Re: implementations

Your proposal seems reasonable.

Things could get tricky when you take into consideration that two rendering engines--and other open-source projects--can start as forks from a common code base, but diverge over time. For example, way back in 2002 KTHML spawned the WebKit fork, which itself just spawned the Blink fork; have they all diverged sufficiently that we can consider them separate implementations? Is that true even for features that were implemented in KHTML and just inherited by the others?

Similarly, would outdated products also count as valid implementations, since they demonstrated the feature had been implemented in the real world? What about engines developed solely as research projects?

There are a few other HTML/XML layout engines listed at http://en.wikipedia.org/wiki/List_of_layout_engines.

     Greg

-------- Original Message --------
Subject: implementations
From: Jim Allan <jimallan@tsbvi.edu>
To: WAI-ua <w3c-wai-ua@w3.org>
Date: 11/12/2013 8:02 PM
>
> Yesterday during the meeting we found two implementations for 1.8.10 IE and QQ. Both use the same rendering/UI engine...IE. Judy wondered if that was really 2 implementations. I queried several folks about this issue. Ultimately, it is the working group that defines the implementation rules, but we will have to defend them to the director. The consensus was that we ought to have implementations from at least 2 different rendering engines for each SC. Additionally, I checked around with people who know engines...and mobile engines are substantially the same as the desktop engines. I think we need to have a discussion about this topic, and determine our rules for determining valid implementations.
> I propose that for each SC we have implementations from 2 different rendering engines. If we find more (other engine or mobile version) so much the better. I think this would work for SCs pertaining to content. I am checking on the the User Interface of the browsers. Are the user interface of browsers with the same rendering engine different code bases or just skins? How do we find out? If the user interface code is unique to the browser then I think we could have 2 different implementations from different browser with the same rendering engine. But, only for SCs pertaining to UI components (e.g. preference settings).
>
> Rendering Engines
> Gecko
> IE - Trident
> Blink
> Webkit
> Presto (opera) - in maintenance mode but still out there.
>
> also, found UC Browser (400 million mobile users) java only mobile browser on all platforms (except Apple), based on webkit.
> http://en.wikipedia.org/wiki/UC_Browser
> http://www.ucweb.com/English/UCMobileCompany/about.html
> -- 
> Jim Allan, Accessibility Coordinator & Webmaster
> Texas School for the Blind and Visually Impaired
> 1100 W. 45th St., Austin, Texas 78756
> voice 512.206.9315 fax: 512.206.9264 http://www.tsbvi.edu/
> "We shape our tools and thereafter our tools shape us." McLuhan, 1964
>