private static void CollidePlayerEnemy(PlayerVerticalShooter player, EnemyShip enemy)
 {
     player.InflictDamage(enemy);
     enemy.InflictDamage(player);
 }
 private static void CollideEnemyAlly(EnemyShip enemy, AlliedShip ally)
 {
     enemy.InflictDamage(ally);
     ally.InflictDamage(enemy);
 }
 private static void CollideBulletEnemy(PlayerBullet bullet, EnemyShip enemy)
 {
     bullet.InflictDamage(enemy);
     enemy.LastHitBy = bullet.Tracker;
     enemy.InflictDamage(bullet);
 }