Function d3_geo_clip

explainshell/web/static/js/d3.v3.js:2350–2438

(pointVisible, clipLine, interpolate)

    b.prev = a;
  }
  function d3_geo_clip(pointVisible, clipLine, interpolate) {
    return function(listener) {
      var line = clipLine(listener);
      var clip = {
        point: point,
        lineStart: lineStart,
        lineEnd: lineEnd,
        polygonStart: function() {
          clip.point = pointRing;
          clip.lineStart = ringStart;
          clip.lineEnd = ringEnd;
          invisible = false;
          invisibleArea = visibleArea = 0;
          segments = [];
          listener.polygonStart();
        },
        polygonEnd: function() {
          clip.point = point;
          clip.lineStart = lineStart;
          clip.lineEnd = lineEnd;
          segments = d3.merge(segments);
          if (segments.length) {
            d3_geo_clipPolygon(segments, d3_geo_clipSort, null, interpolate, listener);
          } else if (visibleArea < -ε || invisible && invisibleArea < -ε) {
            listener.lineStart();
            interpolate(null, null, 1, listener);
            listener.lineEnd();
          }
          listener.polygonEnd();
          segments = null;
        },
        sphere: function() {
          listener.polygonStart();
          listener.lineStart();
          interpolate(null, null, 1, listener);
          listener.lineEnd();
          listener.polygonEnd();
        }
      };
      function point(λ, φ) {
        if (pointVisible(λ, φ)) listener.point(λ, φ);
      }
      function pointLine(λ, φ) {
        line.point(λ, φ);
      }
      function lineStart() {
        clip.point = pointLine;
        line.lineStart();
      }
      function lineEnd() {
        clip.point = point;
        line.lineEnd();
      }
      var segments, visibleArea, invisibleArea, invisible;
      var buffer = d3_geo_clipBufferListener(), ringListener = clipLine(buffer), ring;
      function pointRing(λ, φ) {
        ringListener.point(λ, φ);
        ring.push([ λ, φ ]);