protected void makeTessellatedLocations(
      Globe globe, int subdivisions, List<LatLon> locations, List<LatLon> tessellatedLocations) {
    ArrayList<Vec4> points = new ArrayList<Vec4>();
    for (LatLon ll : locations) {
      points.add(globe.computePointFromLocation(ll));
    }

    //noinspection StringEquality
    if (WWMath.computeWindingOrderOfLocations(locations) != AVKey.COUNTER_CLOCKWISE)
      Collections.reverse(locations);

    Vec4 centerPoint = Vec4.computeAveragePoint(points);
    Vec4 surfaceNormal = globe.computeSurfaceNormalAtPoint(centerPoint);

    int numPoints = points.size();
    float[] coords = new float[3 * numPoints];
    for (int i = 0; i < numPoints; i++) {
      points.get(i).toFloatArray(coords, 3 * i, 3);
    }

    GeometryBuilder gb = new GeometryBuilder();
    GeometryBuilder.IndexedTriangleArray tessellatedPoints =
        gb.tessellatePolygon(0, numPoints, coords, surfaceNormal);

    for (int i = 0; i < subdivisions; i++) {
      gb.subdivideIndexedTriangleArray(tessellatedPoints);
    }

    for (int i = 0; i < tessellatedPoints.getVertexCount(); i++) {
      Vec4 v = Vec4.fromFloatArray(tessellatedPoints.getVertices(), 3 * i, 3);
      tessellatedLocations.add(globe.computePositionFromPoint(v));
    }
  }
  protected Extent computeExtent(Globe globe, double verticalExaggeration) {
    List<Vec4> points = this.computeMinimalGeometry(globe, verticalExaggeration);
    if (points == null || points.isEmpty()) return null;

    // Add a point at the center of this polygon to the points used to compute its extent. The
    // center point captures
    // the curvature of the globe when the polygon's minimal geometry only contain any points near
    // the polygon's
    // edges.
    Vec4 centerPoint = Vec4.computeAveragePoint(points);
    LatLon centerLocation = globe.computePositionFromPoint(centerPoint);
    this.makeExtremePoints(globe, verticalExaggeration, Arrays.asList(centerLocation), points);

    return Box.computeBoundingBox(points);
  }
  protected int computeCartesianPolygon(
      Globe globe,
      List<? extends LatLon> locations,
      List<Boolean> edgeFlags,
      Vec4[] points,
      Boolean[] edgeFlagArray,
      Matrix[] transform) {
    if (globe == null) {
      String message = Logging.getMessage("nullValue.GlobeIsNull");
      Logging.logger().severe(message);
      throw new IllegalArgumentException(message);
    }
    if (locations == null) {
      String message = "nullValue.LocationsIsNull";
      Logging.logger().severe(message);
      throw new IllegalArgumentException(message);
    }
    if (points == null) {
      String message = "nullValue.LocationsIsNull";
      Logging.logger().severe(message);
      throw new IllegalArgumentException(message);
    }
    if (points.length < (1 + locations.size())) {
      String message =
          Logging.getMessage(
              "generic.ArrayInvalidLength", "points.length < " + (1 + locations.size()));
      Logging.logger().severe(message);
      throw new IllegalArgumentException(message);
    }
    if (transform == null) {
      String message = "nullValue.TransformIsNull";
      Logging.logger().severe(message);
      throw new IllegalArgumentException(message);
    }
    if (transform.length < 1) {
      String message = Logging.getMessage("generic.ArrayInvalidLength", "transform.length < 1");
      Logging.logger().severe(message);
      throw new IllegalArgumentException(message);
    }

    // Allocate space to hold the list of locations and location vertices.
    int locationCount = locations.size();

    // Compute the cartesian points for each location.
    for (int i = 0; i < locationCount; i++) {
      LatLon ll = locations.get(i);
      points[i] = globe.computePointFromPosition(ll.getLatitude(), ll.getLongitude(), 0.0);

      if (edgeFlagArray != null) edgeFlagArray[i] = (edgeFlags != null) ? edgeFlags.get(i) : true;
    }

    // Compute the average of the cartesian points.
    Vec4 centerPoint = Vec4.computeAveragePoint(Arrays.asList(points));

    // Test whether the polygon is closed. If it is not closed, repeat the first vertex.
    if (!points[0].equals(points[locationCount - 1])) {
      points[locationCount] = points[0];
      if (edgeFlagArray != null) edgeFlagArray[locationCount] = edgeFlagArray[0];

      locationCount++;
    }

    // Compute a transform that will map the cartesian points to a local coordinate system centered
    // at the average
    // of the points and oriented with the globe surface.
    Position centerPos = globe.computePositionFromPoint(centerPoint);
    Matrix tx = globe.computeSurfaceOrientationAtPosition(centerPos);
    Matrix txInv = tx.getInverse();
    // Map the cartesian points to a local coordinate space.
    for (int i = 0; i < locationCount; i++) {
      points[i] = points[i].transformBy4(txInv);
    }

    transform[0] = tx;

    return locationCount;
  }