mouse-grid selection for navigation [was: Re: Updated SVG comments document]

At 1:25 PM -0600 11/24/04, Jon Gunderson wrote:
>I have updated the WAI SVG 1.2 comments document to add
>sections on benefits to people with disabilities. Comments or
>edits can be sent to the list.

I have some local-edit suggestions that I'll put in a following mail.

There is one issue that I consider major enough so that I don't want
to just slip it in or move ahead without giving the UAAG and PF
participants some opportunity to react.

This has to do with the keyboard navigation model for visual scenes.

There is a suggestion in the current draft for incremental navigation
by geometrical octants.  Comparable to the points of an eight-point
compass rose: North, North-East, East, etc.

But in voice command there is a precedent for another way of selecting
something in a scene without a pointing device.  This is I believe called
'mouse grid' in at least one tool.

The rectangular canvass is divided into [nine] equal parts.
The user selects one of these.
The selected part is subdiivided again into a similar set of sub-parts.
And so on until there is only one focusable item in the remaining
region.  This is not only selected but gets the focus.

The user can then activate the methods of this object.

To my way of thinking this is a mode of operation that belongs ahead
of any incremental navigation by quadrants as something for the
mainstream players to support for all users (not relying on AT add-ons)
as a means of ensuring access.

It affords a systematic way to reach any 'enabled element' to use the
UAAG term.  And it builds a breadcrumb trail that one can understand
without seeing the visual display.

It is definitely quicker with vision, but it has the advantage over incremental
navigation by quadrants in that it provides a comprehensible way to
sweep through all enabled elements in the scene by parts.

Think of this as a repair structure for a scene constructed with no marked
or discernable structure.


Did the User Agent group consider this functionality and reject it for some

Should we add this as an option or another suggestion alongside incremental
navigation by quadrants?

[Note: there is [four?] directional navigation to author-designated elements in
CSS for the TV delivery context.  What we actually do in SVG should make
sense as compared to the way that works, even if not identical.]

>Jon Gunderson, Ph.D., ATP
>Coordinator of Assistive Communication and Information Technology
>Division of Rehabilitation - Education Services
>College of Applied Life Studies
>University of Illinois at Urbana/Champaign
>1207 S. Oak Street, Champaign, IL  61820
>Voice: (217) 244-5870
>Fax: (217) 333-0248

Received on Monday, 29 November 2004 18:09:48 UTC