Render Formula

Here is my 4th Code:
By this class you can render your math formula:

<?phpclass formel {	var $functionNames = array("WURZEL","sin","cos","pow","ARCSIN");	var $ttf;	var $ttfFile;		function formel() {		// {{{		$this->ttf = false;		$this->ttfSize = 15;		// }}}	}		function useTTF($ttfFile) {		// {{{		$this->ttf = true;		$this->ttfFile = $ttfFile;		// }}}	}		function parse($f) {		// {{{		$f = str_replace(" ","",$f);		$i = 0;		while($i<strlen($f)) {						do {				$c = substr($f,$i,1);				if($c==" ") $i++;			} while($c==" ");			//echo $c."<br>";						$functionName = "";						for($j=0;$j<count($this->functionNames);$j++) {				if(strtoupper(substr($f,$i,strlen($this->functionNames[$j]))) == strtoupper($this->functionNames[$j])) {					$i += strlen($this->functionNames[$j]);					$c = substr($f,$i,1);					$functionName = strtoupper($this->functionNames[$j]);					//echo $c."<br>";					//exit;				}			}									if($c=="+") {				if($nr!="") $Z[] = array("type"=>"number", "value"=>$nr);				$Z[] = array("type"=>"+", "value"=>"+");				$nr="";			} else if($c=="-") {				if($nr!="") $Z[] = array("type"=>"number", "value"=>$nr);				$Z[] = array("type"=>"-", "value"=>"-");				$nr="";			} else if($c=="=") {				if($nr!="") $Z[] = array("type"=>"number", "value"=>$nr);				$Z[] = array("type"=>"=", "value"=>"=");				$nr="";			} else if($c=="*") {				if($nr!="") $Z[] = array("type"=>"number", "value"=>$nr);				$Z[] = array("type"=>"*", "value"=>"*");				$nr="";			} else if($c=="/") {				if($nr!="") $Z[] = array("type"=>"number", "value"=>$nr);				$Z[] = array("type"=>"/", "value"=>"/");				$nr="";			} else if($c=="^") {				if($nr!="") $Z[] = array("type"=>"number", "value"=>$nr);				$Z[] = array("type"=>"^", "value"=>"^");				$nr="";			} else if($c=="(") {				$klammer = 1;				$f2 = "";				while($i<strlen($f)) {					$i++;					$c = substr($f,$i,1);					if($c=="(") $klammer++;					if($c==")") {						$klammer--;						if($klammer==0) {							//echo "<b>".$f2."</b><br>";							$D = array("type"=>"klammer");							if($functionName!="") $D["function"] = $functionName;							$D["value"] = $this->parse($f2);							$Z[] = $D;							break;						} else $f2 .= $c;					} else {						$f2 .= $c;					}				}			} else {				$nr .= $c;			}									$i++;		}		if($nr!="") $Z[] = array("type"=>"number", "value"=>$nr);		return($Z);		// }}}	}		function parse2($Z, $reparse=true) {		// {{{		$Z2 = array();		for($i=0;$i<count($Z);$i++) {			// {{{						$wert = $Z[$i];			if($wert["type"]=="-" || $wert["type"]=="+" || $wert["type"]=="=") {				$vorzeichen = $wert["type"];				$i++;				$wert = $Z[$i];				if($vorzeichen=="-") $wert["value"] = "-".