Re: You Got Your SVG in my Canvas! Mmm, Delicious! (was: hit testing and retained graphics)

On Thu, Jun 30, 2011 at 11:39 AM, Richard Schwerdtfeger
<> wrote:
> "Tab Atkins Jr." <> wrote on 06/30/2011 12:53:34 PM:
>> Again, define your problems. Making your average game, such as the
>> ones produced by Zynga, accessible to the blind, for example, can
>> *not* be accomplished by exposing an alternate subtree. It can
>> theoretically be done, but only be exposing completely different
>> interaction modes, which are most likely fairly tightly coupled with
>> the design of the game itself. Different disabled subgroups require
>> different interaction modes.
> I am not trying to solve the gaming problem for the blind. And something you
> have a problem understanding is that the main problem we are solving is

How can I know you're not trying to solve that?  You haven't yet
stated what problem you're trying to solve, and you've talked about
Zynga's needs more than once.  It thus seems a natural assumption that
accessible gaming is a problem you want to solve.

>> There *are* accessibility problems that can be solved by exposing an
>> alternate subtree (or possibly by other solutions). Until you list
>> those problems, we have no way to tell how good your proposed solution
>> is.
> Alternative solutions depend on infinite number of problems and I am not
> inclined to boil an ocean with you.
> We are simply providing the ability to map visual objects and their
> relationships to platform accessibility API. New 508 government requirements
> in development require a whole littany of those. That is the problem we are
> trying to solve here. We are not trying to build new applications with
> different interaction models.

What. Problem. Are. You. Solving.

This question is both simple and vital.  There is no "simply
providing" on the web.  If your problem is "as quickly as possible,
make it possible for companies who chose to use the canvas 2d context
to comply with a particular set of US accessibility laws", then state
that.  I think it's a really bad problem to solve, but we can at least
debate that.

> I am not trying to solve accessible gaming but if I were a low vision user I
> would need to be able to find the damn object on the screen with their
> magnifier! It does not matter what the interaction model is. That would be
> like you trying to play Farmville on a 60 inch screen looking through a shot
> glass butted up against the screen. Try it some time and go find the shovel.

Being able to automatically magnify an active region of an application
is a useful problem to solve.  It is not solved very well by your
solution, as it only works when the app author goes to the extra
effort of annotating the canvas with information about what areas are
associated with certain elements in the alternative subtree.  Optional
APIs make for horrible accessibility in general, because most people
won't use them.


Received on Thursday, 30 June 2011 18:53:51 UTC