// update force vector arrows
        for (int i = 0; i < NUM_SPHERES; i++){
            cVector3d newPoint = cAdd(spheres[i]->getLocalPos(), sphereFce[i]);
            cVector3d newPointNormalized;
            sphereFce[i].normalizer(newPointNormalized);
            velVectors[i]->m_pointA = cAdd(spheres[i]->getLocalPos(), newPointNormalized * spheres[i]->getRadius());
            velVectors[i]->m_pointB = cAdd(velVectors[i]->m_pointA, sphereFce[i] * .05);
            velVectors[i]->setLineWidth(5);

            // Change color, red if current, black otherwise
            if (i == curr_atom) {
                velVectors[i]->m_colorPointA.setRed();
                velVectors[i]->m_colorPointB.setRed();
            } else {
                velVectors[i]->m_colorPointA.setBlack();
                velVectors[i]->m_colorPointB.setBlack();
            }

            // Change size based on threshold?
            float dist = velVectors[i]->m_pointA.distance(velVectors[i]->m_pointB);
            if (dist >= .05 ){
                velVectors[i]->m_pointB = cAdd(velVectors[i]->m_pointA, newPointNormalized * .05);
            }
            // TODO - use distance to set some kind of threshold that will scale down any large lines
            // code below is a remmant from using velocity
            /*
            if (i == curr_atom) {
                velVectors[i]->m_pointB = cAdd(spheres[i]->getLocalPos(), linearVelocity);
            } else {
                velVectors[i]->m_pointB = cAdd(spheres[i]->getLocalPos(), sphereFce[i]);
                //velVectors[i]->m_pointB = cAdd(spheres[i]->getLocalPos(),
                //                            sphereVel[i] * -500);
            } */
        }