internal void DoDamping()
{
if (bodyID == dBodyID.Zero)
{
return;
}
Ode.dMass mass = new Ode.dMass();
Ode.dBodyGetMass(bodyID, ref mass);
// Linear damping
if (LinearDamping != 0)
{
// The damping force depends on the damping amount, mass, and velocity
// (i.e. damping amount and momentum).
float factor = -LinearDamping * mass.mass;
Vec3 force = LinearVelocity * factor;
// Add a global force opposite to the global linear velocity.
Ode.dBodyAddForce(bodyID, force.X, force.Y, force.Z);
}
// Angular damping
if (AngularDamping != 0)
{
Vec3 localVelocity;
{
Ode.dVector3 aVelLocal = new Ode.dVector3();
Ode.dBodyVectorFromWorld(bodyID, AngularVelocity.X, AngularVelocity.Y,
AngularVelocity.Z, ref aVelLocal);
localVelocity = Convert.ToNet(aVelLocal);
}
// The damping force depends on the damping amount, mass, and velocity
// (i.e. damping amount and momentum).
float factor = -AngularDamping;
Vec3 momentum = new Vec3(
Vec3.Dot(new Vec3(mass.I.M00, mass.I.M01, mass.I.M02), localVelocity),
Vec3.Dot(new Vec3(mass.I.M10, mass.I.M11, mass.I.M12), localVelocity),
Vec3.Dot(new Vec3(mass.I.M20, mass.I.M21, mass.I.M22), localVelocity));
Vec3 torque = momentum * factor;
// Add a local torque opposite to the local angular velocity.
Ode.dBodyAddRelTorque(bodyID, torque.X, torque.Y, torque.Z);
}
}