unit Unit1;

{$mode objfpc}{$H+}

interface

uses

  Classes, SysUtils, FileUtil, Forms, Controls, Graphics, Dialogs, ExtCtrls;

type

  { TForm1 }

  TForm1 = class(TForm)

    Timer1: TTimer;

    procedure FormPaint(Sender: TObject);

    procedure Timer1Timer(Sender: TObject);

  private

    { private declarations }

  public

    { public declarations }

  end;

var

  Form1: TForm1;

  offset: integer = 0;

implementation

{$R *.lfm}

{ TForm1 }

procedure TForm1.FormPaint(Sender: TObject);

var

  x, y, realX, realY: integer;

  c: TColor;

begin

  c := clBlack;

  for x := 0 to 250-1 do begin

    for y := 0 to 100-1 do begin

      if (x mod 50 < 25) = (y mod 30 < 15) then c := clWhite else c := clNavy;

      //realX := 30 + x + y;

      //realY := 30 + 200 - y;

      //realX := 30 + 2*x + 2*y;

      //realY := 30 + 200 - 2*y;

      realX := 30 + 2*x + 2*y;

      realY := 30 + 200 - 2*y - round(10 * cos((x - offset)/10) * cos(y/10));

      Canvas.Pixels[realX, realY] := c;

    end;

  end;

end;

procedure TForm1.Timer1Timer(Sender: TObject);

begin

  offset := offset + 1;

  Refresh;

end;

end.