public int countImagesInSector(Sector sector, int levelNumber) {
    if (sector == null) {
      String msg = Logging.getMessage("nullValue.SectorIsNull");
      Logging.logger().severe(msg);
      throw new IllegalArgumentException(msg);
    }

    Level targetLevel = this.levels.getLastLevel();
    if (levelNumber >= 0) {
      for (int i = levelNumber; i < this.getLevels().getLastLevel().getLevelNumber(); i++) {
        if (this.levels.isLevelEmpty(i)) continue;

        targetLevel = this.levels.getLevel(i);
        break;
      }
    }

    // Collect all the tiles intersecting the input sector.
    LatLon delta = targetLevel.getTileDelta();
    Angle latOrigin = this.levels.getTileOrigin().getLatitude();
    Angle lonOrigin = this.levels.getTileOrigin().getLongitude();
    final int nwRow = Tile.computeRow(delta.getLatitude(), sector.getMaxLatitude(), latOrigin);
    final int nwCol = Tile.computeColumn(delta.getLongitude(), sector.getMinLongitude(), lonOrigin);
    final int seRow = Tile.computeRow(delta.getLatitude(), sector.getMinLatitude(), latOrigin);
    final int seCol = Tile.computeColumn(delta.getLongitude(), sector.getMaxLongitude(), lonOrigin);

    int numRows = nwRow - seRow + 1;
    int numCols = seCol - nwCol + 1;

    return numRows * numCols;
  }
  protected static boolean isSectorVisible(
      DrawContext dc, Sector sector, double minDistanceSquared, double maxDistanceSquared) {

    View view = dc.getView();
    Position eyePos = view.getEyePosition();
    if (eyePos == null) return false;

    Angle lat = clampAngle(eyePos.getLatitude(), sector.getMinLatitude(), sector.getMaxLatitude());
    Angle lon =
        clampAngle(eyePos.getLongitude(), sector.getMinLongitude(), sector.getMaxLongitude());
    Vec4 p = dc.getGlobe().computePointFromPosition(lat, lon, 0d);
    double distSquared = dc.getView().getEyePoint().distanceToSquared3(p);
    //noinspection RedundantIfStatement
    if (minDistanceSquared > distSquared || maxDistanceSquared < distSquared) return false;

    return true;
  }
  protected int determineAdjustmentSide(Movable dragObject, double factor) {
    if (dragObject instanceof SurfaceSector) {
      SurfaceSector quad = (SurfaceSector) dragObject;
      Sector s = quad.getSector(); // TODO: go over all sectors
      Position p = this.getWwd().getCurrentPosition();

      if (p == null) {
        return NONE;
      }

      double dN = abs(s.getMaxLatitude().subtract(p.getLatitude()).degrees);
      double dS = abs(s.getMinLatitude().subtract(p.getLatitude()).degrees);
      double dW = abs(s.getMinLongitude().subtract(p.getLongitude()).degrees);
      double dE = abs(s.getMaxLongitude().subtract(p.getLongitude()).degrees);

      double sLat = factor * s.getDeltaLatDegrees();
      double sLon = factor * s.getDeltaLonDegrees();

      if (dN < sLat && dW < sLon) return NORTHWEST;
      if (dN < sLat && dE < sLon) return NORTHEAST;
      if (dS < sLat && dW < sLon) return SOUTHWEST;
      if (dS < sLat && dE < sLon) return SOUTHEAST;
      if (dN < sLat) return NORTH;
      if (dS < sLat) return SOUTH;
      if (dW < sLon) return WEST;
      if (dE < sLon) return EAST;
    }

    return NONE;
  }
  private MercatorTextureTile[][] getTilesInSector(Sector sector, int levelNumber) {
    if (sector == null) {
      String msg = Logging.getMessage("nullValue.SectorIsNull");
      Logging.logger().severe(msg);
      throw new IllegalArgumentException(msg);
    }

