public static function imageUrl($width = 640, $height = 480, $category = null, $randomize = true, $word = null, $gray = false)
{
$baseUrl = "http://lorempixel.com/";
$url = "{$width}/{$height}/";
if ($gray) {
$url = "gray/" . $url;
}
if ($category) {
if (!in_array($category, static::$categories)) {
throw new \InvalidArgumentException(sprintf('Unknown image category "%s"', $category));
}
$url .= "{$category}/";
if ($word) {
$url .= "{$word}/";
}
}
if ($randomize) {
$url .= '?' . static::randomNumber(5, true);
}
return $baseUrl . $url;
}