JESSICA BARON

 //--------------------------------------
 pba::Vector calcTotalAccel(pba::DynamicalState &state, int boidID)
    {
      //Vectors initialized as (0,0,0).
        pba::Vector d, totalAccel, avoidAccel, velAccel, centerAccel;
        int count, other;
        double rangeWeight, visibility, residual;     //Used in keeping total accel under max accel.

        count = state->nb();
        for(other=0; other<count; other++)
        {
            if (other != boidID)
            {
                d = state->pos(other) - state->pos(boidID);
                rangeWeight = calcRangeWeight( d.magnitude() );
                visibility = calcVisibilityWeight( d, state->vel(boidID) );

                avoidAccel += calcCollisionAvoidance(state,
                            boidID, other, rangeWeight, visibility);
                velAccel += calcVelocityMatching(state,
                            boidID, other, rangeWeight, visibility);
                centerAccel += calcCentering(state,
                            boidID, other, rangeWeight, visibility);
            }
        }


      //Modifier to boids: Limit the acceleration.
        if ( avoidAccel.magnitude() > maxAccel )
        {
            avoidAccel = avoidAccel * (maxAccel / avoidAccel.magnitude());    //Scale down magnitude to maxAccel.
            velAccel.set(0,0,0);         //Already maxed out the total accel, so set these to 0 vectors.
            centerAccel.set(0,0,0);
        }
        else
        {
            residual = maxAccel - avoidAccel.magnitude();   //New threshold for the other accels to stay below.
            if ( velAccel.magnitude() > residual )
            {
                velAccel = velAccel * (residual / velAccel.magnitude());
                centerAccel.set(0,0,0);
            }
            else
            {
                residual = residual - velAccel.magnitude();
                if ( centerAccel.magnitude() > residual )
                {
                    centerAccel = centerAccel * (residual / centerAccel.magnitude());
                }
            }
        }

        totalAccel = avoidAccel + velAccel + centerAccel;
        return totalAccel;
    }