anchor.diff:  *)
   
   Procedure TRichTextView.DoVerticalScroll( NewY: longint );
  -
  -var
  -  ScrollDistance: longint;
  -begin
  -  FYScroll := NewY;
  +//var
  +//  ScrollDistance: longint;
  +begin
  +  FYScroll := 0 - NewY;
   
     if not Visible then
     begin
  
positive.code: 
    // Calculate available height.
    // Note: this depends on whether a h scroll bar is needed.
  
    AvailableHeight := Height;
    //if FBorderStyle <> bsNone then
    //  dec( AvailableHeight, 4 );
    if FNeedHScroll then
      dec( AvailableHeight, FScrollBarWidth );
  
    // Vertical scroll setup
  
    if FLayout.Height > AvailableHeight then
      FNeedVScroll := true;
  
    FVScrollBar.SliderSize := AvailableHeight;
    FVScrollBar.Min := 0;
  
    if FNeedVScroll then
    begin
      FVScrollBar.Max := FLayout.Height - 1;
    end
    else
    begin
      FVScrollBar.Position := 0;
      FVScrollBar.Max := 0;
    end;
  
    FHScrollBar.ScrollStep := 15; // pixels
    FHScrollBar.PageSize := AvailableWidth div 2;
    FVScrollBar.ScrollStep := 1; // not used (line up/down calculated explicitly)
    FVScrollBar.PageSize := GetTextAreaHeight div 2;
  
    // Physical horizontal scroll setup
    FHScrollbar.Visible := FNeedHScroll;
    FHScrollbar.Left := 0;
    FHScrollbar.Top := Height - FScrollBarWidth;
    FHScrollbar.Width := Width - FScrollBarWidth;
    FHScrollbar.Height := FScrollbarWidth;
  
    // Physical vertical scroll setup
    FVScrollbar.Visible := True;
    FVScrollbar.Enabled := FNeedVScroll;
    FVScrollbar.Left := Width - FScrollbarWidth;
    FVScrollbar.Top := 0;
    FVScrollbar.Width := FScrollbarWidth;
  
    if FNeedHScroll then
    begin
      FVScrollbar.Height := Height - FScrollbarWidth
    end
    else
    begin
      FVScrollbar.Height := Height;
    end;
  
    // Initialise scroll
    FYScroll := FVScrollBar.Position;
  
negative.code:     exit;
    end;
  
  //  ScrollDistance := FYScroll - FLastYScroll;
  
    { TODO -ograeme -cscrolling : Implement vertical scrolling here }
    //ScrollControlRect( Self,
  