GetMultiCellHeight() script for FPDF

gistfile1.php

function GetMultiCellHeight($w, $h, $txt, $border=null, $align='J') {
	// Calculate MultiCell with automatic or explicit line breaks height
	// $border is un-used, but I kept it in the parameters to keep the call
	//   to this function consistent with MultiCell()
	$cw = &$this->CurrentFont['cw'];
	if($w==0)
		$w = $this->w-$this->rMargin-$this->x;
	$wmax = ($w-2*$this->cMargin)*1000/$this->FontSize;
	$s = str_replace("\r",'',$txt);
	$nb = strlen($s);
	if($nb>0 && $s[$nb-1]=="\n")
		$nb--;
	$sep = -1;
	$i = 0;
	$j = 0;
	$l = 0;
	$ns = 0;
	$height = 0;
	while($i<$nb)
	{
		// Get next character
		$c = $s[$i];
		if($c=="\n")
		{
			// Explicit line break
			if($this->ws>0)
			{
				$this->ws = 0;
				$this->_out('0 Tw');
			}
			//Increase Height
			$height += $h;
			$i++;
			$sep = -1;
			$j = $i;
			$l = 0;
			$ns = 0;
			continue;
		}
		if($c==' ')
		{
			$sep = $i;
			$ls = $l;
			$ns++;
		}
		$l += $cw[$c];
		if($l>$wmax)
		{
			// Automatic line break
			if($sep==-1)
			{
				if($i==$j)
					$i++;
				if($this->ws>0)
				{
					$this->ws = 0;
					$this->_out('0 Tw');
				}
				//Increase Height
				$height += $h;
			}
			else
			{
				if($align=='J')
				{
					$this->ws = ($ns>1) ? ($wmax-$ls)/1000*$this->FontSize/($ns-1) : 0;
					$this->_out(sprintf('%.3F Tw',$this->ws*$this->k));
				}
				//Increase Height
				$height += $h;
				$i = $sep+1;
			}
			$sep = -1;
			$j = $i;
			$l = 0;
			$ns = 0;
		}
		else
			$i++;
	}
	// Last chunk
	if($this->ws>0)
	{
		$this->ws = 0;
		$this->_out('0 Tw');
	}
	//Increase Height
	$height += $h;

	return $height;
}

perfect and usefull !