On 10/08/2009 20:27, rgheck wrote:
On 08/10/2009 02:03 PM, Manoj Rajagopalan wrote:
Thanks, Richard and Vincent.
For a long time I've wished for a LaTeX rendering widget in Qt. I do
a lot of
scientific computing and I'd like my GUI's to contain label widgets that
display greek symbols etc. and what better way to do this than to have a
constructor that interprets a subset of latex commands. Eg:
QLaTeXLabel *label = new QLaTeXLabel(this, QString("\frac{E}
{\hbar\omega}"));
I'm not sure, but I'd suspect that nothing like this is terribly
likely to come directly out of the LyX code.
Well, Manoj could also simply embed a LyX work area. He just need to
convert LyX into a library and use that. We have this nice sexy widget
called EmbeddedWorkArea which is pretty straight forward to use :-)
So Manoj, if you want to cleanup the source code a tiny bit so that we
could generate a LyX dll instead of the executable, you're basically
done. And you would be able to have a full blown LyX editor inside your app.
Math insets are complex entities. Each character is, in fact, in its
own inset; \frac generates an inset; so does \hbar. So there are
several insets buried in LyX's representation of that simple bit of
LaTeX. So this will get painted via a long recursion through various
things like InsetMathFrac::draw().
That said, what about doing something like instant preview? That would
give you a little picture.
Someone probably raised this issue a while ago on the LyX list and
one of the
developers replied that separating the lyx code to this would be a huge
amount of work. I've been spending some of my spare time
investigating if I
could do this. For this I need to know how 'commands' (or macros, lyx
parlance) are converted to glyphs which are rendered on the screen.
My guess is there should be a fontmap somewhere that maps latex
symbols to the
glyphs to be printed and this info should be read sometime after the
call to
Cursor::macroModeClose(). Latex has an elaborate font-map setup for
this.
Does LyX simply read the latex setup to infer this fontmap or does it
come
canned with its own map? Where is all this information initialized?
See the lib/symbols file. This maps things like \omega to a font (cmm)
and a codepoint, and does other stuff too. It gets read in the
initSymbols() routine in MathFactory.cpp.
That being said, if Manoj just want to display greek symbols, he can
just use unicode and a proper unicode fonts like the stix one. No need
for a LaTeX renderer...
Abdel.
