public function cloneCore($core)
    {
        $width = imagesx($core);
        $height = imagesy($core);
        $clone = imagecreatetruecolor($width, $height);
        imagealphablending($clone, false);
        imagesavealpha($clone, true);
        $transparency = imagecolorallocatealpha($clone, 0, 0, 0, 127);
        imagefill($clone, 0, 0, $transparency);
        
        imagecopy($clone, $core, 0, 0, 0, 0, $width, $height);

        return $clone;
    }