private void PlayerTwoMove(FrameEventArgs e) { KeyboardState kb = Keyboard.GetState(); Artillery artilleryTwo = (Artillery)gameObjects[1]; Vector2 oldPosition = artilleryTwo.Transform.Position; if (kb.IsKeyDown(Key.Left) ^ kb.IsKeyDown(Key.Right)) { if (kb.IsKeyDown(Key.Left)) { artilleryTwo.Move(Direction.Left, e.Time); } else { artilleryTwo.Move(Direction.Right, e.Time); } if (CheckCollision(artilleryTwo)) { artilleryTwo.Transform.Position = oldPosition; } } }