queen.pas

用于开发税务票据管理的软件

unit Queen;

interface

uses
  SysUtils, WinTypes, Classes, Graphics, Piece;

type
//  TQueenPtr = ^TQueen;
  TQueen = class(TPiece)
  private
    { Private declarations }
  protected
    { Protected declarations }
    procedure ChangeColour(NewVal: TColour); override;
    function GetStartingLocation(NumberOfItems: Byte): TPoint; override;
  public
    { Public declarations }
    constructor Create(AOwner: TComponent); override;

    function ValidMove(Where: TPoint): Boolean; override;
  published
    { Published declarations }

  end;

implementation

constructor TQueen.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  if FileExists(FStartDir + 'Pictures\QueenW.bmp') then
  begin
    Picture.LoadFromFile(FStartDir + 'Pictures\QueenW.bmp');
    Picture.Graphic.Transparent := True;
  end;

  Hint := 'Queen';
  FPrefix := 'Q';
  FValue := 9;
end;

function TQueen.GetStartingLocation(NumberOfItems: byte): TPoint;
begin
  Result.X := 4;
  if Colour = cWhite then
    Result.Y := 1
  else
    Result.Y := 8;
end;

function TQueen.ValidMove(Where: TPoint): Boolean;
var
  DiffX: Integer;
  DiffY: Integer;
begin
  Result := False;
  if (Where.X in [1..8]) and (Where.Y in [1..8]) then
    { Check for same square move }
    if ((Where.X - FX) or (Where.Y - FY)) <> 0 then
    begin
      { Check rook's move for queen }
      if (Where.X = FX) xor (Where.Y = FY) then
        Result := True
      else
      begin
        { Not a rook move, check for bishop move }
        DiffX := abs(Where.X - FX);
        DiffY := abs(Where.Y - FY);

        Result := (DiffX = DiffY);
      end;
    end;
end;

procedure TQueen.ChangeColour(NewVal: TColour);
var
  FileName: String;
begin
  inherited ChangeColour(NewVal);
  FileName := FStartDir + 'Pictures\Queen';
  if FPlayer = cBlack then
    FileName := FileName + 'B.bmp'
  else
    FileName := FileName + 'W.bmp';
  if FileExists(FileName) then
  begin
    Picture.LoadFromFile(FileName);
    Picture.Graphic.Transparent := True;
  end;
end;

end.