**Username or display name (will be displayed publicly):** [[ https://commons.wikimedia.org/wiki/User:JoKalliauer | JoKalliauer ]], <Looking for help>
**Categories/Tags/Keywords (up to 5):**
#Wikimedia-SVG-rendering, #Commons, #MediaWiki-File-management, #TechCom-RFC, #thumbor
**Session type
(both):**
- [ ] Presentation (including Q/A) - 25 mins
- [x] Discussion (including Q/A) - 55 mins
- [ ] Workshop (including Q/A) - 55 mins
- [x] Lightning talk - 5 mins
I think it would be best to have a lightning talk (maybe in the main track) and following a discussion (maybe in a Jitsi room).
**Venue
(select one):**
[
] I would like to be on the main track
[X] I wouldn't mind being on the main track
[ X] I need a Jitsi room for the session
**When are you available to have the session? **
21.05. 16UTC-22UTC https://www.worldtimebuddy.com/?qm=1&lid=2761369,524901,1816670&h=2761369&date=2021-5-21&sln=18-24&hf=0
22.05. 6UTC-22UTC https://www.worldtimebuddy.com/?qm=1&lid=2761369,524901,1816670&h=2761369&date=2021-5-22&sln=8-24&hf=0
23.05. 6UTC-18UTC https://www.worldtimebuddy.com/?qm=1&lid=2761369,524901,1816670&h=2761369&date=2021-5-23&sln=8-20&hf=0
Since I it is a technical discussion imho heavily depending on boundary conditions and implementation on WMF developers, it might should imho be a Europe-USA time, since important developers in this section seem to be from USA, France, Germany . So I think a side-track(Jitsi) in the "main"-time (16UTC to 19UTC) might be ideal, but I've never been on a Hackaton-converence so you will know it better.
@Developers If you want to participate, it might be best to post you availability below.
### Session Details
**Short description of the session (
175179 words):**
Wikimedia
using an [unmaintained](https://mail.gnome.org/archives/desktop-devel-list/2017-December/msg00072.html) 4 years old software, which is [depreciated since 2017](https://people.gnome.org/~federico/blog/librsvg-24020-is-released.html)re-evaluates the renderer in T40010,
called librsvg 2.40,however it's a complex topic with pros and cons for each render. where even the developer [declares: "do not use librsvg 2.40"](https://people.gnome.org/~federico/blog/do-not-use-librsvg-2.40.x.html) And the SVG-Commons-Community needs a render that can handle svg-features such as [[ https://phabricator.wikimedia.org/T11420 | textPath ]].
To make a decision about a new renderer based on data, I made some independent svg-bechmarks between librsvg 2.50/resvg/Inkscape/batik reported at [[ https://commons.wikimedia.org/wiki/User:JoKalliauer/SVG_test_suites | Commons]] , containing time-benchmarks, correctness-benchmarks, rendering-comparisons of >1000s of svg-images, ... . In 7 out of 7 categories resvg won; [[ https://github.com/RazrFalcon/resvg/ | resvg ]] is a fast renderer with good SVG 1.1-support. However there are open questions, e.g. how to treat/value the draft of SVG 2.0 (e.g. SVG 1.2 got deprecated) or how measure time fairly (should we set a time-out-limit, that influences also the correctnessratio) . Inkscape-Editors often like Inkscape as a render, however Inkscape priorizes additional features over correct rendering [(ref)](https://gitlab.com/inkscape/inbox/-/issues/4809#note_566052399), leading to invalid svgs that cannot be edited by anything else than inkscape.
From the currently reported librsvg2.40-bugs resvg fixes 45 of 51, inkscape fixes 40 of 51 and librsvg 2.50 fixes 28 of 51 tasks, see [details](https://www.mediawiki.org/wiki/User:JoKalliauer/phab/wikimedia-svg-rendering#table), a comparision of all supported features can checked [here](https://razrfalcon.github.io/resvg-test-suite/svg-support-table.html#Tests_summary).
**Target audience:**
- WMF-developers
- SVG-Editors (To understand why the processes is stuck, since years.)
- librsvg/resvg/Inkscape/batik-developer (But I don't expect them to come- SVG-Editors/Wikimedians (Discuss which svg-features are most important.)
- Wikimedians active on Commons- librsvg/resvg/Inkscape/batik-developer (Which pros&cons they see.)
**What will participants get out of this session? (41 words)**
It should be clear what are the boundary-conditions (e.g. are headless browsers an alternative?), for a benchmark.
The Commons-Communtiy & SVG-Editors should understand the advantages and disavantages that the differnet options.
The WMF-Developers should know what (and why) the Community wants/needs.
