Function insertChild

explainshell/web/static/js/d3.v3.js:4560–4567

(n, d, x, y, x1, y1, x2, y2)

        }
      }
      function insertChild(n, d, x, y, x1, y1, x2, y2) {
        var sx = (x1 + x2) * .5, sy = (y1 + y2) * .5, right = x >= sx, bottom = y >= sy, i = (bottom << 1) + right;
        n.leaf = false;
        n = n.nodes[i] || (n.nodes[i] = d3_geom_quadtreeNode());
        if (right) x1 = sx; else x2 = sx;
        if (bottom) y1 = sy; else y2 = sy;
        insert(n, d, x, y, x1, y1, x2, y2);
      }
      var root = d3_geom_quadtreeNode();
      root.add = function(d) {
        insert(root, d, +fx(d, ++i), +fy(d, i), x1_, y1_, x2_, y2_);