Function score

external/.d3.js:13444–13451

(node)

}

function score(node) {
  var a = node._,
      b = node.next._,
      ab = a.r + b.r,
      dx = (a.x * b.r + b.x * a.r) / ab,
      dy = (a.y * b.r + b.y * a.r) / ab;
  return dx * dx + dy * dy;
}

function Node(circle) {
  this._ = circle;