before "Currently, Firefox and Safari throw away" say "Since backward compatibility is important we tested current browwsers and currently ...."
19:51:48 <ChrisL> should probably motivate why openvg is important
19:52:46 <ChrisL> existing implementations get acceleration from openvg, etc
19:53:31 <ChrisL> cl: the overasll review document is good, I just had some specific comments
19:55:29 <ChrisL> ds: its important that we support css in this useful work
19:55:33 <ChrisL> ed: sounds good
19:55:52 <ChrisL> ag: been editing live, these are ready to go
19:56:02 <ChrisL> cmc: i have a few detailed comments in email
19:56:13 <ChrisL> .. want clarification on matrix sizes and math
19:56:28 <ChrisL> ag: need to commit the new draft of svg transforms
19:57:24 <ChrisL> cl: the css spec needs some references to explain transforms and matrices for those unaware
20:00:32 <ChrisL> ed: we have a minuted resolution to publish
20:00:55 <ChrisL> ds: plh said recently that tight integration and strong coordination is important
20:02:59 <ChrisL> ag: did we respond to dean's email?
20:03:20 <ChrisL> cmc: send a reply to dean thanking him, and point to this review?
20:04:42 <ChrisL> action: doug to reply to Dean on 3d transforms
20:04:42 <trackbot> Created ACTION-2481 - Reply to Dean on 3d transforms [on Doug Schepers - due 2009-03-05].
20:05:31 <ChrisL> referencing http://www.w3.org/Graphics/SVG/WG/wiki/CSS-Transforms-Review
20:06:13 <ChrisL> cmc: i still have some comments yet to make
20:06:32 <ChrisL> ds: ok lets talks offline and I will send it over the weekend
20:06:47 <ChrisL> cl: css wg will likely be discussing these documents next week in japan
20:07:17 <ChrisL> Topic: Transitions and Animations
20:07:48 <ChrisL> cmc: so we are going to send outr individual non-svgf related stuff directly, and coordinate on a wg response for the svg specific aspects
20:09:23 <ChrisL> ds: think individual responses is more timely and allows more discussion
20:10:15 <ChrisL> ... send responses to www-style with cc to www-svg
20:11:06 <ChrisL> ed: i have a bunch of feedback on that, will send it next week
20:15:16 <ChrisL> topic: z-index use cases and requirements
20:15:23 <ChrisL> issue-2226?
20:15:23 <trackbot> ISSUE-2226 -- Investigate the use cases and requirements for z-index -- RAISED
20:15:23 <trackbot> http://www.w3.org/Graphics/SVG/WG/track/issues/2226
20:15:56 <ChrisL> ed: good to have an action on this.
20:16:10 <ChrisL> ... does our spec deal with z-index?
20:16:19 <ChrisL> ag: we have discussed it, in Sydney
20:16:50 <ChrisL> http://www.w3.org/2009/02/15-svg-minutes.html#item05
20:18:39 <ChrisL> pointer to stacking context  http://www.w3.org/TR/CSS21/zindex.html
20:19:57 <ChrisL> ed: we could define z-index the same way so that it also applies to svg as well as being compatible with html
20:20:14 <ChrisL> 'z-index'
20:20:15 <ChrisL>     Value:  	auto | <integer> | inherit
20:20:15 <ChrisL>     Initial:  	auto
20:20:15 <ChrisL>     Applies to:  	positioned elements
20:20:15 <ChrisL>     Inherited:  	no
20:20:15 <ChrisL>     Percentages:  	N/A
20:20:17 <ChrisL>     Media:  	visual
20:20:19 <ChrisL>     Computed value:  	as specified 
20:21:10 <ChrisL> ag: instead of z-index, could also use the transform-style property, to switch on z-ordering for a group of objects
20:22:16 <ChrisL> cl: interesting option
20:22:28 <ChrisL> ag: yes as it could apply only to container elements
20:22:34 <ChrisL> ... similar to layered groups
20:23:05 <ed___> ed___ has joined #svg
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20:23:52 <Zakim> -ed__
20:23:54 <ChrisL> ag: as soon as document order is lost, impact on streaming and rendering speed so being able to isolate the effects is beneficial
20:24:25 <ChrisL> ds: would that need a whole shadow tree?
