filter/algebra/pix.php

   1 <?PHP // $Id$
   2       // This function fetches math. images from the data directory
   3       // If not, it obtains the corresponding TeX expression from the cache_tex db table
   4       // and uses mimeTeX to create the image file
   5
   6     $nomoodlecookie = true;     // Because it interferes with caching
   7
   8     require_once('../../config.php');
   9
  10     if (empty($CFG->textfilters)) {
  11         error ('Filter not enabled!');
  12     } else {
  13         $filters = explode(',', $CFG->textfilters);
  14         if (array_search('filter/algebra', $filters) === FALSE) {
  15             error ('Filter not enabled!');
  16         }
  17     }
  18
  19     // disable moodle specific debug messages
  20     disable_debugging();
  21
  22     require_once($CFG->libdir.'/filelib.php');
  23     require_once($CFG->dirroot.'/filter/tex/lib.php');
  24
  25     $cmd    = '';               // Initialise these variables
  26     $status = '';
  27
  28     //error_reporting(E_ALL);
  29
  30     $relativepath = get_file_argument('pix.php');
  31
  32     $args = explode('/', trim($relativepath, '/'));
  33
  34     if (count($args) == 1) {
  35         $image    = $args[0];
  36         $pathname = $CFG->dataroot.'/filter/algebra/'.$image;
  37     } else {
  38         error('No valid arguments supplied');
  39     }
  40
  41     if (!file_exists($pathname)) {
  42         $md5 = str_replace('.gif','',$image);
  43         if ($texcache = get_record('cache_filters', 'filter', 'algebra', 'md5key', $md5)) {
  44             if (!file_exists($CFG->dataroot.'/filter/algebra')) {
  45                 make_upload_directory('filter/algebra');
  46             }
  47
  48             $texexp = $texcache->rawtext;
  49             $texexp = str_replace('&lt;','<',$texexp);
  50             $texexp = str_replace('&gt;','>',$texexp);
  51             $texexp = preg_replace('!\r\n?!',' ',$texexp);
  52             $texexp = '\Large ' . $texexp;
  53             $cmd = tex_filter_get_cmd($pathname, $texexp);
  54             system($cmd, $status);
  55         }
  56     }
  57
  58     if (file_exists($pathname)) {
  59         send_file($pathname, $image);
  60     } else {
  61         if (debugging()) {
  62             echo "The shell command<br />$cmd<br />returned status = $status<br />\n";
  63             echo "Image not found!<br />";
  64             echo "Please try the <a href=\"$CFG->wwwroot/filter/algebra/algebradebug.php\">debugging script</a>";
  65         } else {
  66             echo "Image not found!<br />";
  67             echo "Please try the <a href=\"$CFG->wwwroot/filter/algebra/algebradebug.php\">debugging script</a><br />";
  68             echo "Please turn on debug mode in site configuration to see more info here.";
  69         }
  70     }
  71 ?>