imagecreate (percenatage?)

[JDcrack]

I was wondering if there was a creative way to set the width in imagecreate to a percantage instead of px X px
EXAMPLE:
imagecreate(100%, 50%);
Really I would like to create an image that is 100% of the screen width.
Here is my current code:

  $im = imagecreate(640,50);
  $white = imagecolorallocate($im, 255,255,255);
  $black = imagecolorallocate($im, 0,0,0);
  imagecolortransparent($im,$white);
  $text=stripslashes($_GET["text"]);
  imagettftext($im, 26, 0, 26, 36, $black, $font, "$text");
  imagepng($im);
  imagedestroy($im);

Any thoughts or ideas?

[JDcrack]

<script>
var screenHeight = screen.height;
var screenWidth = screen.width;
</script>

I really didnt want to use any javascript,
but perhaps there is a way to do this:
imagecreate($screenWidth,50);

[JDcrack]

Ok I found a solution,
but it feels a bit sloppy to me...
any suggestions on how to make this better:

//file calling image_script.php:
<script language="JavaScript">
<!--
var screenHeight = screen.height;
var screenWidth = screen.width;

document.write('<img src="image_script.php?width='+ screenWidth +'&text=TEST&font=font.ttf">'); 
--> 
</script> 


//image_script.php:
<?php
  header("Content-type: image/png");
  $width = $_GET["width"];
  $im = imagecreate($width,50);
  $white = imagecolorallocate($im, 255,255,255);
  $black = imagecolorallocate($im, 0,0,0);
  imagecolortransparent($im,$white);
  $text=stripslashes($_GET["text"]);
  // Replace path by your own font path
  imagettftext($im, 26, 0, 26, 36, $black, $font,"$text");
  imagepng($im);
  imagedestroy($im);
?>

[Mordecai]

Originally posted by JDcrack
document.write('<img src="image_script.php?width='+ screenWidth +'&text=TEST&font=font.ttf">');

This is all good until someone comes along and realises how the URL works... They decide that they're going to mess with your server: image_script.php?width=1000000000000000000000000000000000000000000000000000000&text=hahaha,%20your%20server%20%20crashed&font=font.ttf
Bravo, your server crashed. What can you do about this? Well, you could record the width of all resolutions known, and that would perhaps suffice. That is, unless someone comes along with a screen dimension they created, and your script fails. This is still probably the best path to follow, however.

I'd try to stay away from JavaScript (and apparently you agree with me), but that does seem to be the way to do it best.

[JDcrack]

Thanks for the note, but I already have that covered:
at the very top of image_script.php I have:

if (strstr($PHP_SELF, "image_script.php") || $_GET["width"] > 4000) {
	exit();
}

you think thats good enough?

Also, you have any ideas on how to do this without JS?

Thanks!

[Mordecai]

You'll clearly need some kind of client-side communication. There's no way to do it with PHP alone.