private void DestroyBullets()
{
List <WorldObject> doomedBullets = new List <WorldObject>();
foreach (WorldObject bullet in bullets.Children)
{
if (bullet.OutOfMap())
{
doomedBullets.Add(bullet);
score.AddBullets(1);
}
}
foreach (WorldObject bullet in doomedBullets)
{
bullets.Remove(bullet);
}
}