    Level targetLevel = this.levels.getLastLevel();
    if (levelNumber >= 0) {
      for (int i = levelNumber; i < this.getLevels().getLastLevel().getLevelNumber(); i++) {
        if (this.levels.isLevelEmpty(i)) continue;

        targetLevel = this.levels.getLevel(i);
        break;
      }
    }

    // Collect all the tiles intersecting the input sector.
    LatLon delta = targetLevel.getTileDelta();
    Angle latOrigin = this.levels.getTileOrigin().getLatitude();
    Angle lonOrigin = this.levels.getTileOrigin().getLongitude();
    final int nwRow = Tile.computeRow(delta.getLatitude(), sector.getMaxLatitude(), latOrigin);
    final int nwCol = Tile.computeColumn(delta.getLongitude(), sector.getMinLongitude(), lonOrigin);
    final int seRow = Tile.computeRow(delta.getLatitude(), sector.getMinLatitude(), latOrigin);
    final int seCol = Tile.computeColumn(delta.getLongitude(), sector.getMaxLongitude(), lonOrigin);

    int numRows = nwRow - seRow + 1;
    int numCols = seCol - nwCol + 1;
    MercatorTextureTile[][] sectorTiles = new MercatorTextureTile[numRows][numCols];

    for (int row = nwRow; row >= seRow; row--) {
      for (int col = nwCol; col <= seCol; col++) {
        TileKey key =
            new TileKey(targetLevel.getLevelNumber(), row, col, targetLevel.getCacheName());
        Sector tileSector = this.levels.computeSectorForKey(key);
        MercatorSector mSector = MercatorSector.fromSector(tileSector); // TODO: check
        sectorTiles[nwRow - row][col - nwCol] =
            new MercatorTextureTile(mSector, targetLevel, row, col);
      }
    }

    return sectorTiles;
  }
    protected void performIntersectionTests(final Position curPos) throws InterruptedException {
      // Clear the results lists when the user selects a new location.
      this.firstIntersectionPositions.clear();
      this.sightLines.clear();

      // Raise the selected location and the grid points a little above ground just to show we can.
      final double height = 5; // meters

      // Form the grid.
      double gridRadius = GRID_RADIUS.degrees;
      Sector sector =
          Sector.fromDegrees(
              curPos.getLatitude().degrees - gridRadius, curPos.getLatitude().degrees + gridRadius,
              curPos.getLongitude().degrees - gridRadius,
                  curPos.getLongitude().degrees + gridRadius);

      this.grid = buildGrid(sector, height, GRID_DIMENSION, GRID_DIMENSION);
      this.numGridPoints = grid.size();

      // Compute the position of the selected location (incorporate its height).
      this.referencePosition = new Position(curPos.getLatitude(), curPos.getLongitude(), height);
      this.referencePoint =
          terrain.getSurfacePoint(curPos.getLatitude(), curPos.getLongitude(), height);

      //            // Pre-caching is unnecessary and is useful only when it occurs before the
      // intersection
      //            // calculations. It will incur extra overhead otherwise. The normal intersection
      // calculations
      //            // cause the same caching, making subsequent calculations on the same area
      // faster.
      //            this.preCache(grid, this.referencePosition);

      // On the EDT, show the grid.
      SwingUtilities.invokeLater(
          new Runnable() {
            public void run() {
              progressBar.setValue(0);
              progressBar.setString(null);
              clearLayers();
              showGrid(grid, referencePosition);
              getWwd().redraw();
            }
          });

      // Perform the intersection calculations.
      this.startTime = System.currentTimeMillis();
      for (Position gridPos : this.grid) // for each grid point.
      {
        //noinspection ConstantConditions
        if (NUM_THREADS > 0) this.threadPool.execute(new Intersector(gridPos));
        else performIntersection(gridPos);
      }
    }
  private boolean needToSplit(DrawContext dc, Sector sector) {
    Vec4[] corners = sector.computeCornerPoints(dc.getGlobe(), dc.getVerticalExaggeration());
    Vec4 centerPoint = sector.computeCenterPoint(dc.getGlobe(), dc.getVerticalExaggeration());

    View view = dc.getView();
    double d1 = view.getEyePoint().distanceTo3(corners[0]);
    double d2 = view.getEyePoint().distanceTo3(corners[1]);
    double d3 = view.getEyePoint().distanceTo3(corners[2]);
    double d4 = view.getEyePoint().distanceTo3(corners[3]);
    double d5 = view.getEyePoint().distanceTo3(centerPoint);

    double minDistance = d1;
    if (d2 < minDistance) minDistance = d2;
    if (d3 < minDistance) minDistance = d3;
    if (d4 < minDistance) minDistance = d4;
    if (d5 < minDistance) minDistance = d5;

    double cellSize =
        (Math.PI * sector.getDeltaLatRadians() * dc.getGlobe().getRadius()) / 20; // TODO

    return !(Math.log10(cellSize) <= (Math.log10(minDistance) - this.splitScale));
  }
    protected boolean isNavSectorVisible(
        DrawContext dc, double minDistanceSquared, double maxDistanceSquared) {
      if (!navSector.intersects(dc.getVisibleSector())) return false;

