src/main/webapp/resources/js/data-map/topojson.js

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!function() {
    var topojson = {
        version: "1.6.20",
        mesh: function(topology) { return object(topology, meshArcs.apply(this, arguments)); },
        meshArcs: meshArcs,
        merge: function(topology) { return object(topology, mergeArcs.apply(this, arguments)); },
        mergeArcs: mergeArcs,
        feature: featureOrCollection,
        neighbors: neighbors,
        presimplify: presimplify
    };

    function stitchArcs(topology, arcs) {
        var stitchedArcs = {},
            fragmentByStart = {},
            fragmentByEnd = {},
            fragments = [],
            emptyIndex = -1;

        // Stitch empty arcs first, since they may be subsumed by other arcs.
        arcs.forEach(function(i, j) {
            var arc = topology.arcs[i < 0 ? ~i : i], t;
            if (arc.length < 3 && !arc[1][0] && !arc[1][1]) {
                t = arcs[++emptyIndex], arcs[emptyIndex] = i, arcs[j] = t;
            }
        });

        arcs.forEach(function(i) {
            var e = ends(i),
                start = e[0],
                end = e[1],
                f, g;

            if (f = fragmentByEnd[start]) {
                delete fragmentByEnd[f.end];
                f.push(i);
                f.end = end;
                if (g = fragmentByStart[end]) {
                    delete fragmentByStart[g.start];
                    var fg = g === f ? f : f.concat(g);
                    fragmentByStart[fg.start = f.start] = fragmentByEnd[fg.end = g.end] = fg;
                } else {
                    fragmentByStart[f.start] = fragmentByEnd[f.end] = f;
                }
            } else if (f = fragmentByStart[end]) {
                delete fragmentByStart[f.start];
                f.unshift(i);
                f.start = start;
                if (g = fragmentByEnd[start]) {
                    delete fragmentByEnd[g.end];
                    var gf = g === f ? f : g.concat(f);
                    fragmentByStart[gf.start = g.start] = fragmentByEnd[gf.end = f.end] = gf;
                } else {
                    fragmentByStart[f.start] = fragmentByEnd[f.end] = f;
                }
            } else {
                f = [i];
                fragmentByStart[f.start = start] = fragmentByEnd[f.end = end] = f;
            }
        });