math/README

   1 == About texvc ==
   2
   3 texvc takes LaTeX-compatible equations and produces formatted output in
   4 HTML, MathML, and (via LaTeX/dvips/ImageMagick) rasterized PNG images.
   5 Input data is parsed and scrutinized for safety, and the output includes
   6 an estimate of whether the code is simple enough that HTML rendering will
   7 look acceptable.
   8
   9 The program was written by Tomasz Wegrzanowski for use with MediaWiki;
  10 it's included as part of the MediaWiki package (http://wikipedia.sf.net)
  11 and is under the GPL license.
  12
  13 Please report bugs at: http://bugzilla.wikimedia.org/ (under "MediaWiki")
  14
  15 == Setup ==
  16
  17 === Requirements ===
  18
  19 OCaml 3.06 or later is required to compile texvc; this can be acquired
  20 from http://caml.inria.fr/ if your system doesn't have it available.
  21
  22 The makefile requires GNU make.
  23
  24 Rasterization is done via LaTeX, dvips, and ImageMagick. These need
  25 to be installed and in the PATH: latex, dvips, convert
  26
  27 To work properly with rendering non-ASCII Unicode characters, a
  28 supplemental TeX package is needed (cjk-latex in Debian)
  29
  30 === Installation ===
  31
  32 Run 'make' (or 'gmake' if GNU make is not your default make). This should
  33 produce the texvc executable.
  34
  35 If you're using MediaWiki's install.php and have enabled $wgUseTeX in your
  36 LocalSettings.php, the installer will try to copy texvc into place, in the
  37 'math' subdirectory under where wiki.phtml is installed.
  38
  39
  40 == Usage ==
  41
  42 Normally texvc is called from MediaWiki's Math.php modules and everything
  43 Just Works. It can be run manually for testing or for use in another app.
  44
  45 === Command-line parameters ===
  46
  47     texvc <temp directory> <output directory> <TeX code> <encoding>
  48
  49 Be sure to properly quote the TeX code!
  50
  51 Example:
  52
  53     texvc /home/wiki/tmp /home/wiki/math "y=x+2" iso-8859-1
  54
  55 === Output format ===
  56
  57 Status codes and HTML/MathML transformations are returned on stdout.
  58 A rasterized PNG file will be written to the output directory, named
  59 for the MD5 hash code.
  60
  61 texvc output format is like this:
  62     +%5         ok, but not html or mathml
  63     c%5%h       ok, conservative html, no mathml
  64     m%5%h       ok, moderate html, no mathml
  65     l%5%h       ok, liberal html, no mathml
  66     C%5%h\0%m   ok, conservative html, with mathml
  67     M%5%h\0%m   ok, moderate html, with mathml
  68     L%5%h\0%m   ok, liberal html, with mathml
  69     X%5%m       ok, no html, with mathml
  70     S           syntax error
  71     E           lexing error
  72     F%s         unknown function %s
  73     -           other error
  74
  75  \0 - null character
  76  %5 - md5, 32 hex characters
  77  %h - html code, without \0 characters
  78  %m - mathml code, without \0 characters
  79
  80
  81 == Troubleshooting ==
  82
  83 Unforunately, many error conditions with rasterization are not well reported.
  84 texvc will return as though everything is successful, and the only obvious
  85 sign of problems for the user is a big X on a wiki page where an equation
  86 should be.
  87
  88 Try running texvc from the command line to ensure that the software it relies
  89 upon is all set up.
  90
  91 Ensure that the temporary and math directories exist and can be written to by
  92 the user account the web server runs under; if you don't control the server,
  93 you may have to make them world-writable.
  94
  95 == Hacking ==
  96
  97 Before you start hacking on the math package its good to know the workflow,
  98 which is basically:
  99
 100 1. texvc gets called by includes/Math.php (check out the line begining with "$cmd")
 101 2. texvc does its magic, which is basically to check for invalid latex code.
 102 3. texvc takes the user input if valid and creates a latex file containing it, see
 103    get_preface in texutil.ml
 104 4. latex(1) gets called to create a .dvi file, the a .ps file is created from the
 105    .dvi file using dvips(1), and finally convert(1) creates a .png file from
 106    the .ps file. See render.ml for this process (commenting out the removal of
 107    the temporary file is useful for debugging).