/// <summary>
/// Takes a snapshot of the Emitters state.
/// </summary>
/// <param name="snap"></param>
protected override void TakeSnapshot(ref Snapshot snap)
{
base.TakeSnapshot(ref snap);
CircleSnapshot circleSnap = (CircleSnapshot)snap;
circleSnap.Radius = _radius;
circleSnap.Ring = _ring;
}
/// <summary>
/// Processes a Particle to give it its initial position and orientation.
/// </summary>
/// <param name="snap">Snapshot taken when the Particle was discharged.</param>
/// <param name="position">The Particles offset from the position of the Emitter.</param>
/// <param name="orientation">The particles orientation (unit vector).</param>
protected override void GetParticlePositionAndOrientation(Snapshot snap, ref Vector2 position, ref Vector2 orientation)
{
CircleSnapshot circleSnap = (CircleSnapshot)snap;
float angle = (float)Rnd.NextDouble() * MathHelper.TwoPi;
orientation.X = (float)Math.Sin(angle);
orientation.Y = (float)Math.Cos(angle);
float distance = circleSnap.Radius;
if (!circleSnap.Ring)
{
distance *= (float)Rnd.NextDouble();
}
position.X = (float)Math.Sin(angle) * distance;
position.Y = (float)Math.Cos(angle) * distance;
}