- From: Chris Lilley <chris@w3.org>
- Date: Mon, 11 Oct 2010 23:06:41 +0200
- To: public-fx@w3.org
Hello public-fx, http://www.w3.org/2010/10/11-fx-minutes.html and below as text CSS-SVG Task Force Teleconference 11 Oct 2010 [2]Agenda [2] http://lists.w3.org/Archives/Public/public-fx/2010OctDec/0008.html See also: [3]IRC log [3] http://www.w3.org/2010/10/11-fx-irc Attendees Present +1.408.636.aaaa, smfr, ed, ChrisL, Shepazu, anthony Regrets Chair Erik Scribe ChrisL Contents * [4]Topics 1. [5]CSS SVG transforms update 2. [6]Premultiplied gradients in CSS3 3. [7]'writing-mode' values across CSS and SVG * [8]Summary of Action Items _________________________________________________________ <trackbot> Date: 11 October 2010 <scribe> scribenick: ChrisL CSS SVG transforms update <ed> [9]http://lists.w3.org/Archives/Public/public-fx/2010OctDec/0000.htm l [9] http://lists.w3.org/Archives/Public/public-fx/2010OctDec/0000.html anthony: see [10]http://lists.w3.org/Archives/Public/public-fx/2010OctDec/0000.ht ml [10] http://lists.w3.org/Archives/Public/public-fx/2010OctDec/0000.html and [11]http://dev.w3.org/Graphics-FX/modules/2D-transforms/spec/2DTrans forms.html [11] http://dev.w3.org/Graphics-FX/modules/2D-transforms/spec/2DTransforms.html anthony: sumary at first url, spec at second one ... some email from dr Olaf, pointed out some things <anthony> [12]http://lists.w3.org/Archives/Public/public-fx/2010OctDec/0001.ht ml [12] http://lists.w3.org/Archives/Public/public-fx/2010OctDec/0001.html anthony: mainly concerns related to changes from SVG ds: wish there was a summary anthony: I made one ... changed todo list, added some items ... as follows <anthony> - Address any issues with transform-origin <anthony> - IDL <anthony> - Address if the properties are independent of transform attribute used in SVG (1.1, 1.2) <anthony> - Address if the transform properties are available as presentation attributes <anthony> - Investigate and address backwards incompatibilities (rotate, origin on which transform is applied) <anthony> - Address how to determine the difference between original SVG attribute and new presentation attribute (example) <anthony> - Address if 'transform-origin' property has any influence on appearence of old SVG transform attribute <anthony> - Address issue for objects with no bounding box (e.g. line) smfr: problem with assuming identity is the same as none ... in CSS identity doews something different, establishes a stacking context ... these need to be different values. initial value of none, bt identity as a defined value to start or end from ... transform-origin initial value in SVG? ... 50% 50%? anthony: odd for it to do differnt things in css and svg smfr: how so? ... for pointer events we have a different initial value for svg and html ... could do the same here shepazu: why have it different? smfr: fill and stroke dont translate to html ChrisL: yes that is a perfectly reasonable for pointer-events shepazu: do we have to have it different? ChrisL: if svg already has them and css does not but has stacking contexts then the initial value needs to be different ed: could see how many would brewak with a 50% 50% transform origin ... probably a lot shepazu: can we make it so that both behaviors work in svg somehow anthony: given that transform-origin is not previously part of svg, its new so should not be too much of an issue ... but for transform property it may break ChrisL: if its a property then it always has a value. even in older content that does not specify it explicitly ed: would auto be ok as an initial value ChrisL: our initial value is 0 0 in the local coordinate system. that can't be expressed with percent syntax which is relative to the bbox ed: transform-oriin accepts coordinates? smfr: well, it accepts lengths ... percent is percent of the border box shepazu: how to say 50% of the document? smfr: you can't ChrisL: so the initial value for svg is 0 0 which is relative to the local coordinate system <ed> ED: so if we go for "0 0" as the initial value for svg, you would just have to specify transform-origin:center to get the 50%,50% behaviour, not that much work really smfr: in svg, bbox is pre-transform? ChrisL: yes shepazu: can you have an api to get the bbox? smfr: yes there is one that gets the bbox of the transformed element. awkward when it maps to screen space ... existing apis use bbox ... have also had request for api to map local to global coordinate system shepazu; dom3 has a request to hace such an api, jwatt made that request scribe: anticipate html/css will need that shepazu (lloks for link) <shepazu> [13]http://lists.w3.org/Archives/Public/www-dom/2010OctDec/0013.html [13] http://lists.w3.org/Archives/Public/www-dom/2010OctDec/0013.html smfr: resisted giving the