anchor.diff:  
   procedure TMainForm.HandlePaint;
   begin
  -  Canvas.BeginDraw;
     inherited HandlePaint;
   
     if rbSpokes.Checked then
  
positive.code:     DrawLines
    else if rbSpiral.Checked then
      DrawSpiral;
  
    Canvas.EndDraw;
  end;
  
  procedure TMainForm.btnQuitClicked(Sender: TObject);
  
negative.code:   X1 := 300;
    Y1 := 100;
    Theta := 0;
  
    while Theta < 15 * 3.1415926535 do
    begin
      X2 := trunc(X1 + Cos(Theta) * Theta);
  