Question

I have developed a class for Minecraft in PHP, one of the most recent additions to the functions is a skin preview but I am having a little trouble working out the codes for the full body preview (head preview works fine), the code I am using for the head preview is as follows…

header('Content-Type: image/png');
$canvas = imagecreatetruecolor($size, $size);
$image = imagecreatefrompng($this->custom_skin($username));
imagecopyresampled($canvas, $image, 0, 0, 8, 8, $size, $size, 8, 8);
return imagepng($canvas);

https://github.com/nblackburn/minecraft/blob/master/class.minecraft.php

Any contributions would be a huge help to get this full body preview working.

Answer 1

Have a look at this skin template http://www.minecraftwiki.net/images/5/54/Skintemplate.png

Based on that the regions should be:

head        x8 y8 w8 h8 
body front  x20 y20 w8 h12
arm front   x44 y20 w4 h12
leg front   x4 y20 w4 h12

You may need to flip the arm and leg sections in order to get the left and right to be mirrored.

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

$scale = $size / 16;
$canvas = imagecreatetruecolor(16*$scale, 32*$scale);
$image = imagecreatefrompng($this->custom_skin($username));

imagealphablending($canvas, false);
imagesavealpha($canvas,true);
$transparent = imagecolorallocatealpha($canvas, 255, 255, 255, 127);
imagefilledrectangle($canvas, 0, 0, 16*$scale, 32*$scale, $transparent);

imagecopyresized($canvas, $image, 4*$scale,  0*$scale,  8,   8,   8*$scale,  8*$scale,  8,  8);  //head
imagecopyresized($canvas, $image, 4*$scale,  8*$scale,  20,  20,  8*$scale,  12*$scale, 8,  12); //body
imagecopyresized($canvas, $image, 0*$scale,  8*$scale,  44,  20,  4*$scale,  12*$scale, 4,  12); //arm left
imagecopyresampled($canvas, $image, 12*$scale, 8*$scale,  47,  20,  4*$scale,  12*$scale, -4,  12); //arm right (flipped)
imagecopyresized($canvas, $image, 4*$scale,  20*$scale, 4,   20,  4*$scale,  12*$scale, 4,  12); //leg left
imagecopyresampled($canvas, $image, 8*$scale,  20*$scale, 7,   20,  4*$scale,  12*$scale, -4,  12); //leg right (flipped)

return imagepng($canvas);

The above is just from memory but it should point you in the right direction. You shouldn’t use imagecopyresampled when upscaling since in this case you want to avoid interpolation.