      View view = dc.getView();
      Position eyePos = view.getEyePosition();
      if (eyePos == null) return false;

      // check for eyePos over globe
      if (Double.isNaN(eyePos.getLatitude().getDegrees())
          || Double.isNaN(eyePos.getLongitude().getDegrees())) return false;

      Angle lat =
          clampAngle(eyePos.getLatitude(), navSector.getMinLatitude(), navSector.getMaxLatitude());
      Angle lon =
          clampAngle(
              eyePos.getLongitude(), navSector.getMinLongitude(), navSector.getMaxLongitude());
      Vec4 p = dc.getGlobe().computePointFromPosition(lat, lon, 0d);
      double distSquared = dc.getView().getEyePoint().distanceToSquared3(p);
      //noinspection RedundantIfStatement
      if (minDistanceSquared > distSquared || maxDistanceSquared < distSquared) return false;

      return true;
    }
    @Override
    public void render(DrawContext dc) {
      if (dc.isPickingMode() && this.isResizeable()) return;

      // This is called twice: once during normal rendering, then again during ordered surface
      // rendering. During
      // normal renering we render both the interior and border shapes. During ordered surface
      // rendering, both
      // shapes are already added to the DrawContext and both will be individually processed.
      // Therefore we just
      // call our superclass behavior
      if (dc.isOrderedRenderingMode()) {
        super.render(dc);
        return;
      }

      if (!this.isResizeable()) {
        if (this.hasSelection()) {
          this.doRender(dc);
        }
        return;
      }

      PickedObjectList pos = dc.getPickedObjects();
      PickedObject terrainObject = pos != null ? pos.getTerrainObject() : null;

      if (terrainObject == null) return;

      if (this.getStartPosition() != null) {
        Position end = terrainObject.getPosition();
        if (!this.getStartPosition().equals(end)) {
          this.setEndPosition(end);
          this.setSector(Sector.boundingSector(this.getStartPosition(), this.getEndPosition()));
          this.doRender(dc);
        }
      } else {
        this.setStartPosition(pos.getTerrainObject().getPosition());
      }
    }
    protected List<Position> buildGrid(Sector sector, double height, int nLatCells, int nLonCells) {
      List<Position> grid = new ArrayList<Position>((nLatCells + 1) * (nLonCells + 1));

      double dLat = sector.getDeltaLatDegrees() / nLatCells;
      double dLon = sector.getDeltaLonDegrees() / nLonCells;

      for (int j = 0; j <= nLatCells; j++) {
        double lat =
            j == nLatCells
                ? sector.getMaxLatitude().degrees
                : sector.getMinLatitude().degrees + j * dLat;

        for (int i = 0; i <= nLonCells; i++) {
          double lon =
              i == nLonCells
                  ? sector.getMaxLongitude().degrees
                  : sector.getMinLongitude().degrees + i * dLon;

          grid.add(Position.fromDegrees(lat, lon, height));
        }
      }

      return grid;
    }
  public BufferedImage composeImageForSector(
      Sector sector,
      int imageWidth,
      int imageHeight,
      int levelNumber,
      String mimeType,
      boolean abortOnError,
      BufferedImage image) {
    if (sector == null) {
      String message = Logging.getMessage("nullValue.SectorIsNull");
      Logging.logger().severe(message);
      throw new IllegalStateException(message);
    }

    if (levelNumber < 0) {
      levelNumber = this.levels.getLastLevel().getLevelNumber();
    } else if (levelNumber > this.levels.getLastLevel().getLevelNumber()) {
      Logging.logger()
          .warning(
              Logging.getMessage(
                  "generic.LevelRequestedGreaterThanMaxLevel",
                  levelNumber,
                  this.levels.getLastLevel().getLevelNumber()));
      levelNumber = this.levels.getLastLevel().getLevelNumber();
    }

