Function extractArcs

docs/tests/v2/es6/js/sanddance.js:80563–80616

(topology, object, filter)

}

function extractArcs(topology, object, filter) {
  var arcs = [],
      geomsByArc = [],
      geom;

  function extract0(i) {
    var j = i < 0 ? ~i : i;
    (geomsByArc[j] || (geomsByArc[j] = [])).push({
      i: i,
      g: geom
    });
  }

  function extract1(arcs) {
    arcs.forEach(extract0);
  }

  function extract2(arcs) {
    arcs.forEach(extract1);
  }

  function extract3(arcs) {
    arcs.forEach(extract2);
  }

  function geometry(o) {
    switch (geom = o, o.type) {
      case "GeometryCollection":
        o.geometries.forEach(geometry);
        break;

      case "LineString":
        extract1(o.arcs);
        break;

      case "MultiLineString":
      case "Polygon":
        extract2(o.arcs);
        break;

      case "MultiPolygon":
        extract3(o.arcs);
        break;
    }
  }

  geometry(object);
  geomsByArc.forEach(filter == null ? function (geoms) {
    arcs.push(geoms[0].i);
  } : function (geoms) {
    if (filter(geoms[0].g, geoms[geoms.length - 1].g)) arcs.push(geoms[0].i);
  });
  return arcs;
}
},{"./feature.js":"FNho","./stitch.js":"ycfC"}],"vI6u":[function(require,module,exports) {
"use strict";