[BRLTTY] Brltty and the latex-access project

[Daniel Dalton]

On Fri, Jan 13, 2012 at 09:43:39PM -0500, Dave Mielke wrote:
> >latex-access still a problem, i.e. cursor routing data? I believe
> >getting a translation which was the desired length i.e. the same length
> >as the Braille display in use was still a bit of a problem? 
> 
> I'd stopped at the point where we needed to settle on a protocol for passing 
> data back and forth. It needs to support sending multiple values in both 
> directions. What do you think about sending a set of lines, each in the form 
> name=value, with a blank line at the end? So, for example, brltyt might send 
> something like this to your software:
> 
>    cursor=12
>    length=40

Hi, 

Sorry for the delay, I've been out of town for a few days and not the
kind of thing I can really study through email via android :)

That sounds ok as far as I can tell. 

How would the actual content be passed? i.e. the input line to the
latex-access translator and then of course output from the latex-access
translator to the display? 

What data does my project need to send to brltty? I suppose the updated
cursor position once cursor routing works... 
And brltty should tell latex-access the position of the cursor...?

Then would it be up to my project to provide brltty with a translation
of the desired length i.e. if the braille display is 40 cell then 40
Braille chars? 

>    text=   utf-8 encoded characters which can be indented and contain blanks

I really don't know much about uf8 to be honest... 

> 
> Output from your software back to brltty would be the same, but, of course, 
> with a different set of data. Is this approach okay?

Sounds pretty good to me. 

> We'd need to decide how to deal with newlines in the input text, as well as 
> with whatever braille dot combination looks like a newline in the output data.

MMMM. we didn't really have a translation for new line characters,
besides wouldn't this change across Braille codes, currently
latex-access is very stable with nemeth and relatively stable with ueb
though there are some fundimental  bugs. 

> We could always have a way for the output to say that BRF characters are being 
> used, which would support 6-dot braille and which wouldn't have a newline 
> problem.

Wouldn't the output always be brf output though if it was coming through
latex-access? 

To make what I'm saying clearer you can check out the code in svn at 
https://latex-access.svn.sourceforge.net/svnroot/latex-access

The testscript in the root directory should demonstrate how the latex is
converted to Braille. 

For instance you could do 

y = 2\sin(\frac{\pi}{2}x)+1
or 
x = \frac{-b\pm\sqrt{b^2-4ac}}{2a}

To get an idea of how the translation actually works. 

Thanks for your help,
Dan