20:24:30 <Zakim> +??P1
20:24:30 <ed_____> ed_____ has joined #svg
20:24:52 <ChrisL> zakim, ??p1 is erik
20:24:52 <Zakim> +erik; got it
20:25:34 <Zakim> -erik
20:25:40 <ChrisL> ds: if we have layered groups, it could be implemented by making a shadow tree that replaces the docuent order subtree. but that could be expensive on memory
20:26:26 <ed___> ed___ has joined #svg
20:26:39 <ChrisL> cl: impact on filter effects / render background, and on event bubbling .....
20:26:54 <Zakim> +??P1
20:26:57 <ChrisL> cmc: would complicate document updates as well
20:27:02 <ChrisL> zakim, ??p1 is erik
20:27:02 <Zakim> +erik; got it
20:27:19 <ed___> rrsagent, pointer?
20:27:19 <RRSAgent> See http://www.w3.org/2009/02/26-svg-irc#T20-27-19
20:27:51 <ChrisL> ds: maybe contact andrew and ask about layeredg
20:28:14 <ChrisL> ed: think you just need a different tree traversal order, not a whole copy of the subtree
20:28:35 <ChrisL> ds; impact of that on keyboard navigation / docuent order?
20:29:58 <ChrisL> ds: would this affect hierarchy eg with a use element that points outside the z-ordered group
20:30:32 <ChrisL> ... example of two circles bing twiddled on z-order, then two use elements that point to them
20:31:04 <ChrisL> ag: i would say no, it gets really complex. import the transform not the layered group it could get really hairy
20:31:26 <ChrisL> ds: right, using them outside the layering context gets document order not this new rendering order
20:32:23 <ChrisL> ag: trying to ease implementor burden while keepin git simple and powerful for authors
20:32:37 <shepazu> <layer><circle id="c1" .../><circle id="c2" .../></layer><use xlink:href="#c1" .../><use xlink:href="#c2" .../>
20:34:00 <ChrisL> ag; a reference to that ISO spec (for full title, for the references)  http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=51502
20:34:31 <ChrisL> ds: need to name this carefully, eg inkscape already has laters that are really more like groups
20:35:10 <ChrisL> costs   CHF 380,00
20:35:56 <ChrisL> ed: so its good to gather use cases and requirements for z-index
20:36:07 <ChrisL> ag: does this impact the transforms UC&R?
20:36:20 <ChrisL> ed: should still examone the use case for it
20:37:08 <ChrisL> cl: good in the transforms UC&R to discuss how this is similar to, and different from, xss 2.1 z-index
20:37:46 <ed___> s/xss/css/
20:38:29 <anthony> s/examone/examine/
20:40:31 <ChrisL> action: anthony draft use cases and requirements for z-index and compare and contrast with transforms and critically discuss with reference to a neo-marxist dialictic
20:40:31 <trackbot> Created ACTION-2482 - Draft use cases and requirements for z-index and compare and contrast with transforms and critically discuss with reference to a neo-marxist dialictic [on Anthony Grasso - due 2009-03-05].
20:41:18 <ChrisL> topic: tpac 2009
20:41:23 <ed___> http://lists.w3.org/Archives/Public/public-svg-wg/2009JanMar/0174.html
20:43:10 <ChrisL> cl: (explains tpac question - group attendance, timing, cost and location)
20:43:54 <ChrisL> ds: an advantage of the proposed location is silicon valley so more particiation from browser vendors like mozilla, applle etc
20:44:29 <ChrisL> http://lists.w3.org/Archives/Member/chairs/2009JanMar/0059
20:44:48 <ChrisL> ds: its one month after svg open in the same area
20:45:25 <ChrisL> cl; prefer the cost-effective location
20:45:50 <ChrisL> ds: perhaps shift svg open?
