1.  slow down to arrive at goal point

    const vec3 desired = dest - position();
    const vec3 steering_force = desired - velocity();

// from above formula we know : the character does slow down its speed to try 
// to arrive at goal point

    
2.  run around goal point unstoppably 
    const vec3 desired = dest - position();
    const vec3 steering_force = max_force * normal(desired);

// from above code we see the character will never reach its goal unless
// character's velocity is almost co-line with the desired direction.

desired = dest - positionsteer = desired - velocityif (max_braking_dist - desired.length <= 0)returnsteer *= max_braking_dist / (max_braking_dist - desired.length)