GD help with tricky situation

[IDTstudios1]

the following fuction draws lines onto an image. The data comes from an e00 geographic vector file. Is there anyways that I could modify the following code to "fill in" everything in the middle of the lines?

class e00 extends map {
/**
* draws a datafile into the image
*
* @param $img image-handler
* @param $fn filename of the datafile
* @param $col color used for drawing
*/

function draw($fn, $col) {
if (($f = fopen($fn, "r")) == false) return false;

$num_records = 0;
$ln = 0;

while(0 || $line = fgets($f, 1024)) {
$ln ++;

# a node definition
if ($num_records == 0 &&
preg_match("#^\s+([0-9]+)\s+([-0-9]+)\s+([0-9]+)\s+([0-9]+)\s+([0-9]+)\s+([0-9]+)\s+([0-9]+)#", $line, $a)) {
$num_records = $a[7];

$pl['x'] = -1;
$pl['y'] = -1;

# 2 coordinates
} else if ($num_records &&
preg_match("#^ *([-+]?[0-9]\.[0-9]{7}E[-+][0-9]{2}) *([-+]?[0-9]\.[0-9]{7}E[-+][0-9]{2}) *([-+]?[0-9]\.[0-9]{7}E[-+][0-9]{2}) *([-+]?[0-9]\.[0-9]{7}E[-+][0-9]{2})#", $line, $a)) {

# print $a[0]."<br />";

if ($pl['x'] != -1 &&
$pl['y'] != -1
) {

$this->draw_clipped($pl['x'], $pl['y'],
$a[1], $a[2],
$col);
}

$num_records--;

$this->draw_clipped($a[1], $a[2],
$a[3], $a[4],
$col);

$pl["x"] = $a[3];
$pl["y"] = $a[4];

$num_records--;

# 1 coordinate
} else if ($num_records &&
preg_match("#^ *([-+]?[0-9]\.[0-9]{7}E[-+][0-9]{2}) *([-+]?[0-9]\.[0-9]{7}E[-+][0-9]{2})#", $line, $a)) {

if ($pl['x'] != -1 &&
$pl['y'] != -1
) {

$this->draw_clipped($pl['x'], $pl['y'],
$a[1], $a[2],
$col);

$pl["x"] = $a[1];
$pl["y"] = $a[2];
}

$num_records--;


# done
} else if ($ln > 2) {
# print "died at: ".$ln."<br />";
break;
} else {
# print $line."<br />";
}
}

fclose($f);
}
}

this is from the Pear::Image_GIS package if it helps.

Any help / tips / pointing in the rigth direction would be appreciated,

Thanks