20:46:12 <ChrisL> cl: not clear that the tpac will happen. depends on how many groups confirm
20:47:20 <ChrisL> ... plh suggested a mini-tpac for browser-based technologies like html, css, svg, webapps and so forth
20:48:53 <ChrisL> ed: mini-tech plenarry sounds good
20:49:12 <ChrisL> s/rry/ry/
20:50:22 <ChrisL> ds: downside is that we miss being able to meet with other groups
20:52:34 <ChrisL> http://www.w3.org/2002/09/wbs/34786/TPAC2009/results
20:58:42 <ChrisL> ds: this has an impact on level of detail
20:58:51 <ChrisL> ag: we need near and far clipping really
20:59:15 <ChrisL> ag: this is 3d transforms applied toa 2d object then flattened to give a 2d result
21:00:10 <ChrisL> topic; back to transforms
21:00:24 <shepazu> s/this has an impact on level of detail/3d Transforms have an impact on level of detail/
21:00:26 <ChrisL> oops, should have changed topic sorrry
21:00:45 <Zakim> -anthony
21:01:43 <ChrisL> topic; odf and svg
21:01:49 <ChrisL> s/;/:/g
21:02:25 <ChrisL> ds: it would be a win if odf were to use svg natively. currently they don't. its being discussed in svg ig
21:02:36 <ChrisL> ... who is interested?
21:02:41 <ChrisL> ed; yes, sure
21:02:48 <ChrisL> s/;/:/g
21:02:59 <ChrisL> zakim, list attendees
21:02:59 <Zakim> As of this point the attendees have been Shepazu, heycam, ed__, ChrisL, [IPcaller], anthony, erik
21:03:00 <anthony> anthony has joined #svg
21:03:25 <Zakim> -ChrisL
21:03:27 <Zakim> -heycam
21:03:29 <Zakim> -erik
21:03:30 <ChrisL> rrsagent, make minutes
21:03:30 <RRSAgent> I have made the request to generate http://www.w3.org/2009/02/26-svg-minutes.html ChrisL
21:03:37 <ChrisL> chair: erik
21:03:40 <ChrisL> rrsagent, make minutes
21:03:40 <RRSAgent> I have made the request to generate http://www.w3.org/2009/02/26-svg-minutes.html ChrisL
21:04:04 <ChrisL> rrsagent, make logs public
21:04:08 <ChrisL> rrsagent, make minutes
21:04:08 <RRSAgent> I have made the request to generate http://www.w3.org/2009/02/26-svg-minutes.html ChrisL
21:04:20 <Zakim> -Shepazu
21:04:22 <Zakim> GA_SVGWG()2:30PM has ended
21:04:24 <Zakim> Attendees were Shepazu, heycam, ed__, ChrisL, [IPcaller], anthony, erik
21:07:50 <anthony> anthony has joined #svg
21:16:09 <ed__> ed__ has joined #svg
22:06:44 <heycam> heycam has joined #svg
22:26:15 <shepazu> heycam: who's this "https" guy?
22:27:28 <heycam> yeah :)
22:27:56 <heycam> i noticed that in one of our minutes from last week
22:53:57 <heycam> anthony, thanks
22:54:09 <heycam> i'm reading through ChrisL's pdf at the moment
23:01:26 <heycam> anthony, what happens if we use a negative number for the 'perspective' property?
23:03:59 <anthony> means that the viewing distance is on the other side of the plane... but I'll have to test what happens exactly - I think the perspective effect is essentially flipped
23:04:23 <anthony> plane ---> X-Y plane where Z=0
23:04:55 <heycam> yeah.  i guess layeredG or whatever mechanism used to decide the painting order would need to take that into account.
