$type1 = $type2 = $type3 = NULL;

while($entity = array_shift($collection)) {
    if ($type1 && $type2 && $type3) {
        break;
    }

    if (!$type1 && $entity->type = 1) {
        $type1 = $entity;
    }
    else if (!$type2 && $entity->type = 2) {
        $type2 = $entity;
    } else if (!$type3 && $entity->type = 3) {
        $type3 = $entity;
    }

}