function d3_geom_voronoiAddBeach()

in TestApplications/Web/js/lib/components/d3-3.4.13/src/geom/voronoi/beach.js [76:152]

• 68 lines of code
• 11 McCabe index (conditional complexity)

function d3_geom_voronoiAddBeach(site) {
  var x = site.x,
      directrix = site.y,
      lArc,
      rArc,
      dxl,
      dxr,
      node = d3_geom_voronoiBeaches._;

  while (node) {
    dxl = d3_geom_voronoiLeftBreakPoint(node, directrix) - x;
    if (dxl > ε) node = node.L; else {
      dxr = x - d3_geom_voronoiRightBreakPoint(node, directrix);
      if (dxr > ε) {
        if (!node.R) {
          lArc = node;
          break;
        }
        node = node.R;
      } else {
        if (dxl > -ε) {
          lArc = node.P;
          rArc = node;
        } else if (dxr > -ε) {
          lArc = node;
          rArc = node.N;
        } else {
          lArc = rArc = node;
        }
        break;
      }
    }
  }

  var newArc = d3_geom_voronoiCreateBeach(site);
  d3_geom_voronoiBeaches.insert(lArc, newArc);

  if (!lArc && !rArc) return;

  if (lArc === rArc) {
    d3_geom_voronoiDetachCircle(lArc);
    rArc = d3_geom_voronoiCreateBeach(lArc.site);
    d3_geom_voronoiBeaches.insert(newArc, rArc);
    newArc.edge = rArc.edge = d3_geom_voronoiCreateEdge(lArc.site, newArc.site);
    d3_geom_voronoiAttachCircle(lArc);
    d3_geom_voronoiAttachCircle(rArc);
    return;
  }

  if (!rArc) { // && lArc
    newArc.edge = d3_geom_voronoiCreateEdge(lArc.site, newArc.site);
    return;
  }

  // else lArc !== rArc
  d3_geom_voronoiDetachCircle(lArc);
  d3_geom_voronoiDetachCircle(rArc);

  var lSite = lArc.site,
      ax = lSite.x,
      ay = lSite.y,
      bx = site.x - ax,
      by = site.y - ay,
      rSite = rArc.site,
      cx = rSite.x - ax,
      cy = rSite.y - ay,
      d = 2 * (bx * cy - by * cx),
      hb = bx * bx + by * by,
      hc = cx * cx + cy * cy,
      vertex = {x: (cy * hb - by * hc) / d + ax, y: (bx * hc - cx * hb) / d + ay};

  d3_geom_voronoiSetEdgeEnd(rArc.edge, lSite, rSite, vertex);
  newArc.edge = d3_geom_voronoiCreateEdge(lSite, site, null, vertex);
  rArc.edge = d3_geom_voronoiCreateEdge(site, rSite, null, vertex);
  d3_geom_voronoiAttachCircle(lArc);
  d3_geom_voronoiAttachCircle(rArc);
}