/*public static Engine.Calc.Vector ExpressiveForce(this Engine.Effects.Particles.Attractor attractor,
* Engine.Effects.Particles.ForceParticle p)
* {
* float G = 4f;
*
* Engine.Calc.Vector relDistance = attractor.Distance(p);
*
* float distance = relDistance.Norm; // Norm seems the magnitude in Processing
*
* float force = G / distance;
*
* force = Engine.Calc.Math.Sigmoid(force);
*
* relDistance.Normalize();
* Engine.Calc.Vector.Multiply(relDistance, force);
*
* return relDistance;
* }*/
/// <summary>
///
/// </summary>
/// <param name="attractor"></param>
/// <param name="p"></param>
/// <param name="G">The "Gravitational constant" of the force (suggested value 1.3)</param>
/// <param name="expansion">Allows the force to be stronger or weaker on longer distances while remaining weak at very short distances.
/// suggested value 2.8</param>
/// <param name="direction">the direction of the force. positive makes the force attraction, negative makes the force repulsion. suggested value 0.5 or -0.5</param>
/// <returns></returns>
public static Engine.Calc.Vector ModularForce(this Engine.Effects.Particles.Attractor attractor,
Engine.Effects.Particles.ForceParticle p)
{
Engine.Calc.Vector relDistance = attractor.Distance(p);
double distance = System.Math.Sqrt(relDistance.X * relDistance.X + relDistance.Y * relDistance.Y);
double force = (attractor.Intensity * attractor.Force * distance) - 10d / System.Math.Pow(attractor.Expression, -1 * (distance / attractor.Force));
relDistance.Normalize();
relDistance *= force;
return(relDistance);
}
public static Engine.Calc.Vector Distance(this Engine.Effects.Particles.Attractor attractor, Engine.Effects.Particles.BaseParticle p)
{
Engine.Calc.Vector distance = attractor.Position - p.Position;
return(distance);
}
/// <summary>
/// Updates the position of the particule according to its own position, velocity, and the force (and location) of the
/// specified attractor.
/// </summary>
/// <param name="attractor"></param>
public void Update(Engine.Effects.Particles.Attractor attractor)
{
//t_acceleration = attractor.ExpressiveForce(this);
t_acceleration = attractor.ModularForce(this);
Update();
}
