[BRLTTY] BRLTTY and the latex-access project by means of python brlapi module

[Daniel Dalton]

Hi Dave, 

Just wondering if my last email covered all the information you
required?

Cheers, 
Dan

On Sun, Dec 04, 2011 at 01:32:52PM +1100, Daniel Dalton wrote:
> On Sat, Dec 03, 2011 at 11:21:52AM -0500, Dave Mielke wrote:
> > [quoted lines by Daniel Dalton on 2011/12/03 at 17:27 +1100]
> > 
> > >Actually, I'm not even certain that my code in
> > >/etc/brltty/nemeth_brltty.ctb is being ran even though it's
> > >executable. I made it write some text to a file, and it works when I
> > >invoke it manually, but nothing happens when I run brltty... 
> > >i.e. the file is not created.
> > 
> > Yes, that'd be correct. Perhaps I hadn't made it clear enough that I was 
> > proposing a new capability. I didn't start implementing it right away as I 
> > wasn't sure if you were going to find it useful.
> 
> Sorry, my mistake. 
> 
> > I can start implementing it right now if you wish? Would you mind sending me a 
> > copy of your code, along with a file contianing a few actual latex samples, so 
> > that I can have something real to work with? I can fake it, of course, but it's 
> > much more fun working with a real application.
> 
> Certainly. The code is available via svn, the url is:
> https://latex-access.svn.sourceforge.net/svnroot/latex-access
> 
> I am also attaching the code I listed in one of my earlier emails to
> receive the input from stdin and output to stdout, but it correctly
> determines what table to use from our latex-access project. Actually,
> I'll include it in svn, it's called latex-access-brltty.ctb.
> 
> The various .py and .table files in the root directory of the svn
> checkout need to either be coppied to some directory in the python path
> or alternatively, and probably much easier (it's what I do), would just
> be to append the latex-access checkout directory to the python path. I
> suppose the various files like settings.py and ueb.py should probably be
> renamed to latex_access_settings.py and latex_access_ueb.py, but that's
> something I can do later anyway. 
> 
> The settings are usually stored in ~/.latex-access, but working with the
> default settings, in this case nemeth will be sufficient for our
> purposes. 
> 
> I've also attached some sample latex for you. 
> 
> > One of the things brltty supports is being able to map a position in the 
> > contracted text back to its positioin in the original text. Is your code able 
> > to provide this data? If not, how hard would it be to add?
> 
> Unfortunately, not at the present time, although it's something I've
> been looking to implement. Unfortunately, it will be quite difficult
> from what I can see given we have many functions which handle different
> latex markup. I have a few ideas though, and shall write to the other
> developers to see how they feel about doing this. So for now,
> unfortunately cursor routing wouldn't work but it is something I'll
> probably be looking to do once I get this up and running. 
> 
> What would the best way to store the latex position and it's
> corresponding Braille position be? 
> 
> Could I have a list where each index number corresponds to the Braille
> chars, i.e. list[0] = the first braille char, and the value of each
> index represents the corresponding character in the LaTeX? 
> 
> I suppose I'd also need to figure out a good way of expanding the text
> under the cursor as well. Do you think it would be best to expand the Braille
> symbol under the cursor in all cases, for editing purposes, I believe
> this is how brltty contraction tables work anyway...
> 
> > Did I understand correctly that your code currently uses the BRF format, i.e. 
> > the characters within the range 0X20-0X5F, to represent what each cedll should 
> > contain?
> 
> Yes, I believe so. You can also experiment with the test script provided
> in the root directory for nemeth only, but that should show you how it
> works. 
> It looks like brf to me anyway. 
> 
> Finally, you might notice the file brltty.py in the root directory; that
> is my implementation of Braille via brltty which works ok, but I haven't
> done key bindings yet, but I believe that this implementation should
> work much better, and that stuff will be removed once we can do the
> convertion via brltty contraction tables. 
> 
> Thanks very much,
> Dan

> \documentclass[12pt,a4paper]{article}
> \usepackage[pdftex]{hyperref}
> \usepackage{tabularx}
> \usepackage{graphicx}
> \usepackage{float}
> \usepackage{amsmath}
> \usepackage{amssymb}
> \usepackage{sistyle}
> \usepackage{gensymb}
> \usepackage{datetime}
> \newdateformat{auDateFormat}{%
>   \twodigit{\THEDAY}~\monthname[\THEMONTH]~\THEYEAR
> }
> \auDateFormat
> 
> \begin{document}
> \title{Sample LaTeX}
> \author{Daniel Dalton}
> \maketitle
> $3x+12 = 15$
> 
> $\beta$
> 
> $a=\pi r^{2}$
> 
> $v = f\lambda$
> 
> \begin{align*}
>   y &= x^{2}+6x+14
> \end{align*}
> 
> \begin{align*}
>   x &= \frac{-b\pm\sqrt{b^{2}-4ac}}{2a}\\
>   &= \frac{-6\pm\sqrt{6^{2}-4(1)(14)}}{2(1)}\\
>   &= \frac{-6\pm\sqrt{36-56}}{2}\\
>   &= \frac{-6\pm\sqrt{-20}}{2}\\
>   &= \text{No real solution}
> \end{align*}
> 
> $e_{xray} = 1.6\times10^{-19}f$
> 
> $x^{2} \le 0$
> 
> $\frac{3}{2}$
> 
> \end{document}