Вложенные квадраты

unit Unit1;
 
interface
 
uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  ExtCtrls, StdCtrls;
 
type
  TForm1 = class(TForm)
    Timer1: TTimer;
    Image1: TImage;
    procedure FormCreate(Sender: TObject);
    procedure Timer1Timer(Sender: TObject);
  private
    { Private declarations }
    Procedure RotateRect;
  public
    { Public declarations }
  end;
 
var
  Form1: TForm1;
 
implementation
 
{$R *.DFM}
 
procedure TForm1.FormCreate(Sender: TObject);
begin
 DoubleBuffered := true;
end;
 
procedure TForm1.RotateRect;
Const N = 55;
      DT = 20;
      SD = 0;
 
Const IC : Integer = 250;
      ID : ShortInt = -1;
Var Col        : TColor;
    RC, GC, BC : Integer; // Составляющие цвета
    Pnt        : Array [1..4] of TPoint;
    mx, my     : Integer;
    d          : ShortInt;
    i          : Integer;
begin
  With Image1 do begin
    Pnt[1].x := SD;
    Pnt[1].y := SD;
    Pnt[2].x := Width - SD;
    Pnt[2].y := SD;
    Pnt[3].x := Width - SD;
    Pnt[3].y := Height - SD;
    Pnt[4].x := SD;
    Pnt[4].y := Height - SD;
    GC :=0; RC := 0; BC := IC;
    d := id;
    Col := RGB( BC, GC, BC);
    Canvas.Pen.Color   := Col;
    Canvas.Brush.Color := Col;
    Canvas.Polygon( Pnt);
    For i:=1 to N do begin
      mx := Pnt[1].x;
      my := Pnt[1].y;
      Pnt[1].x := Pnt[1].x + (Pnt[2].x - Pnt[1].x) div DT;
      Pnt[1].y := Pnt[1].y + (Pnt[2].y - Pnt[1].y) div DT;
      Pnt[2].x := Pnt[2].x + (Pnt[3].x - Pnt[2].x) div DT;
      Pnt[2].y := Pnt[2].y + (Pnt[3].y - Pnt[2].y) div DT;
      Pnt[3].x := Pnt[3].x + (Pnt[4].x - Pnt[3].x) div DT;
      Pnt[3].y := Pnt[3].y + (Pnt[4].y - Pnt[3].y) div DT;
      Pnt[4].x := Pnt[4].x + (mx - Pnt[4].x) div DT;
      Pnt[4].y := Pnt[4].y + (my - Pnt[4].y) div DT;
      if BC >= 255 then d := -1;
      if BC <= 0   then d := 1;
      BC := BC + d * 5;
      Col := RGB( BC, GC, BC);
      Canvas.Pen.Color   := Col;
      Canvas.Brush.Color := Col;
      Canvas.Polygon( Pnt);
    end;
  if IC >= 255 then begin Id := 1; end;
  if IC <= 0 then begin Id := -1;  end;
  IC := IC - id * 5;
  end;
end;
 
procedure TForm1.Timer1Timer(Sender: TObject);
begin
  RotateRect;
end;
 
end.