"$$(a + b)^2 = a^2 + 2 ab + b^2$$"); } function parseArgStr($argstr) { // modified from WikiPlugin.php $arg_p = '\w+'; $op_p = '(?:\|\|)?='; $word_p = '\S+'; $opt_ws = '\s*'; $qq_p = '" ( (?:[^"\\\\]|\\\\.)* ) "'; //"<--kludge for brain-dead syntax coloring $q_p = "' ( (?:[^'\\\\]|\\\\.)* ) '"; $gt_p = "_\\( $opt_ws $qq_p $opt_ws \\)"; $argspec_p = "($arg_p) $opt_ws ($op_p) $opt_ws (?: $qq_p|$q_p|$gt_p|($word_p))"; $args = array(); $defaults = array(); while (preg_match("/^$opt_ws $argspec_p $opt_ws/x", $argstr, $m)) { @ list(,$arg,$op,$qq_val,$q_val,$gt_val,$word_val) = $m; $argstr = substr($argstr, strlen($m[0])); // Remove quotes from string values. if ($qq_val) // we don't remove backslashes in tex formulas // $val = stripslashes($qq_val); $val = $qq_val; elseif ($q_val) $val = stripslashes($q_val); elseif ($gt_val) $val = _(stripslashes($gt_val)); else $val = $word_val; if ($op == '=') { $args[$arg] = $val; } else { // NOTE: This does work for multiple args. Use the // separator character defined in your webserver // configuration, usually & or & (See // http://www.htmlhelp.com/faq/cgifaq.4.html) // e.g. // url: RecentChanges?days=1&show_all=1&show_minor=0 assert($op == '||='); $defaults[$arg] = $val; } } if ($argstr) { $this->handle_plugin_args_cruft($argstr, $args); } return array($args, $defaults); } function createTexFile($texfile, $text) { // this is the small latex file // which contains only the mathematical // expression $fp = fopen($texfile, 'w'); $str = "\documentclass{article}\n"; $str .= "\usepackage{amsfonts}\n"; $str .= "\usepackage{amssymb}\n"; // Here tou can add some package in order // to produce more sophisticated output $str .= "\pagestyle{empty}\n"; $str .= "\begin{document}\n"; $str .= $text . "\n"; $str .= "\end{document}"; fwrite($fp, $str); fclose($fp); return 0; } function createPngFile($imagepath, $imagename) { // to create dvi file from the latex file $commandes = $this->latexbin . " temp.tex;"; exec("cd $imagepath;$commandes"); // to create png file from the dvi file // there is no option but it is possible // to add one (scale for example) if (file_exists("$imagepath/temp.dvi")){ $commandes = $this->dvipsbin . " temp.dvi -o temp.ps;"; $commandes .= $this->pstoimgbin . " -type png -margins 0,0 "; $commandes .= "-crop a -geometry 600x300 "; $commandes .= "-aaliastext -color 1 -scale 1.5 "; $commandes .= "temp.ps -o " . $imagename; exec("cd $imagepath;$commandes"); unlink("$imagepath/temp.dvi"); unlink("$imagepath/temp.ps"); } else echo _(" (syntax error for latex) "); // to clean the directory unlink("$imagepath/temp.tex"); unlink("$imagepath/temp.aux"); unlink("$imagepath/temp.log"); return 0; } function isMathExp(&$text) { // this function returns // 0 : text is too long or not a mathematical expression // 1 : text is $xxxxxx$ hence in line // 2 : text is $$xxxx$$ hence centered $last = strlen($text) - 1; if($last >= 250){ $text = "Too long !"; return 0; } elseif($last <= 1 || strpos($text, '$') != 0){ return 0; } elseif(strpos($text, '$', 1) == $last) return 1; elseif($last > 3 && strpos($text, '$', 1) == 1 && strpos($text, '$', 2) == $last - 1) return 2; return 0; } function tex2png($text) { // the name of the png cached file $imagename = md5($text) . ".png"; $url = $this->imagepath . "/$imagename"; if(!file_exists($url)){ if(is_writable($this->imagepath)){ $texfile = $this->imagepath . "/temp.tex"; $this->createTexFile($texfile, $text); $this->createPngFile($this->imagepath, $imagename); } else { $error_html = _("TeX imagepath not writable."); trigger_error($error_html, E_USER_NOTICE); } } // there is always something in the html page // even if the tex directory doesn't exist // or mathematical expression is wrong switch($this->isMathExp($text)) { case 0: // not a mathematical expression $html = HTML::tt(array('class'=>'tex', 'style'=>'color:red;'), $text); break; case 1: // an inlined mathematical expression $html = HTML::img(array('class'=>'tex', 'src' => $url, 'alt' => $text)); break; case 2: // mathematical expression on separate line $html = HTML::img(array('class'=>'tex', 'src' => $url, 'alt' => $text)); $html = HTML::div(array('align' => 'center'), $html); break; default: break; } return $html; } function run($dbi, $argstr, &$request, $basepage) { // from text2png.php if ((function_exists('ImageTypes') and (ImageTypes() & IMG_PNG)) or function_exists("ImagePNG")) { // we have gd & png so go ahead. extract($this->getArgs($argstr, $request)); return $this->tex2png($text); } else { // we don't have png and/or gd. $error_html = _("Sorry, this version of PHP cannot create PNG image files."); $link = "http://www.php.net/manual/pl/ref.image.php"; $error_html .= sprintf(_("See %s"), $link) ."."; trigger_error($error_html, E_USER_NOTICE); return; } } }; // $Log: not supported by cvs2svn $ // Revision 1.3 2004/11/01 10:43:59 rurban // seperate PassUser methods into seperate dir (memory usage) // fix WikiUser (old) overlarge data session // remove wikidb arg from various page class methods, use global ->_dbi instead // ... // // For emacs users // Local Variables: // mode: php // tab-width: 8 // c-basic-offset: 4 // c-hanging-comment-ender-p: nil // indent-tabs-mode: nil // End: ?>