Re: [ui-dev] Q: How to implement XAccessibleText interface in formula editor ?

[Michael Brauer <michael brauer sun com>]

Hi Thomas,

Peter Korn wrote:

> Hi Thomas,


[...]


> I'm appending my person thoughts at the end of Thomas original e-mail
> below.


[...]

> I think for symbols like "%ALPHA", they should be seen as a single (Unicode
> or UTF8) character wherever possible.  Failing that, I think the characters
> of that "word" should share the same bounding rectangle.  But a single
> character would, I think, be better.


I agree to Peter. Whenever possible, we should put the UNICODE character 
code itself into the text instead of a symbolic name. For symbol names 
that map into the private UNICODE area, we might think of keeping the 
symbolic name and return the bounding box of the UNICODE character for 
all character posoitions of the symbolic name. However, any font might
contain characters in the private UNICODE area, therefor this is a 
general problem. For this reason, I would prefer to return the UNICODE 
character in any case.


> For more complex formulas, like a summation (or integral) from m to n, I
> think you'll have to pick a cannonical order (and it should be one we all
> agree to so it's standard throughout all accessible representations of math
> formulas).  We could also introduce a bunch of new AccessibleRelations to
> try to cover formulas, making each of these characters (or collections of
> characters) their own object with relations to other objects.
>
> Unfortunately, none of these approaches is really all that satisfying.
>
>
> A longer-term approach we should consider is finding a way to represent the
> entire formula as it's own object, and create an AccessibleDescription for
> the formula that explains what it is (so something like "Integral from m to
> n of the function f(x)").  Also, we should look toward standards like


In the long term, this seems to be a good approach. If we are lucky,
someone implements a component that genarates a desciption like this out
of Math ML ...

In the short term we could put the formula text itself into the 
description, maybe omitting the '%' signs in front of symbolic names.


> MathML to represent the formulas, and expose the MathML directly for a
> screen access product to parse as it chooses.  If there is a MIME type for
> MathML, we could use the AccessibleStreamable interface (in GNOME, not yet
> in the Java Accessibility API) to indicate there is a MathML stream which
> can be parsed for this object.


In fact OOo Math is able to read and write Math ML. Therefor we should 
keep this is mind.


> Regards,
>
> Peter Korn
> Sun Accessibility team


Regards


Michael