anchor.diff:      property TerrainType: TTerrainType read FTerrainType write SetTerrainType;
     end;
   
  -
  -
  -
   implementation
   
   uses
  
positive.code:                 UpdateTerrain(it2^.Data, tileRequiresValidation);
               end;
            end;
  
  
          end;
          SuitableTiles.Free;
       end
  
negative.code:     until not it.next ;
      FreeAndNil(it);
    end;
  
    //save old state
    FOldTileInfos.Clear;
  