render.php

<?php
function flip(&$img)
{
	$size_x = imagesx($img);
	$size_y = imagesy($img);
	$temp = imagecreatetruecolor($size_x, $size_y);
	$x = imagecopyresampled($temp, $img, 0, 0, ($size_x-1), 0, $size_x, $size_y, 0-$size_x, $size_y);
	return $temp;
}

// File and new size
$filename = 'http://www.minecraft.net/skin/' . $_GET['user'] . '.png';

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

// Load
$rendered = imagecreatetruecolor(240, 480);
$source = imagecreatefrompng($filename);
$b = 120;
$s = 8;

// Fill the new image with pink and set pink as the transparent colour
$pink = imagecolorallocate($rendered, 255, 0, 255);
imagefilledrectangle($rendered, 0, 0, 240, 480, $pink);
imagecolortransparent($rendered, $pink);

// Create a flipped version of the image
$fsource = flip($source);

// Annatomy of an imagecopyresampled function
// $dst_image , $src_image , $dst_x , $dst_y , $src_x , $src_y , $dst_w , $dst_h , $src_w , $src_h

// Check if we want to render the back or front
if (isset($_GET['back']))
{
	// Render the back
	
	// Copy head
	imagecopyresampled($rendered, $source, $b / 2, 0, $s * 3, $s, $b, $b, $s, $s);
	
	// Copy the head accesory
	imagecopyresampled($rendered, $source, $b / 2, 0, $s * 7, $s, $b, $b, $s, $s);
	
	// Copy the body
	imagecopyresampled($rendered, $source, $b / 2, $b, $s * 4, $s * 2.5, $b, $b * 1.5, $s, $s * 1.5);
	
	// Copy the left arm
	imagecopyresampled($rendered, $source, $b * 1.5, $b, $s * 6.5, $s * 2.5, $b / 2, $b * 1.5, $s / 2, $s * 1.5);
	
	// Copy the right arm
	imagecopyresampled($rendered, $fsource, 0, $b, $s * 1, $s * 2.5, $b / 2, $b * 1.5, $s / 2, $s * 1.5);
	
	// Copy the left leg
	imagecopyresampled($rendered, $source, $b * 1, $b * 2.5, $s * 1.5, $s * 2.5, $b / 2, $b * 1.5, $s / 2, $s * 1.5);
	
	// Copy the right leg
	imagecopyresampled($rendered, $fsource, 60, $b * 2.5, $s * 6, $s * 2.5, $b / 2, $b * 1.5, $s / 2, $s * 1.5);
}
else
{
	// Render the front
	
	// Copy head
	imagecopyresampled($rendered, $source, $b / 2, 0, $s, $s, $b, $b, $s, $s);
	
	// Copy the head accesory
	imagecopyresampled($rendered, $source, $b / 2, 0, $s * 5, $s, $b, $b, $s, $s);
	
	// Copy the body
	imagecopyresampled($rendered, $source, $b / 2, $b, $s * 2.5, $s * 2.5, $b, $b * 1.5, $s, $s * 1.5);
	
	// Copy the left arm
	imagecopyresampled($rendered, $source, $b * 1.5, $b, $s * 5.5, $s * 2.5, $b / 2, $b * 1.5, $s / 2, $s * 1.5);
	
	// Copy the right arm
	imagecopyresampled($rendered, $fsource, 0, $b, $s * 2, $s * 2.5, $b / 2, $b * 1.5, $s / 2, $s * 1.5);
	
	// Copy the left leg
	imagecopyresampled($rendered, $source, 60, $b * 2.5, $s / 2, $s * 2.5, $b / 2, $b * 1.5, $s / 2, $s * 1.5);
	
	// Copy the right leg
	imagecopyresampled($rendered, $fsource, $b * 1, $b * 2.5, $s * 7, $s * 2.5, $b / 2, $b * 1.5, $s / 2, $s * 1.5);
}

// Output to the browser
imagepng($rendered);