$wert["value"];			}			if($wert["type"]=="klammer") {				$wert["value"] = $this->parse2($wert["value"]);			}						if($i+1>=count($Z)) {				$Z2[] = $wert;				break;			}			if($Z[$i+1]["type"]=="+" || $Z[$i+1]["type"]=="-" || $Z[$i+1]["type"]=="=") {				$Z2[] = $wert;				$Z2[] = $Z[$i+1];				$i++;			} else if($Z[$i+1]["type"]=="^") {				$K = array();				$K[] = $wert;				$i++;				$K[] = $Z[$i];				$i++;				$W = $Z[$i];				if($W["type"]=="klammer") {					$W["value"] = $this->parse2($W["value"]);				}				$K[] = $W;				$Z2[] = array("type"=>"klammer", "potenz"=>true, "value" => $K);								if($i+1<count($Z)) {					$i++;					$Z2[] = $Z[$i]; 				}							} else if($Z[$i+1]["type"]=="*" || $Z[$i+1]["type"]=="/") {				$K = array();				$K[] = $wert;				$i++;								if($Z[$i]["type"]=="/") {					// {{{					$K[] = $Z[$i];					$i++;					$W = $Z[$i];					if($W["type"]=="klammer") {						$W["value"] = $this->parse2($W["value"]);					}					$K[] = $W;					$i++;					$K2 = array("type"=>"klammer", "division"=>true, "value" => $K );					$K = array($K2);					// }}}				} 								while($i<count($Z)) {					if($Z[$i]["type"]!="+" && $Z[$i]["type"]!="-" && $Z[$i]["type"]!="=") {						if($Z[$i]["type"]=="/") {														$K2 = array($K[count($K)-1]);							$K2[] = $Z[$i];							$i++;							$W = $Z[$i];							if($W["type"]=="klammer") {								$W["value"] = $this->parse2($W["value"]);							}							$K2[] = $W;							//$K2[] = $Z[$i]; 							$K[count($K)-1] = array("type"=>"klammer", "division"=>true, "value" => $K2 );						} else if($Z[$i]["type"]=="^") {														$K2 = array($K[count($K)-1]);							$K2[] = $Z[$i];							$i++;							$W = $Z[$i];							if($W["type"]=="klammer") {								$W["value"] = $this->parse2($W["value"]);							}							$K2[] = $W;							$K[count($K)-1] = array("type"=>"klammer", "potenz"=>true, "value" => $K2 );						} else {							$W = $Z[$i];							if($W["type"]=="klammer") {								$W["value"] = $this->parse2($W["value"]);							}							$K[] = $W;						}					} else {						//$i-=2;						break;					}					$i++;				}				//if($K2[0]["type"]=="klammer") $K2 = $this->parse2($K2);				$Z2[] = array("type"=>"klammer", "auto"=>true, "value" => $K );				if($i+1<count($Z)) $Z2[] = $Z[$i];			}			// }}}		}					return($Z2);		// }}}	}				function drawFormel($Z, $depth=0, $Zx=array(), $fontsize=-1 ) {		// {{{				if($fontsize==-1) $fontsize = $this->ttfSize;		// Im ersten Durchlauf nur die Klammern abarbeiten		for($i=0;$i<count($Z);$i++) {			// {{{			if($Z[$i]["type"]=="klammer") {				$fs = $fontsize;				if($Zx["potenz"] && $i==2) $fs *= 0.8;				$Z[$i]["img"] = $this->drawFormel($Z[$i]["value"], $depth+1, $Z[$i], $fs);				$Z[$i]["imgWidth"] = imageSx($Z[$i]["img"]);				$Z[$i]["imgHeight"] = imageSy($Z[$i]["img"]);			} 			// }}}		}				// Nun die anderen Zeichen abarbeiten		for($i=0;$i<count($Z);$i++) {			// {{{			if($Z[$i]["type"]!="klammer") {				if($this->useTTF) {					$text_data = imagettfbbox( $fontsize, 0, $this->ttfFile, $Z[$i]["value"] );					$posX_font = min($text_data[0], $text_data[6]) * -1;					$posY_font = min($text_data[5], $text_data[7]) * -1;					$height = max($text_data[1], $text_data[3]) - min($text_data[5], $text_data[7])+2;					$width = max($text_data[2], $text_data[4]) - min($text_data[0], $text_data[6])+2;													$Z[$i]["img"] = imageCreate( $width, $height );					$white = imageColorAllocate($Z[$i]["img"], 255,255,255);					$col = imageColorAllocate($Z[$i]["img"], 0,0,0);					$fs = $fontsize;					if($Zx["potenz"] && $i==2) $fs *= 0.8;					imagettftext( $Z[$i]["img"], $fs, 0, $posX_font, $posY_font, $col, $this->ttfFile, $Z[$i]["value"] );				} else {					$width = strlen($Z[$i]["value"])*10;					$height = 15;					$Z[$i]["img"] = imageCreate( $width, $height );					$white = imageColorAllocate($Z[$i]["img"], 255,255,255);					$col = imageColorAllocate($Z[$i]["img"], 0,0,0);					imagestring($Z[$i]["img"], 2,2,2,$Z[$i]["value"], $col);				}								$Z[$i]["imgWidth"] = imageSx($Z[$i]["img"]);				$Z[$i]["imgHeight"] = imageSy($Z[$i]["img"]);							} 			// }}}		}				if($Zx["potenz"]) {			$maxHeight = $Z[0]["imgHeight"] + ($Z[2]["imgHeight"]*0.8)+10;			$maxWidth = $Z[0]["imgWidth"] + $Z[2]["imgWidth"]+10;			$im = imageCreate($maxWidth, $maxHeight);			$white = imageColorAllocate($im, 255,255,255);			$col = imageColorAllocate($im, 0,0,0);						$x = 0;			$y = 0;			imageCopy($im, $Z[0]["img"], 2, $maxHeight-$Z[0]["imgHeight"]-2 , 0,0, $Z[0]["imgWidth"], $Z[0]["imgHeight"]);			$x += $Z[0]["imgWidth"]+5;			$y += $Z[0]["imgHeight"]+5;			imageCopy($im, $Z[2]["img"], $maxWidth-$Z[2]["imgWidth"]-2,2, 0,0, $Z[2]["imgWidth"], $Z[2]["imgHeight"]);								} else if($Zx["division"]) {			// {{{			$maxWidth=0;			for($i=0;$i<count($Z);$i++) {				if($Z[$i]["imgWidth"] > $maxWidth) $maxWidth = $Z[$i]["imgWidth"];			}			$maxWidth += 10;			$im = imageCreate($maxWidth, $Z[0]["imgHeight"] + $Z[2]["imgHeight"]+10);			$white = imageColorAllocate($im, 255,255,255);			$col = imageColorAllocate($im, 0,0,0);						$y = 0;			imageCopy($im, $Z[0]["img"], $maxWidth/2-$Z[0]["imgWidth"]/2,0 , 0,0, $Z[0]["imgWidth"], $Z[0]["imgHeight"]);			$y += $Z[0]["imgHeight"]+5;			imageCopy($im, $Z[2]["img"], $maxWidth/2-$Z[2]["imgWidth"]/2,$y , 0,0, $Z[2]["imgWidth"], $Z[2]["imgHeight"]);						imageLine($im, 2,$y-2, $maxWidth-2, $y-2, $col );			// }}}		} else {			// {{{			$maxHeight=0;			$sumWidth = 0;			for($i=0;$i<count($Z);$i++) {				$sumWidth += $Z[$i]["imgWidth"];				if($Z[$i]["imgHeight"] > $maxHeight) $maxHeight = $Z[$i]["imgHeight"];			}			$maxHeight+=6;									$x=5;			$addWidth=10;						if($Zx["function"]=="WURZEL") {				$addWidth += 10;			} else if($Zx["function"]!="") {								if($this->useTTF) {					$text_data = imagettfbbox( $this->ttfSize, 0, $this->ttfFile, $Zx["function"] );					$posX_font = min($text_data[0], $text_data[6]) * -1;					$posY_font = min($text_data[5], $text_data[7]) * -1;					$height = max($text_data[1], $text_data[3]) - min($text_data[5], $text_data[7]);					$width = max($text_data[2], $text_data[4]) - min($text_data[0], $text_data[6]) + 4;													$funcImg = imageCreate( $width, $height );					$white = imageColorAllocate($funcImg, 255,255,255);					$col = imageColorAllocate($funcImg, 0,0,0);					imagettftext( $funcImg, $this->ttfSize, 0, $posX_font, $posY_font, $col, $this->ttfFile, $Zx["function"] );													} else {					$width = strlen($Zx["function"])*10;					$height = 15;					$funcImg = imageCreate( $width, $height );					$white = imageColorAllocate($funcImg, 255,255,255);					$col = imageColorAllocate($funcImg, 0,0,0);					imagestring($funcImg, 2,2,2,$Zx["function"], $col);				}								$x=2;				$addWidth += $width;			}				$im = imageCreate($sumWidth+$addWidth, $maxHeight);			$white = imageColorAllocate($im, 255,255,255);			$col = imageColorAllocate($im, 0,0,0);						if($Zx["function"]=="WURZEL") {				$x += 10;			} else if($Zx["function"]!="") {				imageCopy($im, $funcImg, $x, $maxHeight/2-$height/2, 0,0, $width, $height);				$x += $width;			}			if( ($depth>0 || $Zx["function"]!="") && $Zx["function"]!="WURZEL" && ($Z[0]["type"]!="klammer" || count($Z[0]["value"])>1) ) imageArc($im, $x+4-5,$maxHeight/2, 8, $maxHeight-2, 90,270, $col);			for($i=0;$i<count($Z);$i++) {				// {{{				imageCopy($im, $Z[$i]["img"], $x, $maxHeight/2-$Z[$i]["imgHeight"]/2, 0,0, $Z[$i]["imgWidth"], $Z[$i]["imgHeight"]);				$x += $Z[$i]["imgWidth"];				// }}}			}			if( ($depth>0 || $Zx["function"]!="") && $Zx["function"]!="WURZEL" && ($Z[0]["type"]!="klammer" || count($Z[0]["value"])>1) ) imageArc($im, $x+1,$maxHeight/2, 8, $maxHeight-2, 270,90, $col);						if($Zx["function"]=="WURZEL") {				imageLine($im, 1, $maxHeight/3,5, $maxHeight/3, $col );				imageLine($im, 5, $maxHeight/3,8, $maxHeight-2, $col );				imageLine($im, 8, $maxHeight-2, 11, 1, $col );				imageLine($im, 11,0 , $sumWidth+$addWidth, 0, $col );				imageLine($im, $sumWidth+$addWidth-1, 0,$sumWidth+$addWidth-1, 4, $col );			}						// }}}		}				return($im);				// }}}	}		function getImage($f) {		// {{{		$Z = $this->parse($f);		$Z2 = $this->parse2($Z);		$im = $this->drawFormel($Z2);		return($im);		// }}}	}}?><html><body><?phpif($_POST["formelstring"]!="") {	$FP = new formel();		/*	// Aktivate this to use TTF-Font.	// copy a fontfile like arial.ttf in this directory.	$FP->useTTF(dirname(__FILE__)."/arial.ttf");	$FP->ttfSize=15;	*/		$im  = $FP->getImage($_POST["formelstring"]); 	imagePng($im, "formel.png");		echo "<script>parent.document.getElementById('image').src='formel.png?x=".time()."';</script>";		exit;}?><?phpif($_POST["formelstring"]=="") $_POST["formelstring"] = "x=WURZEL(1+2/3)/(1+2)";?><h2>render formula</h2><form method="post" target="formelimage" name="formel">formula: <input type="text" size=80 name="formelstring" value="<?php echo $_POST["formelstring"];?>" onKeyUp="sendFormel();"></form> <p><img src="formel.png?x=<?php echo time();?>" id="image"></p><hr size=1>Use: + - * / () and WURZEL() for square root.<br>e.g.: 1+2-3/5 or c=WURZEL(a^2+b^2)<hr size=1><script>var sendCount=0;function doSend() {	// {{{	if(sendCount>0) {		sendCount--;		if(sendCount==0) {			document.formel.submit();			sendCount=0;		}	}	setTimeout("doSend()", 100);	// }}}}setTimeout("doSend()", 100);function sendFormel() {	// {{{	sendCount=5;	// }}}}</script><iframe src="about:blank" width=1 height=1 border=0 frameborder=0 name="formelimage"></iframe></body></html>