cuulative transform, because with 3d transforms flattening can occur, to put a plane in another 3d space so its hard to describe the whole thing anthony: yes you would need a whole transform list ... happy to go with the group. initial value for transform-origin, would be nice to be the center, and then somehow ... ChrisL: that would change behaviour for existing content in new and old implementations. it would break all existing content that uses transforms ed: resolution? resolution: initial value of transform-origin is auto, which in svg means 0 0 and in html/css means 50% 50% smfr; so using css to apply this to svg would have the traditional 0,0 origin point? ChrisL: yes <scribe> ACTION: anthony to add the new initial value of transform-origin to the spec [recorded in [14]http://www.w3.org/2010/10/11-fx-minutes.html#action01] <trackbot> Created ACTION-17 - Add the new initial value of transform-origin to the spec [on Anthony Grasso - due 2010-10-18]. Premultiplied gradients in CSS3 [15]http://www.w3.org/mid/B53F84D2-D549-4472-A7AE-CCDE9563E1D3@me.co m [15] http://www.w3.org/mid/B53F84D2-D549-4472-A7AE-CCDE9563E1D3@me.com [16]http://lists.w3.org/Archives/Public/www-svg/2006Jan/0342.html [16] http://lists.w3.org/Archives/Public/www-svg/2006Jan/0342.html [17]http://lists.w3.org/Archives/Public/www-svg/2006Jul/0050.html [17] http://lists.w3.org/Archives/Public/www-svg/2006Jul/0050.html ed: css3 seems to want to have premultipied gradients, different from canvas and svg smfr: otherwise gradient from red to transparent has grey in it ChrisL; that is because transparent is rgba(0000) which is transparent black scribe: if you want a fade to red, fade to transparent red not transparent black ed: people would want the css3 gradient systax with canvas and svg. they will be surprised smfr: could we add a value to color interpolation to say its premultiplied ChrisL: also in premultiplied, lower resolution for colors as the transparency goes up smfr: so options are to pushback on premultiplied, or to add a value to allow controlling the interpolation ed: not that difficult to add shepazu: more properties ed: no, existing property with one new value ChrisL: concerned about hue shifts with fades of pastel colors <ed> [18]http://www.w3.org/TR/SVG11/painting.html#ColorInterpolationPrope rty [18] http://www.w3.org/TR/SVG11/painting.html#ColorInterpolationProperty smfr: we use premultipiied already for gradients in safari and firefox, certainly for transitions we use premultiplied ... underlying lirary on mac does not give us a choice ... chris, please post an example <scribe> ACTION: chris post examples of reduced resolution with premultiplied colors [recorded in [19]http://www.w3.org/2010/10/11-fx-minutes.html#action02] <trackbot> Created ACTION-18 - Post examples of reduced resolution with premultiplied colors [on Chris Lilley - due 2010-10-18]. smfr: we use this for color transitions and for css3 gradients. that spec is not finished though 'writing-mode' values across CSS and SVG ed: hoped to have elika here for this one ... [20]http://www.w3.org/Graphics/fx/track/issues/3 [20] http://www.w3.org/Graphics/fx/track/issues/3 [21]http://www.w3.org/mid/4C2B18DD.6020209@w3.org [21] http://www.w3.org/mid/4C2B18DD.6020209@w3.org [22]http://dev.w3.org/csswg/css3-text-layout/test-writing-mode-direc tion.svg [22] http://dev.w3.org/csswg/css3-text-layout/test-writing-mode-direction.svg all implementations do different things with writing-mode. want to alighn with svg but there is inconsistet implementation behaviour scribe: wanted to see if spec defines correct behaviour ChrisL: do we have a table of results for different implementations on that test? ed: no. put this topic off until elika is here ... batik does 123 on second line in orange, in differnt way to opera. not well tested code in opera, not much used ... not that well defined in spec either. ChrisL: good topic for tpac, needs a whiteboard anthony: hope to be there ed: will be there too ... good to define transforms more at tpac too adjourned <scribe> agenda: [23]http://lists.w3.org/Archives/Public/public-fx/2010OctDec/0008.ht ml [23] http://lists.w3.org/Archives/Public/public-fx/2010OctDec/0008.html Summary of Action Items [NEW] ACTION: anthony to add the new initial value of transform-origin to the spec [recorded in [24]http://www.w3.org/2010/10/11-fx-minutes.html#action01] [NEW] ACTION: chris post examples of reduced resolution with premultiplied colors [recorded in [25]http://www.w3.org/2010/10/11-fx-minutes.html#action02] [End of minutes] -- Chris Lilley Technical Director, Interaction Domain W3C Graphics Activity Lead, Fonts Activity Lead Co-Chair, W3C Hypertext CG Member, CSS, WebFonts, SVG Working Groups
Received on Monday, 11 October 2010 21:06:46 UTC