    MercatorTextureTile[][] tiles = this.getTilesInSector(sector, levelNumber);

    if (tiles.length == 0 || tiles[0].length == 0) {
      Logging.logger().severe(Logging.getMessage("layers.TiledImageLayer.NoImagesAvailable"));
      return null;
    }

    if (image == null)
      image = new BufferedImage(imageWidth, imageHeight, BufferedImage.TYPE_INT_RGB);

    Graphics2D g = image.createGraphics();

    for (MercatorTextureTile[] row : tiles) {
      for (MercatorTextureTile tile : row) {
        if (tile == null) continue;

        BufferedImage tileImage;
        try {
          tileImage = this.getImage(tile, mimeType);

          double sh =
              ((double) imageHeight / (double) tileImage.getHeight())
                  * (tile.getSector().getDeltaLat().divide(sector.getDeltaLat()));
          double sw =
              ((double) imageWidth / (double) tileImage.getWidth())
                  * (tile.getSector().getDeltaLon().divide(sector.getDeltaLon()));

          double dh =
              imageHeight
                  * (-tile.getSector().getMaxLatitude().subtract(sector.getMaxLatitude()).degrees
                      / sector.getDeltaLat().degrees);
          double dw =
              imageWidth
                  * (tile.getSector().getMinLongitude().subtract(sector.getMinLongitude()).degrees
                      / sector.getDeltaLon().degrees);

          AffineTransform txf = g.getTransform();
          g.translate(dw, dh);
          g.scale(sw, sh);
          g.drawImage(tileImage, 0, 0, null);
          g.setTransform(txf);
        } catch (Exception e) {
          if (abortOnError) throw new RuntimeException(e);

          String message =
              Logging.getMessage("generic.ExceptionWhileRequestingImage", tile.getPath());
          Logging.logger().log(java.util.logging.Level.WARNING, message, e);
        }
      }
    }

    return image;
  }
  public static DataRaster wrapAsGeoreferencedRaster(BufferedImage image, AVList params) {
    if (null == image) {
      String message = Logging.getMessage("nullValue.ImageIsNull");
      Logging.logger().severe(message);
      throw new IllegalArgumentException(message);
    }

    if (null == params) {
      String msg = Logging.getMessage("nullValue.AVListIsNull");
      Logging.logger().finest(msg);
      throw new IllegalArgumentException(msg);
    }

    if (params.hasKey(AVKey.WIDTH)) {
      int width = (Integer) params.getValue(AVKey.WIDTH);
      if (width != image.getWidth()) {
        String msg =
            Logging.getMessage("generic.InvalidWidth", "" + width + "!=" + image.getWidth());
        Logging.logger().finest(msg);
        throw new IllegalArgumentException(msg);
      }
    }

    if (params.hasKey(AVKey.HEIGHT)) {
      int height = (Integer) params.getValue(AVKey.HEIGHT);
      if (height != image.getHeight()) {
        String msg =
            Logging.getMessage("generic.InvalidHeight", "" + height + "!=" + image.getHeight());
        Logging.logger().finest(msg);
        throw new IllegalArgumentException(msg);
      }
    }

    if (!params.hasKey(AVKey.SECTOR)) {
      String msg = Logging.getMessage("generic.MissingRequiredParameter", AVKey.SECTOR);
      Logging.logger().finest(msg);
      throw new IllegalArgumentException(msg);
    }

    Sector sector = (Sector) params.getValue(AVKey.SECTOR);
    if (null == sector) {
      String msg = Logging.getMessage("nullValue.SectorIsNull");
      Logging.logger().severe(msg);
      throw new IllegalArgumentException(msg);
    }

    if (!params.hasKey(AVKey.COORDINATE_SYSTEM)) {
      // assume Geodetic Coordinate System
      params.setValue(AVKey.COORDINATE_SYSTEM, AVKey.COORDINATE_SYSTEM_GEOGRAPHIC);
    }

    String cs = params.getStringValue(AVKey.COORDINATE_SYSTEM);
    if (!params.hasKey(AVKey.PROJECTION_EPSG_CODE)) {
      if (AVKey.COORDINATE_SYSTEM_GEOGRAPHIC.equals(cs)) {
        // assume WGS84
        params.setValue(AVKey.PROJECTION_EPSG_CODE, GeoTiff.GCS.WGS_84);
      } else {
        String msg =
            Logging.getMessage("generic.MissingRequiredParameter", AVKey.PROJECTION_EPSG_CODE);
        Logging.logger().finest(msg);
        throw new IllegalArgumentException(msg);
      }
    }

