W3C home > Mailing lists > Public > w3c-wai-ua@w3.org > January to March 2000

Rendered content vs source content.

From: Hans Riesebos <HRiesebos@alva-bv.nl>
Date: Fri, 25 Feb 2000 14:04:58 +0100
Message-Id: <s8b68c1c.069@mail.alva-bv.nl>
To: "<"<w3c-wai-ua@w3.org>
Rendered content vs source content.

I have been doing some thinking and in in my humble opinion I find the rendered content of real importance: Here are some reasons.

I believe MSAA gives you rendered content.

If the AT relies (sort of piggybags) on a UA one can assume the AT wants to make this UA accessible. Therefore the AT wants to be aware of the closed-loop interaction between User and UA of action and feedback. (What is the current point of regard, what is selected). To this purpose the AT needs to know about rendered content. 
The AT might want to control some of the rendering in order to get the information the UA-AT user wants. This could be done by controlling the UA and also by controlling style sheets. 
Without access to stylesheets I don't believe the AT can synchronise different output modalities. (I'm not sure of all the possibilities).

As said in the teleconference, the AT historically uses an Off Screen Model (OSM). The making of an OSM is difficult because it involves reverse engineering the rendering proces. The value of the DOM for the AT is that it does not need to reverse engineer rendering. However, if the AT has to work with the pure structured content without any rendering taken place, the AT needs to be able to render itself in order to obtain information on visibility, position, etc.. This seems redundant, because the UA it works with does the same rendering. 

Now what the UAGL currently says is that new/future AT is much helped with access to the DOM. I agree. But is seems unnatural for an AT to use a graphical desktop browser to provide an aural-only rendering of internet-content. It would seem natural for  an AT that wants graphical stuff to use a graphical desktop browser. In this last situation the UA does more service by providing rendered info to this AT. 

Concluding:
- To me it seems that the rendered sturcture is of real interest to the AT. 
- Access to stylesheets is priority one. 

Sincerely
Hans Riesebos
ALVA, The Netherlands
Received on Friday, 25 February 2000 08:04:21 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 27 October 2009 06:49:52 GMT