On Sep 26, 2006, at 10:24 AM, Uwe Brauer wrote:
it is really a pity that there at least 3 programs floating around:
- Texvc - Blatex - WikitexTo return to my original question, can blahtex easily deal with numeration/references and labels?
No. It has no support. I don't plan any support either. The difficulty is the following: the way that image caching is designed in mediawiki, the PNG output must depend only on the input *for that single equation*. So for example, if you have a numbered equation, and then add another equation *before* that one, then the numbering on the later equation must change. This makes caching images much more difficult, because for example the input "x = y \label{eq:my- equation}" could correspond to two different images on two different pages. There are various ways you could get around this, but all would require a lot more work, and numerous changes to mediawiki itself which I'm not prepared to dive into.
Blahtex is designed to render one equation at a time, no more, no less. The problem of numbering equations is more a problem of *document markup*, which is a problem that should be solved by the enclosing document model, in this case mediawiki itself. I'm thinking something more like using <math label="abc">x = y</math> in the wikitext itself, and then <mathref>abc</mathref> later on to refer to it. This would be a much better solution, and would be completely independent of the mathematics rendering engine.
Perhaps Wikitex has worked out how to solve this problem.
Just from a pragmatic point of view, sites like
http://tosio.math.toronto.edu/wiki/index.php/Wave_equations
are very interested to include such a functionality.
I don't hope to start a flame war, but may be the authors of wikitex and blahtex could outline the differences of features of their programs? Or does such a comparison already exit?
I don't think there's any danger of a flame war... we're all reasonable people :-)
No-one has done a detailed comparison as far as I know. I haven't actually tried wikitex. From what I understand, it implements a much fuller subset of tex/latex than blahtex will ever do. From the beginning I wrote blahtex to use the same security model as texvc (i.e. whitelist a set of commands, fully parse the input before sending it off to tex/latex). Wikitex uses a different security model, it somehow allows much lower-level stuff through. I don't fully understand how they ensure this is a safe thing to do, although I believe they claim that it is safe, and I'm sure they can explain this in detail.
A consequence of Wikitex doing things at this lower level is that they can apparently use just about any latex package they like. Whereas blahtex needs to be told explicitly which commands to let through, and how to translate them to MathML.
Blahtex does MathML output, I don't think Wikitex does, but I could be mistaken. I think that when the STIX fonts are released, there will be a flurry of activity and MathML will soon become a much better way of distributing mathematics on the web than via PNG graphics. But that's still some time off. And even then, there are still plenty of things that can't be done with MathML (for example even simple commutative diagrams can be painful). Although I should point out that a committee was recently convened to start work on MathML 3.0, which may address some of these issues.
David