pod = {
const pod = d3ForcePod()(domEl)
.nodeColor(({ pole }) => COLORS[pole > 0 ? 'attractive' : 'repellent']);
pod.addForce(d3.forceBounce()
.radius(d => d.r)
.elasticity(0)
);
pod.addForce(d3.forceMagnetic()
.charge(node => node.pole * node.r * node.r)
.strength(ACCELERATION_K)
);
return pod;
}