Re: Appendix E.2 and E.4

I have incorporated Stuart updates  in the Appendix.
http://www.w3.org/Graphics/WebCGM/WG/2006/wai-appendix-V2.html

I will send it to the WAI PF people for review.


Galt, Stuart A wrote:
> Hello all,
>  
> Lofton and I have spoken and feel that the following meets the action 
> item to reword sections E.2 and E.4  If there are no objections we will 
> forward the changes Monday to support the WAI face to face meeting.
>  
> Thank you for your time.
>  
> Stuart Galt.
>  
>  
> 
> --
> Stuart Galt
> SGML Resource Group
> stuart.a.galt@boeing.com
> (206) 544-3656
> 
> 
>     E.2 Navigation
> 
> By Guideline 9 "Provide navigation mechanisms" of [UAAG10 
> <http://www.w3.org/TR/2002/REC-UAAG10-20021217/>] a WebCGM viewer is 
> expected to let users interact with 'enabled' and significant objects in 
> the image.  'Enabled' objects are those which accept user input, such as 
> on screen buttons.  By the structure of WebCGM, each APS should be 
> treated as a significant object and be reachable by navigation 
> techniques.  By Guideline 1 "Support input and output device 
> independence" the reach of keyboard-actuated navigation should cover 
> this whole set of navigation destinations.
> 
> Some notion of forward and backward motion among peer nodes in the 
> WebCGM image should be provided.  This should by default move among 
> paragraphs and sub-paragraphs in the order in which they appear in the 
> metafile.  The creators of WebCGM instances should ensure that this 
> results in a sensible reading order.  However, efficient motion as 
> called for in [UAAG10] Checkpoint 9.9 
> <http://www.w3.org/TR/WAI-USERAGENT/guidelines.html#tech-nav-structure>, 
> is not likely to result from one global list or loop of all the 
> plausible navigation destinations.  Exploiting the structure of the 
> metafile, structured navigation could take hierarchical or categorical 
> forms.  In hierarchical navigation, forward and back motion moves among 
> peer nodes at the same level in the layers-and-objects nesting tree.  In 
> categorical navigation, the sequential navigation could exhibit 
> navigation modes which visit only 'grobject' nodes, or only the 
> 'gropbject' nodes with a common 'name.'  An example of hierarchical 
> navigation is provided by the player behavior for the [DAISY] standard 
> digital talking book.  An example of categorical structured navigation 
> is provided by the diverse navigation modes of the Opera browser.  The 
> creators of WebCGM instances should ensure that the layers-and-objects 
> nesting forms a plausible table of contents as annotated with the 
> textual properties (see E.3 below) of the affected nodes, and that 
> collecting nodes of like 'name' forms meaningful slices of what is in 
> the scene.
> 
> In this version of WebCGM, there are no intra-metafile controls to alter 
> the navigation graph. In a scenario where such capability is desired, 
> the private-namespace extension feature 
> <http://www.w3.org/TR/webcgm20/WebCGM20-XCF.html#extending> of the XCF 
> can be used to introduce further intelligence associated with the 
> contents of the metafile proper.
> 
>  ...
> 
>  
> 
> 
>     E.4 Visibility and Navigation
> 
> By default, WebCGM viewers allow the user to navigate to and interact 
> with only enabled elements (i.e. element whose 'visibility 
> <http://www.w3.org/TR/webcgm20/WebCGM20-IC.html#webcgm_visibility>' 
> attribute is 'on'). Objects which are not visible do not display 
> tooltips (the 'screentip' APS attribute), may not be highlighted without 
> making them visible, and may not be navigated to via the picture 
> behaviors (whether in picture fragments or DOM src parameter).
> 
> In addition, WebCGM viewers can offer a mode where, at user option, the 
> 'visibility 
> <http://www.w3.org/TR/webcgm20/WebCGM20-IC.html#webcgm_visibility>' 
> attribute is ignored, for accessibility or debugging support. It meets a 
> requirement of [UAAG10] <http://www.w3.org/TR/UAAG10/guidelines.html> 
> CheckPoint 9.3.
> 
>  
> 
> 
> 
>  


-- 
Thierry Michel
W3C

Received on Monday, 18 September 2006 08:34:20 UTC