23:05:47 <heycam> so with our spec, the only projection transform you can do is the perspective one where the viewing point is (0,0,z)
23:06:15 <heycam> but you can always use translate/rotate to choose a new viewing point, right?
23:06:47 <anthony> correct in both cases. The syntax is actually perspective(x y z)
23:07:04 <anthony> so you can move the viewing point on the X Y plan if you wish
23:07:15 <heycam> oh ok
23:07:22 <heycam> for the css one?
23:07:48 <anthony> CSS has perspective(z) and perspective-origin(x,y)
23:07:53 <heycam> oh
23:08:05 <heycam> so we allow a perspective(x y z)?
23:08:26 <anthony> yeah, we effectively combine the two
23:08:35 <heycam> oh in our spec it sometimes talks about 'perspective' and sometimes 'perspective-point'
23:08:45 <anthony> nah, I've made changes to fix that
23:08:50 <anthony> just need to commit them
23:08:55 <heycam> k
23:09:06 <anthony> the old spec was terrible very confusing
23:09:16 <anthony> ooops missed a ","
23:09:16 <Zakim> Zakim has left #svg
23:09:26 <heycam> and we can only do a single vanishing point, whereas the 4x4 matrix can do two and three
23:09:39 <heycam> what are multiple vanishing points useful for anyway?
23:10:32 <anthony> one example is a corner street view
23:10:34 <anthony> http://gatewayhsart.files.wordpress.com/2008/12/perspective-street_corner.jpg
23:11:27 <heycam> ah, interesting
23:11:34 <heycam> so we couldn't do that
23:12:48 <anthony> in short no. but you could construct that scene still using what we have
23:13:09 <anthony> given that the objects we deal with are 2D in a 3D space I'm not sure of the use case for 2 or 3 vanishing points
23:13:35 <anthony> like if we were dealing with 3D objects in 3D space then... yeah big limitation
23:13:37 <heycam> ok, you could have two groups with different perspective transforms
23:13:44 <anthony> correct
23:13:47 <anthony> also
23:13:47 <heycam> one group for each street
23:13:52 <anthony> here is an example of 3 point
23:13:54 <anthony> http://www.atpm.com/9.09/images/design-three_point.gif
23:14:35 <anthony> having said that - I'm still open to suggestions though
23:14:37 <heycam> oh, cool
23:14:44 <heycam> so what does normal eyesight do?
23:14:54 <anthony> 1 point perspective
23:15:04 <heycam> in the direction that you're facing, i suppose
23:15:08 <anthony> yup
23:15:10 <heycam> well, looking :)
23:15:13 <heycam> ok
23:15:34 <heycam> so it would be good to ask csswg if it's worth supporting these multiple vanishing points then
23:16:18 <anthony> well actually in a way we do see two points if we are looking at a corner
23:16:52 <anthony> but it's hard to focus on both
23:19:49 <anthony> but yeah, would like to see the use case for their proposal
23:26:08 <anthony> also, heycam, another big problem is bounding box calculation - CSS hasn't defined this
23:26:20 <anthony> well, neither have we, but I have an idea of how to
23:53:14 <heycam> 2d bounding box?
23:53:16 <heycam> after projection?
23:53:31 <heycam> yeah i guess you might want to get it before or after projection
23:57:41 <anthony> nah, the thing is a bounding box is just that
23:57:43 <anthony> a box
23:58:06 <anthony> so one way of doing it is multiply the bounding box by the Transform matrix ONLY
23:58:17 <anthony> that way you still end up with a box
23:58:51 <heycam> does that give you the same box as doing the projection, then taking the bounding box of that?
23:59:18 <anthony> although one problem with multiplying it by the transform matrix is it could rotate...
23:59:37 <heycam> i mean i guess it's the same as with 2d transforms
23:59:44 <heycam> you get the bbox before the transform, yeah?
23:59:53 <anthony> I guess so