/// <summary>
/// When overridden in the derived class, handles processing the <paramref name="particle"/> when
/// it is updated. Only valid if <see cref="ParticleModifier.ProcessOnUpdate"/> is set.
/// </summary>
/// <param name="emitter">The <see cref="ParticleEmitter"/> that the <paramref name="particle"/>
/// came from.</param>
/// <param name="particle">The <see cref="Particle"/> to process.</param>
/// <param name="elapsedTime">The amount of time that has elapsed since the <paramref name="emitter"/>
/// was last updated.</param>
protected override void HandleProcessUpdated(ParticleEmitter emitter, Particle particle, int elapsedTime)
{
// Get the absolute position
Vector2 absolutePosition;
emitter.GetAbsoultePosition(ref _position, out absolutePosition);
// Get the distance from the particle
Vector2 distance;
Vector2.Subtract(ref absolutePosition, ref particle.Position, out distance);
// Check if the particle is in range
if (distance.LengthSquared() >= _radiusSquared)
{
return;
}
// Normalize the distance vector to get the force
Vector2 force;
Vector2.Normalize(ref distance, out force);
// Adjust the force by the strength and elapsed time
Vector2.Multiply(ref force, _strength * elapsedTime, out force);
// Apply the force to the particle
particle.ApplyForce(ref force);
}
public void Simulate(double dt)
{
if (dragging)
{
VectorN dragForce = new VectorN(2);
dragForce.v[0] = mousex - dragged.pos.v[0];
dragForce.v[1] = mousey - dragged.pos.v[1];
dragForce.Scale(50 * dragged.mass);
dragged.ApplyForce(dragForce);
dragged.Unfreeze();
}
for (int i = 0; i < particles.Count; i++)
{
if (particles[i] != dragged)
{
particles[i].ApplyGravity();
}
}
dynamics.SimulateFast(dt);
CheckBounds();
}
/// <summary>
/// Processes the specified Particle.
/// </summary>
public override void Process(float totalSeconds, float elapsedSeconds, ref Particle particle, object tag)
{
Vector2 deltaGrav;
Vector2.Multiply(ref this.Gravity, elapsedSeconds, out deltaGrav);
particle.ApplyForce(ref deltaGrav);
}
private float _strength; //Gravity strength in pixels per second.
/// <summary>
/// Processes an active particle.
/// </summary>
/// <param name="totalTime">Total game time in whole and fractional seconds.</param>
/// <param name="elapsedTime">Elapsed game time in whole and fractional seconds.</param>
/// <param name="particle">The particle to be updated.</param>
/// <param name="age">The age of the particle in the range of zero to one inclusive.</param>
public override void ProcessActiveParticle(float totalTime, float elapsedTime, ref Particle particle, float age)
{
Vector2 force = this._gravity;
Vector2.Multiply(ref force, this._strength * elapsedTime, out force);
particle.ApplyForce(ref force);
}
private float _coefficient; //The damping coefficient.
/// <summary>
/// Processes an active particle.
/// </summary>
/// <param name="totalTime">Total game time in whole and fractional seconds.</param>
/// <param name="elapsedTime">Elapsed game time in whole and fractional seconds.</param>
/// <param name="particle">The particle to be processed.</param>
/// <param name="age">The age of the particle in the range 0-1.</param>
public override void ProcessActiveParticle(float totalTime, float elapsedTime, ref Particle particle, float age)
{
Vector2 momentum = particle.Momentum;
Vector2.Multiply(ref momentum, this._coefficient, out momentum);
Vector2.Negate(ref momentum, out momentum);
particle.ApplyForce(ref momentum);
}
/// <summary>
/// Processes the specified Particle.
/// </summary>
public override void Process(float totalSeconds, float elapsedSeconds, ref Particle particle, object tag)
{
Vector2 distance;
// Calculate the distance between the Particle and the gravity well...
Vector2.Subtract(ref this.Position, ref particle.Position, out distance);
// Check to see if the Particle is within range of the gravity well...
if (distance.LengthSquared() < this.RadiusSquared)
{
Vector2 force;
// We can re-use the distance vector, and normalise it as the force vector...
Vector2.Normalize(ref distance, out force);
// Adjust the force vector based on the strength of the gravity well and the time delta...
