nstrate the GetImage and PutImage commands }

const
  r  = 20;
  StartX = 100;
  StartY = 50;

var
  CurPort : ViewPortType;

procedure MoveSaucer(var X, Y : integer; Width, Height : integer);
var
  Step : integer;
begin
  Step := Random(2*r);
  if Odd(Step) then
    Step := -Step;
  X := X + Step;
  Step := Random(r);
  if Odd(Step) then
    Step := -Step;
  Y := Y + Step;

  { Make saucer bounce off viewport walls }
  with CurPort do
  begin
    if (x1 + X + Width - 1 > x2) then
      X := x2-x1 - Width + 1
    else
      if (X < 0) then
        X := 0;
    if (y1 + Y + Height - 1 > y2) then
      Y := y2-y1 - Height + 1
    else
      if (Y < 0) then
        Y := 0;
  end;
end; { MoveSaucer }

var
  Pausetime : word;
  Saucer    : pointer;
  X, Y      : integer;
  ulx, uly  : word;
  lrx, lry  : word;
  Size      : word;
  I         : word;
begin
  ClearDevice;
  FullPort;

  { PaintScreen }
  ClearDevice;
  MainWindow('GetImage / PutImage Demonstration');
  StatusLine('Esc aborts or press a key...');
  GetViewSettings(CurPort);

  { DrawSaucer }
  Ellipse(StartX, StartY, 0, 360, r, (r div 3)+2);
  Ellipse(St