/// <summary>
/// Create an asteroid
/// </summary>
/// <param name="content"></param>
/// <param name="graphicsDevice"></param>
/// <returns></returns>
private Asteroid CreateAsteroid(ContentManager content, GraphicsDevice graphicsDevice)
{
/// Create an asteroid
var asteroid = new Asteroid(this, player);
asteroid.Initialize(content, graphicsDevice);
/// Initilizes asteroid default values
float speed = 1.0f;
float x = 0.0f;
float y = 0.0f;
Vector2 direction = Vector2.Zero;
var corner = random.Next(0, 3);
/// Determine what direction the asteroid comes from.
switch (corner)
{
case 0:
x = graphicsDevice.Viewport.X + asteroid.Width / 2;
y = graphicsDevice.Viewport.Y + asteroid.Height / 2;
asteroid.CurrentSpeed = new Vector2(1.0f * speed, 1.0f * speed);
break;
case 1:
x = graphicsDevice.Viewport.Width - asteroid.Width / 2;
y = graphicsDevice.Viewport.Y + asteroid.Height / 2;
asteroid.CurrentSpeed = new Vector2(-1.0f * speed, 1.0f * speed);
break;
case 2:
x = graphicsDevice.Viewport.X + asteroid.Width / 2;
y = graphicsDevice.Viewport.Height - asteroid.Height / 2;
asteroid.CurrentSpeed = new Vector2(1.0f * speed, -1.0f * speed);
break;
case 3:
x = graphicsDevice.Viewport.Width - asteroid.Width / 2;
y = graphicsDevice.Viewport.Height - asteroid.Height / 2;
asteroid.CurrentSpeed = new Vector2(-1.0f * speed, -1.0f * speed);
break;
default:
break;
}
asteroid.Position = new Vector2(x, y);
asteroids.Add(asteroid);
return asteroid;
}
/// <summary>
/// Remove dead asteroids from the map
/// </summary>
/// <param name="content">The content manager</param>
/// <param name="graphicsDevice">The graphics device</param>
/// <param name="player">The player</param>
private void RemoveDeadAsteroids(ContentManager content, GraphicsDevice graphicsDevice, Player player)
{
/// Remove dead asteroids
for (int i = asteroids.Count - 1; i >= 0; i--)
{
var asteroid = asteroids[i];
if (!(asteroid.Killer is EnemyBullet) && asteroid.Dead)
{
/// Add to the player's score
player.Score += asteroid.ScoreWorth;
}
if (asteroid.Dead)
{
var nextSize = (asteroid.Size == Sizes.Large) ? Sizes.Medium : Sizes.Small;
var explosion = CreateExplosion(nextSize, asteroid.Position, content, graphicsDevice);
entityManager.Add(explosion);
explosion.PlayExplosionSound();
/// Split the asteroid into smaller asteroids.
var splitAsteroids = new List<Asteroid>();
if (asteroid.Size != Sizes.Small)
{
var a1 = new Asteroid(this, player, nextSize);
var a2 = new Asteroid(this, player, nextSize);
a1.Position = new Vector2(asteroid.Position.X, asteroid.Position.Y + 15);
a1.CurrentSpeed = asteroid.CurrentSpeed;
a2.Position = asteroid.Position;
a2.CurrentSpeed = new Vector2(-asteroid.CurrentSpeed.X, -asteroid.CurrentSpeed.Y);
splitAsteroids.AddRange(new Asteroid[] { a1, a2 });
}
/// Remove the asteroid
Remove(asteroid);
foreach (var newAsteroid in splitAsteroids)
{
entityManager.Add(newAsteroid);
asteroids.Add(newAsteroid);
}
}
}
}
/// <summary>
/// Remove an asteroid from the asteroid manager
/// </summary>
/// <param name="asteroid"></param>
public void Remove(Asteroid asteroid)
{
asteroids.Remove(asteroid);
freshAsteroids.Remove(asteroid);
entityManager.Remove(asteroid);
}