Vector2.Multiply(ref force, this.Strength * elapsedSeconds, out force);
particle.ApplyForce(ref force);
}
}
void Update()
{
for (int i = 0; i < ParticlesCount; i++)
{
Particle particle = particles[i];
Vector3 position = particle.transform.position;
int x = Mathf.FloorToInt((position.x - (transform.position.x - size * 0.5f)) / size * resolution);
int y = Mathf.FloorToInt((position.y - (transform.position.y - size * 0.5f)) / size * resolution);
int z = Mathf.FloorToInt((position.z - (transform.position.z - size * 0.5f)) / size * resolution);
particle.ApplyForce(field[x, y, z] * 0.01f);
particle.Update();
if (particle.transform.position.x <= (transform.position.x - size * 0.5f) || particle.transform.position.x >= (transform.position.x + size * 0.5f) ||
particle.transform.position.y <= (transform.position.y - size * 0.5f) || particle.transform.position.y >= (transform.position.y + size * 0.5f) ||
particle.transform.position.z <= (transform.position.z - size * 0.5f) || particle.transform.position.z >= (transform.position.z + size * 0.5f))
{
particle.transform.position = NewPosition();
}
}
UpdateFlowField();
}
/// <summary>
/// When overridden in the derived class, handles processing the <paramref name="particle"/> when
/// it is updated. Only valid if <see cref="ParticleModifier.ProcessOnUpdate"/> is set.
/// </summary>
/// <param name="emitter">The <see cref="ParticleEmitter"/> that the <paramref name="particle"/>
/// came from.</param>
/// <param name="particle">The <see cref="Particle"/> to process.</param>
/// <param name="elapsedTime">The amount of time that has elapsed since the <paramref name="emitter"/>
/// was last updated.</param>
protected override void HandleProcessUpdated(ParticleEmitter emitter, Particle particle, int elapsedTime)
{
// Get the absolute position
Vector2 absolutePosition;
emitter.GetAbsoultePosition(ref _position, out absolutePosition);
// Get the distance from the particle
Vector2 distance;
Vector2.Subtract(ref absolutePosition, ref particle.Position, out distance);
// Check if the particle is in range
if (distance.LengthSquared() >= _radiusSquared)
return;
// Normalize the distance vector to get the force
Vector2 force;
Vector2.Normalize(ref distance, out force);
// Adjust the force by the strength and elapsed time
Vector2.Multiply(ref force, _strength * elapsedTime, out force);
// Apply the force to the particle
particle.ApplyForce(ref force);
}
public static void PhysicsString()
{
PhysicsManager mgr = new PhysicsManager();
Particle a = new Particle(1.0f)
{
IsAffectedByAirFriction = true
};
Particle b = new Particle(2.0f)
{
IsAffectedByAirFriction = true
};
StringJoint stringJ = new StringJoint(a, b, 1.0f, 100.0f, 0.15f);
mgr.PhysicsObjects.Add(a);
mgr.PhysicsObjects.Add(b);
mgr.PhysicsObjects.Add(stringJ);
a.Position = Game.LocalPlayer.Character.GetOffsetPosition(new Vector3(0f, 2.0f, 1.0f));
b.Position = Game.LocalPlayer.Character.GetOffsetPosition(new Vector3(0f, 3.25f, 1.0f));
Vector3 positionChange = new Vector3();
mgr.AfterSolve += () =>
{
if (positionChange != Vector3.Zero)
{
a.ApplyForce(positionChange);
}
};
while (true)
{
GameFiber.Yield();
positionChange = new Vector3();
const float moveValue = 25f;
if (Game.IsKeyDownRightNow(Keys.NumPad6))
{
positionChange.X += moveValue;
}
if (Game.IsKeyDownRightNow(Keys.NumPad4))
{
positionChange.X -= moveValue;
}
if (Game.IsKeyDownRightNow(Keys.NumPad8))
{
positionChange.Y -= moveValue;
}
if (Game.IsKeyDownRightNow(Keys.NumPad2))
{
positionChange.Y += moveValue;
}
if (Game.IsKeyDownRightNow(Keys.NumPad9))
{
positionChange.Z += moveValue;
}
if (Game.IsKeyDownRightNow(Keys.NumPad3))
{
positionChange.Z -= moveValue;
}
mgr.Update();
}
}
/// <summary>
/// Processes an active particle.
/// </summary>
/// <param name="totalTime">Total game time in whole and fractional seconds.</param>
/// <param name="elapsedTime">Elapsed game time in whole and fractional seconds.</param>
/// <param name="particle">The particle which is ready to be processed.</param>
/// <param name="age">The age of the particle in the range 0-1.</param>
public override void ProcessActiveParticle(float totalTime, float elapsedTime, ref Particle particle, float age)
{
float distance;
Vector2.DistanceSquared(ref this._position, ref particle.Position, out distance);
if (distance < this._radiusSq)
{
float effect = 1f - (distance / this._radiusSq);
Vector2 force;
Vector2.Subtract(ref this._position, ref particle.Position, out force);
Vector2.Normalize(ref force, out force);
Vector2.Transform(ref force, ref this._rotation, out force);
Vector2.Multiply(ref force, effect * elapsedTime * this._vorticity, out force);
particle.ApplyForce(ref force);
}
}