+
+
+// AltitudePoints anAltitudePoints = GetAltitudePoints();
+// if ( anAltitudePoints.IsEmpty() )
+// return aResAltitude;
+//
+// QPolygonF aBoundingRect;
+//
+// // Boundary plane
+// // [ 0 (top-left) ] [ 1 (top-right) ]
+// // thePoint
+// // [ 2 (bot-left) ] [ 3 (bot-right) ]
+// AltitudePoint aBounds[ 4 ] = { AltitudePoint( -DBL_MAX, -DBL_MAX, anInvalidAltitude ),
+// AltitudePoint( DBL_MAX, -DBL_MAX, anInvalidAltitude ),
+// AltitudePoint( -DBL_MAX, DBL_MAX, anInvalidAltitude ),
+// AltitudePoint( DBL_MAX, DBL_MAX, anInvalidAltitude ) };
+//
+// AltitudePoints::Iterator anIter( anAltitudePoints );
+// for ( ; anIter.More(); anIter.Next() )
+// {
+// const AltitudePoint& aPoint = anIter.Value();
+//
+// double aDeltaX = Abs( aPoint.X() ) - Abs( thePoint.X() );
+// double aDeltaY = Abs( aPoint.Y() ) - Abs( thePoint.Y() );
+//
+// if ( ValuesEquals( aDeltaX, 0.0 ) ) // Both left and right sides
+// {
+// if ( ValuesEquals( aDeltaY, 0.0 ) ) // Both top and bottom sides
+// {
+// aResAltitude = aPoint.Z();
+// return aResAltitude;
+// }
+// else if ( aDeltaY < 0 ) // top side
+// {
+// // top border
+// if ( ValuesMoreEquals( aPoint.X(), aBounds[ 0 ].X() ) && ValuesMoreEquals( aPoint.Y(), aBounds[ 0 ].Y() ) )
+// aBounds[ 0 ] = aPoint;
+// if ( ValuesLessEquals( aPoint.X(), aBounds[ 1 ].X() ) && ValuesMoreEquals( aPoint.Y(), aBounds[ 1 ].Y() ) )
+// aBounds[ 1 ] = aPoint;
+// }
+// else
+// {
+// // bottom border
+// if ( ValuesMoreEquals( aPoint.X(), aBounds[ 2 ].X() ) && ValuesLessEquals( aPoint.Y(), aBounds[ 2 ].Y() ) )
+// aBounds[ 2 ] = aPoint;
+// if ( ValuesLessEquals( aPoint.X(), aBounds[ 3 ].X() ) && ValuesLessEquals( aPoint.Y(), aBounds[ 3 ].Y() ) )
+// aBounds[ 3 ] = aPoint;
+// }
+// }
+// else if ( aDeltaX < 0 ) // left side
+// {
+// if ( ValuesEquals( aDeltaY, 0.0 ) )
+// {
+// // Left border
+// if ( ValuesMoreEquals( aPoint.X(), aBounds[ 0 ].X() ) && ValuesMoreEquals( aPoint.Y(), aBounds[ 0 ].Y() ) )
+// aBounds[ 0 ] = aPoint;
+// if ( ValuesMoreEquals( aPoint.X(), aBounds[ 2 ].X() ) && ValuesLessEquals( aPoint.Y(), aBounds[ 2 ].Y() ) )
+// aBounds[ 2 ] = aPoint;
+// }
+// else if ( aDeltaY < 0 )
+// {
+// // top left corner
+// if ( ValuesMoreEquals( aPoint.X(), aBounds[ 0 ].X() ) && ValuesMoreEquals( aPoint.Y(), aBounds[ 0 ].Y() ) )
+// aBounds[ 0 ] = aPoint;
+// }
+// else
+// {
+// // bottom left corner
+// if ( ValuesMoreEquals( aPoint.X(), aBounds[ 2 ].X() ) && ValuesLessEquals( aPoint.Y(), aBounds[ 2 ].Y() ) )
+// aBounds[ 2 ] = aPoint;
+// }
+// }
+// else // right side
+// {
+// if ( ValuesEquals( aDeltaY, 0.0 ) )
+// {
+// // Right border
+// if ( ValuesLessEquals( aPoint.X(), aBounds[ 1 ].X() ) && ValuesMoreEquals( aPoint.Y(), aBounds[ 1 ].Y() ) )
+// aBounds[ 1 ] = aPoint;
+// if ( ValuesLessEquals( aPoint.X(), aBounds[ 3 ].X() ) && ValuesLessEquals( aPoint.Y(), aBounds[ 3 ].Y() ) )
+// aBounds[ 3 ] = aPoint;
+// }
+// else if ( aDeltaY < 0 )
+// {
+// // top right corner
+// if ( ValuesLessEquals( aPoint.X(), aBounds[ 1 ].X() ) && ValuesMoreEquals( aPoint.Y(), aBounds[ 1 ].Y() ) )
+// aBounds[ 1 ] = aPoint;
+// }
+// else
+// {
+// // bottom right corner
+// if ( ValuesLessEquals( aPoint.X(), aBounds[ 3 ].X() ) && ValuesLessEquals( aPoint.Y(), aBounds[ 3 ].Y() ) )
+// aBounds[ 3 ] = aPoint;
+// }
+// }
+//
+// // Update bounding rectangle of our global grid
+// aBoundingRect << QPointF( aPoint.X(), aPoint.Y() );
+// }
+//
+// const double LIMIT = 1E300;
+// if( fabs( aBounds[ 0 ].X() ) > LIMIT || fabs( aBounds[ 0 ].Y() ) > LIMIT ||
+// fabs( aBounds[ 1 ].X() ) > LIMIT || fabs( aBounds[ 1 ].Y() ) > LIMIT ||
+// fabs( aBounds[ 2 ].X() ) > LIMIT || fabs( aBounds[ 2 ].Y() ) > LIMIT ||
+// fabs( aBounds[ 3 ].X() ) > LIMIT || fabs( aBounds[ 3 ].Y() ) > LIMIT )
+// return anInvalidAltitude;
+//
+//
+// // Check if requested point is inside of our bounding rectangle
+// if ( !aBoundingRect.boundingRect().contains( thePoint.X(), thePoint.Y() ) )
+// return aResAltitude;
+//
+// // Calculate result altitude for point
+// AltitudePoint aFirstPoint( aBounds[ 0 ] ), aSecPoint( aBounds[ 1 ] );
+//
+// // At first we merge top and bottom borders
+// if ( aBounds[ 0 ].Y() != aBounds[ 2 ].Y() || aBounds[ 0 ].X() != aBounds[ 2 ].X() )
+// interpolateAltitudeForPoints( thePoint, aBounds[ 0 ], aBounds[ 2 ], aFirstPoint, true );
+//
+// if ( aBounds[ 1 ].Y() != aBounds[ 3 ].Y() || aBounds[ 1 ].X() != aBounds[ 3 ].X() )
+// interpolateAltitudeForPoints( thePoint, aBounds[ 1 ], aBounds[ 3 ], aSecPoint, true );
+//
+// AltitudePoint aResPoint( aFirstPoint );
+//
+// // At last we merge left and right borders
+// if ( aFirstPoint.Y() != aSecPoint.Y() || aFirstPoint.X() != aSecPoint.X() )
+// interpolateAltitudeForPoints( thePoint, aFirstPoint, aSecPoint, aResPoint, false );
+//
+// aResAltitude = aResPoint.Z();
+//
+// return aResAltitude;