    // if PIXEL_WIDTH is specified, we are not overriding it because UTM images
    // will have different pixel size
    if (!params.hasKey(AVKey.PIXEL_WIDTH)) {
      if (AVKey.COORDINATE_SYSTEM_GEOGRAPHIC.equals(cs)) {
        double pixelWidth = sector.getDeltaLonDegrees() / (double) image.getWidth();
        params.setValue(AVKey.PIXEL_WIDTH, pixelWidth);
      } else {
        String msg = Logging.getMessage("generic.MissingRequiredParameter", AVKey.PIXEL_WIDTH);
        Logging.logger().finest(msg);
        throw new IllegalArgumentException(msg);
      }
    }

    // if PIXEL_HEIGHT is specified, we are not overriding it
    // because UTM images will have different pixel size
    if (!params.hasKey(AVKey.PIXEL_HEIGHT)) {
      if (AVKey.COORDINATE_SYSTEM_GEOGRAPHIC.equals(cs)) {
        double pixelHeight = sector.getDeltaLatDegrees() / (double) image.getHeight();
        params.setValue(AVKey.PIXEL_HEIGHT, pixelHeight);
      } else {
        String msg = Logging.getMessage("generic.MissingRequiredParameter", AVKey.PIXEL_HEIGHT);
        Logging.logger().finest(msg);
        throw new IllegalArgumentException(msg);
      }
    }

    if (!params.hasKey(AVKey.PIXEL_FORMAT)) {
      params.setValue(AVKey.PIXEL_FORMAT, AVKey.IMAGE);
    } else if (!AVKey.IMAGE.equals(params.getStringValue(AVKey.PIXEL_FORMAT))) {
      String msg =
          Logging.getMessage(
              "generic.UnknownValueForKey",
              params.getStringValue(AVKey.PIXEL_FORMAT),
              AVKey.PIXEL_FORMAT);
      Logging.logger().severe(msg);
      throw new IllegalArgumentException(msg);
    }

    if (!params.hasKey(AVKey.ORIGIN) && AVKey.COORDINATE_SYSTEM_GEOGRAPHIC.equals(cs)) {
      // set UpperLeft corner as the origin, if not specified
      LatLon origin = new LatLon(sector.getMaxLatitude(), sector.getMinLongitude());
      params.setValue(AVKey.ORIGIN, origin);
    }

    if (!params.hasKey(AVKey.DATE_TIME)) {
      // add NUL (\0) termination as required by TIFF v6 spec (20 bytes length)
      String timestamp = String.format("%1$tY:%1$tm:%1$td %tT\0", Calendar.getInstance());
      params.setValue(AVKey.DATE_TIME, timestamp);
    }

    if (!params.hasKey(AVKey.VERSION)) {
      params.setValue(AVKey.VERSION, Version.getVersion());
    }

    boolean hasAlpha = (null != image.getColorModel() && image.getColorModel().hasAlpha());
    params.setValue(AVKey.RASTER_HAS_ALPHA, hasAlpha);

    return new BufferedImageRaster(sector, image, params);
  }
  protected void doDrawOnTo(BufferedImageRaster canvas) {
    Sector sector = this.getSector();
    if (null == sector) {
      String message = Logging.getMessage("nullValue.SectorIsNull");
      Logging.logger().severe(message);
      throw new IllegalArgumentException(message);
    }

    if (!sector.intersects(canvas.getSector())) {
      return;
    }

    java.awt.Graphics2D g2d = null;
    java.awt.Shape prevClip = null;
    java.awt.Composite prevComposite = null;
    java.lang.Object prevInterpolation = null, prevAntialiasing = null;

    try {
      int canvasWidth = canvas.getWidth();
      int canvasHeight = canvas.getHeight();

      // Apply the transform that correctly maps the image onto the canvas.
      java.awt.geom.AffineTransform transform =
          this.computeSourceToDestTransform(
              this.getWidth(),
              this.getHeight(),
              this.getSector(),
              canvasWidth,
              canvasHeight,
              canvas.getSector());

