What I described whould not need to all happen at once. The common text
format may initially only be used for UEB, but over time may be the
other codes could be moved to it as well.
As an example take a fraction. In Nemeth.sem the third column is ^?,/^#
and in ukmaths.sem the third column is \x0003,@456-34,\x0004.
My thought is that for the three parts of a fraction we may define the
following private unicode characters:
* u+e002 Start fraction
* u+e003 over indicator.
* u+e004 end fraction
Then in the math.sem file the third column would be
\xe002,\xe003,\xe004. The UEB tables from the start may be designed to
work with these and then over time the nemeth table could be altered to
stop looking for ^? and look for \xe002 instead. Likewise with the
ukmaths.sem file.
Admittedly fractions may be a simple case and may be I will hit problems
later on. I have not yet investigated UEB enough to be certain with UEB,
but looking at the three maths codes' .sem files in LibLouisUTDML, this
all looks very doable and not too complicated and I don't foresee issues
with those.
My thought in doing this is that if there is a common text language for
communicating maths to LibLouis then this could be used by any software
wanting to do math translation, regardless of the source format. Under
the current situation the software would need to do different stuff
depending on the Braille code it wants out and seems like a lot of work.
As we are needing to do math translation without LibLouisUTDML already
in APH, I feel the work in doing this common text format will be no
more, possibly less, than doing the other options available.
Related to this, I am planning to use the private use area between
u+e000 and u+f8ff. My thought with this is that then it will be
available regardless of LibLouis being compiled with UCS2 or UCS4. Does
anyone see an issue with this, might there be other private use
standards we may want to use within this range?
Michael Whapples
On 14/04/2016 11:39, John J. Boyer wrote:
Hi Michael,
A common linear text for the different mathematical codes is certainly
possible. The Nemeth .sem file and liblouis tables were developed first
and were prodeucing very good results. I didn't want to monkey with
them. It was safer to take a fresh approach with UKMaths. Keith says
that UEB math can be handled by liblouis by adding it to the UEB tables.
Of course, the MathML has to be handled by something else.
I'm not sure that developing a single text string to replace the
existing .sem files is a good use of your time.
John
On Thu, Apr 14, 2016 at 10:34:08AM +0100, Michael Whapples wrote:
Thanks for that. It is always best to check if people previously hit issues
when trying to do something similar.
Having worked through the .sem files, I feel that at least for the three
already in LibLouis that a common text format could be created. I am
thinking of possibly using the private use unicode block.
Whilst it probably will be heavily influenced by the LibLouisUTDML existing
.sem files, the private use character assignments probably will more relate
to semantic meaning (eg. begin fraction, end fraction, begin table cell,
etc) rather than just getting the correct Braille (I noticed a number of
things in the .sem files where the Braille was the same but it meant
something different). My thought being that the LibLouis table can always
translate the different characters into the same dot pattern.
My thought with this is that the processing of the MathML can be done in one
way regardless of the Braille code and the Braille code is only determined
by the LibLouis table used. In LibLouisUTDML terms this would mean a single
math.sem file and the liblouis tables are what give you UEB, Nemeth, UK
maths or Marburg.
The main risk I see is that in focusing on the four Braille codes I mention
above that if someone tries to add another math Braille code then may be the
text format will not quite be sufficient. Hopefully in such a case it would
be possible to add additional character assignments to maintain the
information needed and the four existing codes can just ignore those
additional characters. There is a risk of a Braille code being laid out in a
different way and so needing different semantic action files. This I think
is a risk I am prepared to take, we could get stuck considering the problem
too much and not getting anything done and it might be questionable whether
for something differing so much whether a common text format could even be
achieved.
Michael Whapples
On 14/04/2016 01:09, John J. Boyer wrote:
The reason the nemeth.sem and the ukmaths.sem files are so diffieent isFor a description of the software, to download it and links to
that i learned as i developed. By the time the UKMaths was needed i had
realized that it would be much better to use dot patterns. There was
never a question of a common linear text. UKMath required a lot of
additional code. It was much more difficult to handle than Nemeth.
John
On Wed, Apr 13, 2016 at 02:35:32PM +0100, Michael Whapples wrote:
As Keith mentioned APH are looking at UEB math in BrailleBlaster, but this
won't be through LibLouisUTDML.
Regarding LibLouisUTDML, I have some questions for John. I notice that the
Nemeth.sem file has some sort of escape sequences, based on the Nemeth
symbols. In contrast the UK Maths and Marburg files seem to do a lot more by
using the dot patterns. I know that the Nemeth.sem file was developed first
with the other two coming later and may be from other contributors.
However this raises the question why a common linear text format was not
used? Looking at the .sem files other than the third columns these seems to
basically be the same, which to me implies what is passed to liblouis is
structurally the same. What I am trying to get at, was there a technical
reason why a common linear text format was not used for all three or is it
more to do with them being developed at different times and never quite
getting to it.
Michael Whapples
On 13/04/2016 07:10, John J. Boyer wrote:
I don't know if anyone is working on UEB math. However, UKMaths andFor a description of the software, to download it and links to
Marburg maths are already supported. UEB maths should not be a big
problem.
John
On Wed, Apr 13, 2016 at 04:28:21AM +0100, tolga karatas wrote:
--
many thanks,
tolga
Dear Sir/madam;
I am a blind/visually impaired student studying a degree in computing;
I am using the focus 40 braille display;
I was wondering when UEB maths support is going to be available please?
Yours Faithfully;
Tolga Karatas
For a description of the software, to download it and links to
project pages go to http://liblouis.org
project pages go to http://liblouis.org
project pages go to http://liblouis.org
