BNGCoordSystem.java

static public CoordSystem MakeBNGCoordSystem(Activity activity, boolean displayVersion)
{
  String projStr = "+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +units=m +no_defs";
  Proj4CoordSystem coordSys = new Proj4CoordSystem(projStr);

  // Set the bounding box for validity.  It assumes it can go everywhere by default
  Mbr bbox = new Mbr();
  bbox.addPoint(new Point2d(1393.0196,13494.9764));
  bbox.addPoint(new Point2d(671196.3657,1230275.0454));

  // Now expand it out so we can see the whole of the UK
  if (displayVersion)
  {
    // Make the bounds a little bigger to give the user room
    double spanX = bbox.ur.getX() - bbox.ll.getX();
    double spanY = bbox.ur.getY() - bbox.ll.getY();
    double extra = 1.5;
    bbox.addPoint(new Point2d(-extra*spanX,-extra*spanY));
    bbox.addPoint(new Point2d(extra*spanX,extra*spanY));
  }

  coordSys.setBounds(bbox);

  return coordSys;
}