rob1.rtf

unit rob1;

interface

uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

  Dialogs, StdCtrls;

type

  TForm1 = class(TForm)

    Button1: TButton;

    ScrollBar1: TScrollBar;

    ScrollBar2: TScrollBar;

    procedure Button1Click(Sender: TObject);

    procedure ScrollBar1Change(Sender: TObject);

    procedure ScrollBar2Change(Sender: TObject);

  private

    { Private declarations }

  public

    { Public declarations }

  end;

var

  Form1: TForm1;

  x,y,yy,x0,y0,x1,y1 : longint ;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);

begin

x0:= 450;

y0:= 250;

x1:= 550;

y1:= 250;

scrollbar1.Position:=0;

scrollbar2.Position:=0;

//form1.Color:=rgb(255,255,0);

//form1.Color:=rgb(255,255,255);

canvas.Pen.Color:=clred ;

canvas.MoveTo(350,350);

canvas.LineTo(350,250);

canvas.LineTo(x0,y0);

canvas.LineTo(x1,y1);

end;

procedure TForm1.ScrollBar1Change(Sender: TObject);

begin

canvas.Pen.Color:=clwhite ;

canvas.MoveTo(350,350);

canvas.LineTo(350,250);

canvas.LineTo(x0,y0);

canvas.LineTo(x1,y1);

y:= (scrollbar1.Position);

y0:=250-y;

y1:=y0-yy;

canvas.Pen.Color:=clred ;

canvas.MoveTo(350,350);

canvas.LineTo(350,250);

canvas.LineTo(x0,y0);

canvas.LineTo(x1,y1);

end;

procedure TForm1.ScrollBar2Change(Sender: TObject);

begin

canvas.Pen.Color:=clwhite ;

canvas.MoveTo(x0,y0);

//canvas.LineTo(350,250);

canvas.LineTo(x1,y1);

yy:= (scrollbar2.Position);

y1:=y0-yy;

canvas.Pen.Color:=clred ;

canvas.MoveTo(x0,y0);

//canvas.LineTo(350,250);

canvas.LineTo(x1,y1);

end;

end.