There are hundreds of icons in Tiki. Right now, jpeg/png/gif. The opportunity is to move them progressively to a vector format. This permits scaling, styling, saving bandwidth, etc.
There are 2 options: SVG vs fonts
It would be a shame to maintain both if there is one that could address the needs. It would be a shame to invest migration time in one of the solutions only to do the work in double later if a change is decided.
Feeling is that Tiki should pick the best future-thinking solution between SVG & fonts:
svg -> No Unnecessary HTTP Requests
I just started to look into the possibility to use .SVG instead of FONT and so far I did find a bunch of discussion WHY to use SVG or not to use SVG instead of FONT when it goes to vector-icons.
I have mainly heard about possible issues in respect of browser compatibility towards SVG, but I did NOT find ANY VG icon sets for possible integration (with a very limited! time on research).
At the bottom of the wiki page I added the licenses for the icon FONTs mentioned on the wiki page.
http://www.webhostinghub.com/glyphs shows an example how to possibly achieve switchable "icon-sets", as they use the Bootstrap Glyphicon-Halfling names for their icons.
Finally the PNG fallback seems to be already sorted in Tiki for FONT thanks to our Bootstrap activists.
For a convenient way of a PNG fallback for SVG I did not find further helpful information.
=> Conclusion=> In my mind, if no serious arguments will be brought up, the actual path to FONT seems the best to do.
In the end, when reviewing the licenses, I see only Fontawesome and Glyphicon-Halflings so far (both already implemented) and optionally Monosocialiconsfont as "add-on".
Use semantic names for icon names
Maybe based on names from here (removing "fa-" from the beginning): http://fontawesome.io/cheatsheet
Make it possible for themes to override icons
Questions looking for an answer:
Pick some preferred icon source(s) so community has guidelines for consistency and make sure licensing is OK
Have a Smarty function (or something) so vectorial is chosen if supported by the browser, and use png as a fallback
{glyph name="plus"} or {fa name="automobile"}
Also see https://dev.tiki.org/Icons