/**
* Callback function for preg_replace_callback (LaTeX replacement).
* Returns replacement image for LaTeX code.
* @param $matches (string) array containing matches: $matches[0] is the complete match, $matches[1] the match for the first subpattern enclosed in '(...)' (the LaTeX code)
* @return string replacement HTML code string to include the equivalent LaTeX image.
*/
function F_latex_callback($matches)
{
require_once '../../shared/code/tce_latexrender.php';
$latex = new LatexRender();
$latex_code = unhtmlentities($matches[1]);
// get image URL
$imgurl = $latex->getFormulaURL($latex_code);
if ($imgurl) {
// alternative text to image
$alt_latex = '[LaTeX]' . "\n" . htmlentities($latex_code, ENT_QUOTES);
$alt_latex = str_replace("\r", ' ', $alt_latex);
$alt_latex = str_replace("\n", ' ', $alt_latex);
// XHTML code for image
$newtext = '<img src="' . $imgurl . '" alt="' . $alt_latex . '" class="tcecode" />';
} else {
$newtext = '[LaTeX: ERROR ' . $latex->getErrorCode() . ']';
}
return $newtext;
}
