Re: feedback requested: Canvas change for improved hit testing that also facilitates accessibility

(We were recently requested not to cross-post to multiple HTML working 
group mailing lists but I wasn't sure which mailing list to leave so I 
just left the main one. Feel free to forward this to other groups if I am 
mistaken in this.)

On Wed, 30 Mar 2011, Richard Schwerdtfeger wrote:
> It is an attempt to simplify hit testing in canvas while at the same 
> time providing a vehicle to tell an assistive technology the bounds of 
> the corresponding UI object being drawn on canvas as represented in 
> fallback content.

FWIW the long-term plan for canvas is to introduce a Path primitive that 
can be used for, amongst other things, trivial hit-testing.

It's not clear to me why an AT needs to know the bounds of non-focused 
elements, or indeed how that would work given a canvas where widgets are 
continuously moving or resizing, or where widgets don't really have a 
concrete dimension until they are being interacted with, but maybe the 
best way to progress with that would be to build a small collection of 
concrete testable examples showing how one is envisaging the canvas API 
being used so that we can make sure we are addressing real use cases (and 
to make sure we agree on what the use cases are).

Ian Hickson               U+1047E                )\._.,--....,'``.    fL       U+263A                /,   _.. \   _\  ;`._ ,.
Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'

Received on Wednesday, 30 March 2011 21:45:09 UTC