How to get a line in a RichEdit just like in the Delphi editor?

This code creates a line in a TRichEdit similar to the line in the Delphi editor, to indicate the fact that you have reached a certain amount of characters on that line.

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Procedure TForm1.RichEdit1Change(Sender : TObject);

Var
  aCanvas             : Tcanvas;
  X1,X2,Y             : Integer;

Begin
aCanvas := TCanvas.Create;
Y := RichEdit1.Height;
Try
   aCanvas.Handle := GetDC(RichEdit1.Handle);
   With aCanvas do
      Begin
      Font := RichEdit1.Font;
      X1 := TextWidth('W');
      X2 := TextWidth('i');
      Pen.color := clSilver;
      If X1 = X2 then // Simple way of testing for fixed font type
         Begin
         MoveTo(79 * X1,0); // Draw line after 80 characters
         LineTo(79 * X1,Y);
         End;
      End;
   Finally
      ReleaseDC(RichEdit1.Handle,aCanvas.Handle);
      aCanvas.Free;
   End;
End;
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