ui/src/main/java/ucar/nc2/ui/geoloc/Navigation.java
public ProjectionRect getMapArea(ProjectionRect rect) {
    if (rect == null)
      rect = new ProjectionRect();

    double width = pwidth/pix_per_world;
    double height = pheight/pix_per_world;

        // center point
    double wx0 = (pwidth/2-pix_x0)/pix_per_world;
    double wy0 = (pix_y0-pheight/2)/pix_per_world;

    rect.setRect(wx0-width/2, wy0-height/2,             // minx, miny
             width, height);                            // width, height

    return rect;
  }
public ProjectionRect getMapArea(ProjectionRect rect) {
    if (rect == null)
      rect = new ProjectionRect();

    double width = pwidth/pix_per_world;
    double height = pheight/pix_per_world;

        // center point
    double wx0 = (pwidth/2-pix_x0)/pix_per_world;
    double wy0 = (pix_y0-pheight/2)/pix_per_world;

    rect.setRect(wx0-width/2, wy0-height/2,             // minx, miny
             width, height);                            // width, height

    return rect;
  }
Get current MapArea .
@param rect : place results here, or null to create new Object