TGIS_ShortestPath.Find method

DK11 for Delphi | GisShortestPath.TGIS_ShortestPath.Find | Constructors | Methods | Properties | Events

Find path between two existing nodes.

Available also on: .NET | Java | ActiveX | Python.

// Delphi
public
  function Find(
    const _from : TGIS_Point;
    const _to : TGIS_Point
  ) : Boolean;

// C++ Builder
public:
  bool Find(
    TGIS_Point* const _from,
    TGIS_Point* const _to
  );

var
  GIS: TGIS_ViewerWnd;
  layerRoute : TGIS_LayerVector ;
  rtrObj : TGIS_ShortestPath ;
  Highways, SmallRoads, res : Integer;
  AddrFrom, AddrTo, ang, clue : String;
begin
 
  // modify cost values for roads type
  rtrObj.CostModifiers[0] := 1 - 1/11 * Highways;
  rtrObj.CostModifiers[1] := 1 - 1/11 * SmallRoads;
 
  // let's find a starting position
  res := geoObj.Parse( AddrFrom) ;
  if res > 0 then AddrFrom := geoObj.Query[0]
             else AddrFrom :=  AddrFrom + ' ???' ;
 
  if res <= 0 then exit ;
  pt_a := geoObj.Point[0]  ;
 
  // let's find an ending position
  res := geoObj.Parse(AddrTo) ;
  if res > 0 then AddrTo := geoObj.Query[0]
             else AddrTo:= AddrTo + ' ???' ;
 
  if res <= 0 then exit ;
  pt_b := geoObj.Point[0]  ;
 
  // update the layer data and set start, stop position
  rtrObj.UpdateTheData ;
  rtrObj.Find( layerRoute.Unproject( pt_a ),
               layerRoute.Unproject( pt_b ),
             )
  for i:=0 to rtrObj.ItemsCount -1 do begin
    case rtrObj.Items[i].Compass of
      0 : ang := 'FWD  ' ;
      1 : ang := 'RIGHT' ;
      2 : ang := 'RIGHT' ;
      3 : ang := 'RIGHT' ;
      4 : ang := 'BACK ' ;
     -1 : ang := 'LEFT ' ;
     -2 : ang := 'LEFT ' ;
     -3 : ang := 'LEFT ' ;
     -4 : ang := 'BACK ' ;
    end ;
    clue:=Format( '%s, %s', [ clue, ang ] )
 
    dosomething();
  end;
 
end;

• Geocoding sample