public virtual void UpdateForce(T2DPhysicsComponent physics, float strength, Vector2 offset, Vector2 direction, float dt)
{
strength = strength * (MaxStrength - MinStrength) + MinStrength;
// will be modified by inverse mass (and inverse rot inertia)
physics.ApplyImpulse(-direction * strength * dt, offset);
}
public override void UpdateForce(T2DPhysicsComponent physics, float strength, Vector2 offset, Vector2 direction, float dt)
{
strength = strength * (MaxStrength - MinStrength) + MinStrength;
if (offset.LengthSquared() < 0.0001f || physics.Immovable)
// skip the mass route -- will work on immovable
physics.Velocity -= direction * strength * dt;
else
// have to use real impulse, multiply by mass
physics.ApplyImpulse(-direction * strength * physics.Mass * dt, offset);
}
protected void _ApplyDrag(Vector2 vel, T2DPhysicsComponent physics, float strength, float rotStrength, Vector2 offset, Vector2 direction, float dt)
{
// adjust rotation velocity based on rotation drag
if (rotStrength < 0.0f)
// handle case where negative force is set
rotStrength = 0.0f;
if (!ConstantDrag)
rotStrength *= Math.Abs(physics.AngularVelocity);
if (rotStrength > AbsoluteDragRotationCap)
rotStrength = AbsoluteDragFactor * AbsoluteDragRotationCap;
rotStrength *= dt;
if (rotStrength > Math.Abs(physics.AngularVelocity))
physics.AngularVelocity = 0.0f;
else if (physics.AngularVelocity > 0.0f)
physics.AngularVelocity -= rotStrength;
else
physics.AngularVelocity += rotStrength;
float velLen = vel.Length();
if (velLen > Epsilon.Value)
vel.Normalize();
// adjust by velocity and update interval
if (!ConstantDrag)
strength *= velLen;
if (strength > AbsoluteDragCap)
strength = AbsoluteDragFactor * AbsoluteDragCap;
strength *= dt;
// make sure we don't overshoot
if (strength > velLen)
strength = velLen;
if (!physics.Immovable)
physics.ApplyImpulse(-strength * vel * physics.Mass, offset);
else
physics.Velocity -= strength * vel;
}