X-Git-Url: https://scripts.mit.edu/gitweb/autoinstallsdev/mediawiki.git/blobdiff_plain/a4b52d2fe555a507c376e78ee624898c55968364..d7967d5e4460e08b6b258307afbca0596b18a3dd:/math/README

diff --git a/math/README b/math/README
index 1349b83e..818ce6bd 100644
--- a/math/README
+++ b/math/README
@@ -1,7 +1,7 @@
 == About texvc ==
 
 texvc takes LaTeX-compatible equations and produces formatted output in
-HTML, MathML, and (via LaTeX/dvips/ImageMagick) rasterized PNG images.
+HTML, MathML, and (via LaTeX/dvipng) rasterized PNG images.
 Input data is parsed and scrutinized for safety, and the output includes
 an estimate of whether the code is simple enough that HTML rendering will
 look acceptable.
@@ -21,8 +21,13 @@ from http://caml.inria.fr/ if your system doesn't have it available.
 
 The makefile requires GNU make.
 
-Rasterization is done via LaTeX, dvips, and ImageMagick. These need
-to be installed and in the PATH: latex, dvips, convert
+Rasterization is done via LaTeX, dvipng. These need
+to be installed and in the PATH: latex, dvipng
+
+AMS* packages for LaTeX also need to be installed. Without AMS* some
+equations will render correctly while others won't render.
+Most distributions of TeX already contain AMS*.
+In Debian/Ubuntu you need to install tetex-extra.
 
 To work properly with rendering non-ASCII Unicode characters, a
 supplemental TeX package is needed (cjk-latex in Debian)
@@ -92,6 +97,15 @@ Ensure that the temporary and math directories exist and can be written to by
 the user account the web server runs under; if you don't control the server,
 you may have to make them world-writable.
 
+If some equations render correctly while others don't, you probably don't have
+AMS* packages for LaTeX installed. Most distributions of TeX come with AMS*.
+In Debian/Ubuntu AMS* is in tetex-extra package.
+To check if that is the problem you can try those two equations:
+    x + y
+    x \implies y
+The first uses only standard LaTeX, while the second uses symbol \implies from AMS*.
+If the first renders, but the second doesn't, you need to install AMS*.
+
 == Hacking ==
 
 Before you start hacking on the math package its good to know the workflow,
@@ -101,7 +115,6 @@ which is basically:
 2. texvc does its magic, which is basically to check for invalid latex code.
 3. texvc takes the user input if valid and creates a latex file containing it, see
    get_preface in texutil.ml
-4. latex(1) gets called to create a .dvi file, the a .ps file is created from the
-   .dvi file using dvips(1), and finally convert(1) creates a .png file from
-   the .ps file. See render.ml for this process (commenting out the removal of
+4. dvipng(1) gets called to create a .png file
+   See render.ml for this process (commenting out the removal of
    the temporary file is useful for debugging).