/// <summary>
/// Updates the asteroids.
/// </summary>
/// <param name="delta">The delta.</param>
/// <param name="inputState">State of the input.</param>
private void UpdateAsteroids(long delta, Input inputState)
{
for (int i = _asteroids.Count - 1; i >= 0; i--)
{
_asteroids[i].Update(GraphicsDevice, inputState, delta);
if (_asteroids[i].Active == false)
{
Asteroid parent = _asteroids[i];
if (parent.Generation <= 2)
{
var asteroid = new Asteroid();
asteroid.Initialize(GraphicsDevice.Viewport, _asteroidTexture, parent.Position,
parent.Radians - _rand.Next(10, 30) * Math.PI / 180, parent.Speed * 1.1f,
parent.Generation + 1);
_asteroids.Add(asteroid);
asteroid = new Asteroid();
asteroid.Initialize(GraphicsDevice.Viewport, _asteroidTexture, parent.Position,
parent.Radians + _rand.Next(10, 30) * Math.PI / 180, parent.Speed * 1.1f,
parent.Generation + 1);
_asteroids.Add(asteroid);
}
var explosion = new Explosion
{
Active = true,
Position =
parent.Position - new Vector2((float)(parent.Width / 2.0), (float)(parent.Height / 2.0)),
Scale = (float)parent.Scale,
Texture = parent.Texture,
Velocity = new Vector2()
};
_explosionSound.Play();
_explosions.Add(explosion);
_asteroids.RemoveAt(i);
if (_asteroids.Count == 0)
{
_wave += 1;
StartWave(_wave);
}
}
}
}
/// <summary>
/// Starts the wave of asteroids.
/// The higher the wave number the harder the wave will be
/// </summary>
/// <param name="wave">The wave.</param>
private void StartWave(int wave)
{
int asteroids = (wave + 4 < 12) ? wave + 4 : 12;
for (int i = 0; i < asteroids; ++i)
{
double direction = _rand.NextDouble() * Math.PI * 2;
double x = GraphicsDevice.Viewport.Width / 2.0 + GraphicsDevice.Viewport.Width * Math.Cos(direction);
double y = GraphicsDevice.Viewport.Height / 2.0 + GraphicsDevice.Viewport.Height * Math.Sin(direction);
x = MathHelper.Clamp((float)x, 0, GraphicsDevice.Viewport.Width);
y = MathHelper.Clamp((float)y, 0, GraphicsDevice.Viewport.Height);
double init = _rand.NextDouble() * Math.PI * 2;
var asteroid = new Asteroid();
float speed = 50.0f;
if (wave > 12)
{
speed += wave - 12 * 10;
}
asteroid.Initialize(GraphicsDevice.Viewport, _asteroidTexture, new Vector2((int)x, (int)y), init,
(float)Math.Floor(speed + ((_rand.NextDouble() - .5)) * 25), 1);
_asteroids.Add(asteroid);
}
}