<?php

$im = imagecreatefrompng("images/ndmap.png");
$fg = imagecolorallocate($im, 0, 0, 0);

if ($_GET["counties"] != "")
    {
    $codes = explode(",", $_GET["counties"]);
    foreach ($codes as &$value)
	{
	$coord = explode("-", $value);
	imagefilledellipse($im, $coord[0], $coord[1], 35, 35, $fg);
	}
    }


header('Content-Type: image/png');

imagepng($im);
imagedestroy($im);

?>