/**
   * Compute the bounds of the text, if necessary.
   *
   * @param dc the current DrawContext.
   */
  protected void computeBoundsIfNeeded(DrawContext dc) {
    // Do not compute bounds if they are available. Computing text bounds is expensive, so only do
    // this
    // calculation if necessary.
    if (this.bounds != null) return;

    TextRenderer textRenderer =
        OGLTextRenderer.getOrCreateTextRenderer(dc.getTextRendererCache(), this.getFont());

    int width = 0;
    int maxLineHeight = 0;
    this.lineBounds = new Rectangle2D[this.lines.length];

    for (int i = 0; i < this.lines.length; i++) {
      Rectangle2D lineBounds = textRenderer.getBounds(lines[i]);
      width = (int) Math.max(lineBounds.getWidth(), width);

      double thisLineHeight = Math.abs(lineBounds.getY());
      maxLineHeight = (int) Math.max(thisLineHeight, maxLineHeight);

      this.lineBounds[i] = lineBounds;
    }
    this.lineHeight = maxLineHeight;

    // Compute final height using maxLineHeight and number of lines
    this.bounds =
        new Rectangle(
            this.lines.length,
            maxLineHeight,
            width,
            this.lines.length * maxLineHeight + this.lines.length * this.lineSpacing);
  }
  /**
   * Select the visible grid elements
   *
   * @param dc the current <code>DrawContext</code>.
   */
  protected void selectRenderables(DrawContext dc) {
    if (dc == null) {
      String message = Logging.getMessage("nullValue.DrawContextIsNull");
      Logging.logger().severe(message);
      throw new IllegalArgumentException(message);
    }
    Sector vs = dc.getVisibleSector();
    OrbitView view = (OrbitView) dc.getView();
    // Compute labels offset from view center
    Position centerPos = view.getCenterPosition();
    Double pixelSizeDegrees =
        Angle.fromRadians(
                view.computePixelSizeAtDistance(view.getZoom())
                    / dc.getGlobe().getEquatorialRadius())
            .degrees;
    Double labelOffsetDegrees = pixelSizeDegrees * view.getViewport().getWidth() / 4;
    Position labelPos =
        Position.fromDegrees(
            centerPos.getLatitude().degrees - labelOffsetDegrees,
            centerPos.getLongitude().degrees - labelOffsetDegrees,
            0);
    Double labelLatDegrees = labelPos.getLatitude().normalizedLatitude().degrees;
    labelLatDegrees = Math.min(Math.max(labelLatDegrees, -76), 78);
    labelPos =
        new Position(
            Angle.fromDegrees(labelLatDegrees), labelPos.getLongitude().normalizedLongitude(), 0);

    if (vs != null) {
      for (GridElement ge : this.gridElements) {
        if (ge.isInView(dc)) {
          if (ge.renderable instanceof GeographicText) {
            GeographicText gt = (GeographicText) ge.renderable;
            if (labelPos.getLatitude().degrees < 72
                || "*32*34*36*".indexOf("*" + gt.getText() + "*") == -1) {
              // Adjust label position according to eye position
              Position pos = gt.getPosition();
              if (ge.type.equals(GridElement.TYPE_LATITUDE_LABEL))
                pos =
                    Position.fromDegrees(
                        pos.getLatitude().degrees,
                        labelPos.getLongitude().degrees,
                        pos.getElevation());
              else if (ge.type.equals(GridElement.TYPE_LONGITUDE_LABEL))
                pos =
                    Position.fromDegrees(
                        labelPos.getLatitude().degrees,
                        pos.getLongitude().degrees,
                        pos.getElevation());

              gt.setPosition(pos);
            }
          }

          this.graticuleSupport.addRenderable(ge.renderable, GRATICULE_UTM);
        }
      }
      // System.out.println("Total elements: " + count + " visible sector: " + vs);
    }
  }