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:

Is the code right? i've spend 5 days trying to solve it but i think is a little problem and i can't see

Seems like i'm having trouble with the numbers... they are large, especially with the angular velocity...