      AffineTransformOp op = new AffineTransformOp(transform, AffineTransformOp.TYPE_BILINEAR);
      Rectangle2D rect = op.getBounds2D(this.getBufferedImage());

      int clipWidth =
          (int) Math.ceil((rect.getMaxX() >= canvasWidth) ? canvasWidth : rect.getMaxX());
      int clipHeight =
          (int) Math.ceil((rect.getMaxY() >= canvasHeight) ? canvasHeight : rect.getMaxY());

      if (clipWidth <= 0 || clipHeight <= 0) {
        return;
      }

      g2d = canvas.getGraphics();

      prevClip = g2d.getClip();
      prevComposite = g2d.getComposite();
      prevInterpolation = g2d.getRenderingHint(RenderingHints.KEY_INTERPOLATION);
      prevAntialiasing = g2d.getRenderingHint(RenderingHints.KEY_ANTIALIASING);

      // Set the alpha composite for appropriate alpha blending.
      g2d.setComposite(java.awt.AlphaComposite.SrcOver);
      g2d.setRenderingHint(
          RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
      g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);

      g2d.drawImage(this.getBufferedImage(), transform, null);
    }
    //        catch (java.awt.image.ImagingOpException ioe)
    //        {
    //            // If we catch a ImagingOpException, then the transformed image has a width or
    // height of 0.
    //            // This indicates that there is no intersection between the source image and the
    // canvas,
    //            // or the intersection is smaller than one pixel.
    //        }
    //        catch (java.awt.image.RasterFormatException rfe)
    //        {
    //            // If we catch a RasterFormatException, then the transformed image has a width or
    // height of 0.
    //            // This indicates that there is no intersection between the source image and the
    // canvas,
    //            // or the intersection is smaller than one pixel.
    //        }
    catch (Throwable t) {
      String reason = WWUtil.extractExceptionReason(t);
      Logging.logger().log(java.util.logging.Level.SEVERE, reason, t);
    } finally {
      // Restore the previous clip, composite, and transform.
      try {
        if (null != g2d) {
          if (null != prevClip) g2d.setClip(prevClip);

          if (null != prevComposite) g2d.setComposite(prevComposite);

          if (null != prevInterpolation)
            g2d.setRenderingHint(RenderingHints.KEY_INTERPOLATION, prevInterpolation);

          if (null != prevAntialiasing)
            g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, prevAntialiasing);
        }
      } catch (Throwable t) {
        Logging.logger().log(java.util.logging.Level.FINEST, WWUtil.extractExceptionReason(t), t);
      }
    }
  }
  protected Sector resizeShape(Movable dragObject, int side) {
    if (dragObject instanceof SurfaceSector) {
      SurfaceSector quad = (SurfaceSector) dragObject;
      Sector s = quad.getSector(); // TODO: go over all sectors
      Position p = this.getWwd().getCurrentPosition();

      if (p == null || this.getPreviousPosition() == null) {
        return null;
      }

      Angle dLat = p.getLatitude().subtract(this.getPreviousPosition().getLatitude());
      Angle dLon = p.getLongitude().subtract(this.getPreviousPosition().getLongitude());

      Angle newMinLat = s.getMinLatitude();
      Angle newMinLon = s.getMinLongitude();
      Angle newMaxLat = s.getMaxLatitude();
      Angle newMaxLon = s.getMaxLongitude();

      if (side == NORTH) {
        newMaxLat = s.getMaxLatitude().add(dLat);
      } else if (side == SOUTH) {
        newMinLat = s.getMinLatitude().add(dLat);
      } else if (side == EAST) {
        newMaxLon = s.getMaxLongitude().add(dLon);
      } else if (side == WEST) {
        newMinLon = s.getMinLongitude().add(dLon);
      } else if (side == NORTHWEST) {
        newMaxLat = s.getMaxLatitude().add(dLat);
        newMinLon = s.getMinLongitude().add(dLon);
      } else if (side == NORTHEAST) {
        newMaxLat = s.getMaxLatitude().add(dLat);
        newMaxLon = s.getMaxLongitude().add(dLon);
      } else if (side == SOUTHWEST) {
        newMinLat = s.getMinLatitude().add(dLat);
        newMinLon = s.getMinLongitude().add(dLon);
      } else if (side == SOUTHEAST) {
        newMinLat = s.getMinLatitude().add(dLat);
        newMaxLon = s.getMaxLongitude().add(dLon);
      }

      return new Sector(newMinLat, newMaxLat, newMinLon, newMaxLon);
    }

    return null;
  }