code which determines object size in mPDF

sizes.php

<?php
// mpdf sizes code
// 
// extracted from mpdf itsel


//Scale factor
define('_MPDFK', (72 / 25.4));

class mpdf {
	
// this is only stub class, its not usable


function ConvertSize($size = 5, $maxsize = 0, $fontsize = false, $usefontsize = true)
	{
		// usefontsize - set false for e.g. margins - will ignore fontsize for % values
		// Depends of maxsize value to make % work properly. Usually maxsize == pagewidth
		// For text $maxsize = Fontsize
		// Setting e.g. margin % will use maxsize (pagewidth) and em will use fontsize
		// Returns values using 'mm' units
		$size = trim(strtolower($size));

		if ($size == 'thin')
			$size = 1 * (25.4 / $this->dpi); //1 pixel width for table borders
		elseif (stristr($size, 'px'))
			$size *= (25.4 / $this->dpi); //pixels
		elseif (stristr($size, 'cm'))
			$size *= 10; //centimeters
		elseif (stristr($size, 'mm'))
			$size += 0; //millimeters
		elseif (stristr($size, 'pt'))
			$size *= 25.4 / 72; //72 pts/inch
		elseif (stristr($size, 'rem')) {
			$size += 0; //make "0.83rem" become simply "0.83"
			$size *= ($this->default_font_size / _MPDFK);
		} elseif (stristr($size, 'em')) {
			$size += 0; //make "0.83em" become simply "0.83"
			if ($fontsize) {
				$size *= $fontsize;
			} else {
				$size *= $maxsize;
			}
		} elseif (stristr($size, '%')) {
			$size += 0; //make "90%" become simply "90"
			if ($fontsize && $usefontsize) {
				$size *= $fontsize / 100;
			} else {
				$size *= $maxsize / 100;
			}
		} elseif (stristr($size, 'in'))
			$size *= 25.4; //inches
		elseif (stristr($size, 'pc'))
			$size *= 38.1 / 9; //PostScript picas
		elseif (stristr($size, 'ex')) { // Approximates "ex" as half of font height
			$size += 0; //make "3.5ex" become simply "3.5"
			if ($fontsize) {
				$size *= $fontsize / 2;
			} else {
				$size *= $maxsize / 2;
			}
		} elseif ($size == 'medium')
			$size = 3 * (25.4 / $this->dpi); //3 pixel width for table borders
		elseif ($size == 'thick')
			$size = 5 * (25.4 / $this->dpi); //5 pixel width for table borders
		elseif ($size == 'xx-small') {
			if ($fontsize) {
				$size *= $fontsize * 0.7;
			} else {
				$size *= $maxsize * 0.7;
			}
		} elseif ($size == 'x-small') {
			if ($fontsize) {
				$size *= $fontsize * 0.77;
			} else {
				$size *= $maxsize * 0.77;
			}
		} elseif ($size == 'small') {
			if ($fontsize) {
				$size *= $fontsize * 0.86;
			} else {
				$size *= $maxsize * 0.86;
			}
		} elseif ($size == 'medium') {
			if ($fontsize) {
				$size *= $fontsize;
			} else {
				$size *= $maxsize;
			}
		} elseif ($size == 'large') {
			if ($fontsize) {
				$size *= $fontsize * 1.2;
			} else {
				$size *= $maxsize * 1.2;
			}
		} elseif ($size == 'x-large') {
			if ($fontsize) {
				$size *= $fontsize * 1.5;
			} else {
				$size *= $maxsize * 1.5;
			}
		} elseif ($size == 'xx-large') {
			if ($fontsize) {
				$size *= $fontsize * 2;
			} else {
				$size *= $maxsize * 2;
			}
		} else
			$size *= (25.4 / $this->dpi); //nothing == px

		return $size;
	}
  
  
}