Hi everyone. I'm doing my class project and i'm having troubles with Euler integration (witch seems to be the basic)...
The main loop:


torque = position.cross(force);

momentum += dt * force;
//velocity = momentum * (1.0f / mass);

position += velocity * dt;

ang_momentum += torque * dt;
m_inertia_inverse = MakeMatrixFromQuaternion(orientation).transpose() * g_inertia * MakeMatrixFromQuaternion(orientation);
ang_vel = multvm(ang_momentum, m_inertia_inverse); //multiplies a vector by a matrix

orientation += (Quaternion(0, ang_vel.x, ang_vel.y, ang_vel.z) * orientation) * (0.5f * dt);
orientation.normalize();

"g_inertia" is the following matrix3

inertia.m31 = 0; inertia.m32 = 0; inertia.m33 = Iz;

and i'm rotating like this:

The code is right?

Seems like i'm having trouble with the numbers. They out of range... especially with the angular velocity!

someone have a similar code ???

m_inertia_inverse = MakeMatrixFromQuaternion(orientation).transpose() * g_inertia * MakeMatrixFromQuaternion(orientation);

Would this work?

m_inertia_inverse = MakeMatrixFromQuaternion(orientation).transpose() * g_inertia.Inverse() * MakeMatrixFromQuaternion(orientation);

m_inertia_inverse = MakeMatrixFromQuaternion(orientation).transpose() * g_inertia * MakeMatrixFromQuaternion(orientation);

Would this work?

m_inertia_inverse = MakeMatrixFromQuaternion(orientation).transpose() * g_inertia.Inverse() * MakeMatrixFromQuaternion(orientation);

thanks but i've already done this in the constructor

torque = position.cross(force);

What about:

r = some point on sphere - sphere position;

torque = r.cross( force );

torque = position.cross(force);

What about:

r = some point on sphere - sphere position;

torque = r.cross( force );

thanks but the only force that actually i have, is the gravity force that is on the constructor ,,,