Bar Chart Generator

<?php
function new_barchart($values, $labels, $x_axis_label, $y_axis_label, $title, $bar_width = 100) {
	$bars = $values;
	sort($values, SORT_NUMERIC);
	$highest_value = $values[count($values)-1];
	/*if(strlen($highest_value)>2) {
		$division_by = pow(10, strlen($highest_value) - 2);
		for($i=0;$i<count($bars);$i++) {
			$bars[$i] = $bars[$i] / $division_by;
		}
	}
	else
		$division_by = 1;*/
	$division_by = 1;
	while($highest_value>250) {
		$highest_value /= 3;
		$division_by *= 3;
	}
	if($division_by!=1) {
		$highest_value *= $division_by;
		for($i=0;$i<count($bars);$i++) {
			$bars[$i] = $bars[$i] / $division_by;
		}
	}
	//	$division_by = 1;
	$barchart = imagecreatetruecolor(1, 1);
	$title_coordinates = imagettftext($barchart, 10, 0, 0, 10, 0, 'C:/Windows/Fonts/arialbd.ttf', $title); // draw the title to get its coordinates
	$y_axis_max_value = imagettftext($barchart, 10, 0, 0, $title_coordinates[1], 0, 'C:/Windows/Fonts/arialbd.ttf', $highest_value); // draw the y-axis max value label
	$width_of_chart = count($bars) * ($bar_width + 10) + $y_axis_max_value[2] + 10;
	$barchart = imagecreatetruecolor($title_coordinates[2] > $width_of_chart ? $title_coordinates[2] : $width_of_chart, $title_coordinates[3] + 11 + $highest_value / $division_by);
	imagefilledrectangle($barchart, 0, 0, imagesx($barchart), imagesy($barchart), imagecolorallocate($barchart, 255, 255, 255)); // color the background white
	imagettftext($barchart, 10, 0, 0, 10, 0, 'C:/Windows/Fonts/arialbd.ttf', $title); // draw the title again
	$max_value_label_coordinates = imagettftext($barchart, 10, 0, 0, 31, 0, 'C:/Windows/Fonts/arialbd.ttf', $highest_value); // draw the max value label
	$middle_of_max_value_label = ($max_value_label_coordinates[7] + $max_value_label_coordinates[1]) / 2;
	imagefilledrectangle($barchart, $max_value_label_coordinates[2] + 10, $middle_of_max_value_label, $max_value_label_coordinates[2] + 3, $middle_of_max_value_label + 1, 0); // draw the line from the y-axis to the max value label
	imagefilledrectangle($barchart, $max_value_label_coordinates[2] + 10, $title_coordinates[3] + 12, $max_value_label_coordinates[2] + 11, imagesy($barchart), 0); // draw the y-axis
	imagefilledrectangle($barchart, $max_value_label_coordinates[2] + 10, imagesy($barchart) - 2, imagesx($barchart), imagesy($barchart), 0); // draw the x-axis
	/* START: Draw bars */
	$previous_bar_right = $max_value_label_coordinates[2] + 12;
	$i = 0;
	foreach($bars as $bar) {
		imagefilledrectangle($barchart, $previous_bar_right, imagesy($barchart) + 1 - $bar, $previous_bar_right + $bar_width, imagesy($barchart) - 3, imagecolorallocate($barchart, rand(25, 255), rand(25, 255), rand(25, 255)));
		imagettftext($barchart, 10, 0, $previous_bar_right + 2, imagesy($barchart) - 5, 0, 'C:/Windows/Fonts/arialbd.ttf', $labels[$i]);
		$previous_bar_right += $bar_width + 10;
		$i++;
	}
	/* END: Draw bars */
	header('Content-Type: image/png');
	imagepng($barchart);
}
 
new_barchart(array(30.45e6, 34e6, 3312e3), array('Space Shuttle', 'Saturn V', 'Delta IV'), 0, 0, 'Comparison of launch vehicle thrust (Meganewtons)');
?>