unit nkBox;
{
   Class for a box in xy-plane.
   Box coordinates goes like in real xy-plane.

   Author:  Vesa Lappalainen
   Date:    15.2.1998
   Changes:

}

interface
  uses Windows,Classes,nkPoint, nkscale;

type  
  TDBox = class;
  TInformDBox = procedure (const p:TDBox) of object;

  TDBox = class(TPersistent)
  private
    Fp  : TDPoint;
    Fdp : TDPoint;
    Ftp : TDPoint;
    FOrigo : TDPoint;
    FInform : TInformDBox;
    FDoInform : boolean;
  protected

  public
    constructor Create; virtual;
    constructor Create5(ix,iy,idx,idy:double;IInform:TInformDBox); virtual;
    destructor Destroy; override;
    procedure PChange(const p:TDPoint); virtual;
    procedure FromWin(ix,iy,idx,idy:integer; const scale:TScale); virtual;
    procedure ToWin(var ip,idp : TPoint; const scale:TScale); virtual;
    procedure ToWinDXY(var ip,idp : TPoint; const scale:TScale; idx,idy:integer); virtual;
    procedure SetDoInform(value:boolean); virtual;
    property DoInform : boolean read FDoInform write SetDoInform;
  published
    property p : TDPoint read Fp write Fp;
    property dp : TDPoint read Fdp write Fdp;
    property Origo : TDPoint read FOrigo write FOrigo;
  end;

implementation


//-----------------------------------------------------------------------------
constructor TDBox.Create; //  override;
begin
  Create5(0,0,5,5,nil);
end;


//-----------------------------------------------------------------------------
constructor TDBox.Create5(ix,iy,idx,idy:double;IInform:TInformDBox); //  virtual;
begin
  inherited Create;
  Fp      := TDPoint.Create3(ix,iy,PChange);
  Fdp     := TDPoint.Create3(idx,idy,PChange);
  FOrigo  := TDPoint.Create3(0,0,PChange);
  Ftp     := TDPoint.Create3(0,0,nil);
  Finform := IInform;
  FDoInform := true;
end;


//-----------------------------------------------------------------------------
procedure TDBox.PChange(const p:TDPoint); //  virtual;
begin
  if Assigned(FInform) and FDoInform then FInform(self);
end;


//-----------------------------------------------------------------------------
destructor TDBox.Destroy; //  override;
begin
  Ftp.Free;
  FOrigo.Free;
  Fdp.Free;
  Fp.Free;
  inherited;
end;


//-----------------------------------------------------------------------------
procedure TDBox.FromWin(ix,iy,idx,idy:integer; const scale:TScale); //  virtual;
var ip,idp : TPoint; oldInfo : boolean;
begin
  if ( Scale = nil ) then begin
    p.SetXYnu(ix+Origo.x,iy+Origo.y);
    dp.SetXY(idx,idy);
    exit;
  end;
  ip.x := ix ; ip.y := iy; idp.x := idx; idp.y := idy;
  if ( Scale.Fac.x < 0 ) then ip.x := ip.x + idx;
  if ( Scale.Fac.y > 0 ) then ip.y := ip.y + idy;

  oldInfo := DoInform; DoInform := false;

  Scale.UpScaleP(ip,p); p.AddV(Origo);
  Scale.UpScaleDP(idp,dp);

  DoInform := oldInfo;
  PChange(nil);
end;


//-----------------------------------------------------------------------------
procedure TDBox.ToWinDXY(var ip,idp : TPoint; const scale:TScale; idx,idy:integer); //  virtual;
begin
  if ( Scale = nil ) then begin
    ip.x  := trunc(p.x-Origo.x);   ip.y  := trunc(p.y-Origo.y);
    idp.x := trunc(dp.x);          idp.y := trunc(dp.y);
    exit;
  end;

  Ftp.Assign(p);  Ftp.SubV(Origo);
  ip  := Scale.DownScaleP(Ftp);
  idp := Scale.DownScaleDP(dp);
  if ( Scale.Fac.x < 0 ) then begin
     idp.x := abs(idp.x);
     ip.x := ip.x - idp.x - idx;
   end
  else ip.x := ip.x + idx;
  if ( Scale.Fac.y > 0 ) then ip.y := ip.y - idp.y - idy
                         else begin
                           idp.y := abs(idp.y);
                           ip.y := ip.y + idy;
                         end;  
end;


//-----------------------------------------------------------------------------
procedure TDBox.ToWin(var ip,idp : TPoint; const scale:TScale); //  virtual;
begin
  ToWinDXY(ip,idp,scale,0,0);
end;


//-----------------------------------------------------------------------------
procedure TDBox.SetDoInform(value:boolean); //  virtual;
begin
  FDoInform := value;
  PChange(nil);
end;


end.