**(Optional) Additional resources:**
- T40010 RFC: Re-evaluate librsvg as SVG renderer on Wikimedia wikis
-- [inkscape#4809](https://gitlab.com/inkscape/inbox/-/issues/4809) Inkscape-Disussion: Wikimedia re-evaluates svg-renderer
-- [librsvg#729](https://gitlab.gnome.org/GNOME/librsvg/-/issues/729) librsvg-RFC Wikimedia re-evaluates svg-renderer
-- [resvg#386](https://github.com/RazrFalcon/resvg/issues/386) resvgRFC Wikimedia re-evaluates svg-renderer
- librsvg-developer about librsvg 2.40
-- [2017 anounced to be the last version](https://mail.gnome.org/archives/desktop-devel-list/2017-December/msg00072.html)
-- [2017 deapreciated](https://people.gnome.org/~federico/blog/librsvg-24020-is-released.html)
-- [2020 do not use librsvg 2.40 by the librsvg-developer](https://people.gnome.org/~federico/blog/do-not-use-librsvg-2.40.x.html)
- [svg-feature-support-table](https://razrfalcon.github.io/resvg-test-suite/svg-support-table.html) between resvg/Chrome/Firefox/Batik/Inkscape/librsvg/...
- Wikipedia about librsvg 2.40-bugs
-- [en:Wikipedia:SVG help](https://en.wikipedia.org/wiki/Wikipedia:SVG_help)
-- [c:librsvg_bugs](https://commons.wikimedia.org/wiki/Librsvg_bugs)
-- [de:Wikipedia:Probleme_mit_SVGs](https://de.wikipedia.org/wiki/Wikipedia:Probleme_mit_SVGs)
-- [c:Category:Pictures_showing_a_librsvg_bug](https://commons.wikimedia.org/wiki/Category:Pictures_showing_a_librsvg_bug)
--- [Category:Pictures_demonstrating_a_librsvg_bug](https://commons.wikimedia.org/wiki/Category:Pictures_demonstrating_a_librsvg_bug)
--- [Category:Pictures_showing_a_librsvg_bug_(overwritten_with_a_workaround)](https://commons.wikimedia.org/wiki/Category:Pictures_showing_a_librsvg_bug_(overwritten_with_a_workaround)) containing 600files
- [table of wikimedia-svg-rendering-tasks](https://www.mediawiki.org/wiki/User:JoKalliauer/phab/wikimedia-svg-rendering#table), most important ones listed below (I try to not link them to this issue)
-- [T 265549](https://phabricator.wikimedia.org/T265549) Update librsvg to > 2.44.10
-- [T 193352](https://phabricator.wikimedia.org/T193352) Update librsvg to ≥2.42.3 (2.44.10)
-- unresolved upstream (selection out of 20 tasks)
--- [T 11420](https://phabricator.wikimedia.org/T11420) textPath is not supported by librsvg
--- [T 36947](https://phabricator.wikimedia.org/T36947) Incorrect text positioning in SVG rasterization (scale/transform; font-size; kerning)
--- [T 205776](https://phabricator.wikimedia.org/T205776) Punjabi letters in SVG files have unnecessary spacing in their corresponding PNG thumbnails
--- [T 142908](https://phabricator.wikimedia.org/T142908) bad kerning of SVG-Rendering of diacritical marks as unicode characters
--- [T 20463 ](https://phabricator.wikimedia.org/T20463) SVG thumbnailing issues - part of the image with <pattern> not rendered
--- [T 154237](https://phabricator.wikimedia.org/T154237) SVG image wikisyntax can't use "lang=zh-hant"
--- [T 261192](https://phabricator.wikimedia.org/T261192) Rendering multilingual (systemLanguage) SVG files fails locally after upgrading librsvg from 2.40.21 to 2.44.10
--- [T 65236 ](https://phabricator.wikimedia.org/T65236) Chinese text in SVG files misplaced and clustered
--- [T 15387 ](https://phabricator.wikimedia.org/T15387) SVG: Missing implementation for textLength
--- [T 193942](https://phabricator.wikimedia.org/T193942) fill using radialGradient not rendered
-- fixed in librsvg 2.50 (selection out of 27 tasks)
--- [T 217990](https://phabricator.wikimedia.org/T217990) arc flags without space
--- [T 276684](https://phabricator.wikimedia.org/T276684) direct clone of a clone not displayed
--- [T 32033 ](https://phabricator.wikimedia.org/T32033) stroke-dasharray in PNG thumbnails does not support spaces as separators
--- [T 207506](https://phabricator.wikimedia.org/T207506) librsvg does not shift from bold to normal font-weight
--- [T 246366](https://phabricator.wikimedia.org/T246366) update librsvg for correct dash-density
--- [T 7792 ](https://phabricator.wikimedia.org/T7792) rsvg does not render baseline-shift correctly (<percentage> and <length>)
--- [T 55899 ](https://phabricator.wikimedia.org/T55899) SVG masks fail to render (or even display)