{
DEBTRACE("GetAltitudeForPoint p(" << thePoint.X() << ", " << thePoint.Y() << ")");
double aResAltitude = GetInvalidAltitude();
{
DEBTRACE("GetAltitudeForPoint p(" << thePoint.X() << ", " << thePoint.Y() << ")");
double aResAltitude = GetInvalidAltitude();