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procedure TForm1.Timer1Timer(Sender: TObject);
begin

  if image1.top < form1.width then
  begin
    form1.color := clWhite;
    image1.left := image1.top + 90
  end
  else
  begin
    form1.color := clBlack;
    image2.left := image2.top + 90

end
end;

end.					

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procedure TForm1.Timer1Timer(Sender: TObject);
const
 dx = 90;
 dy = 90;
begin
 if Shape1.Top < ClientHeight-Shape1.Height-dy then
  Shape1.Top := Shape1.Top + dy else
  if Shape2.Left < ClientWidth-Shape2.Width-dx then
   Shape2.Left := Shape2.Left + dx
end;