protected virtual void TrackBarDrawVerticalTrack (Graphics dc, Rectangle thumb_area, Point channel_startpoint, Rectangle clippingArea)
{
dc.FillRectangle (SystemBrushes.ControlDark, channel_startpoint.X, channel_startpoint.Y,
1, thumb_area.Height);
dc.FillRectangle (SystemBrushes.ControlDarkDark, channel_startpoint.X + 1, channel_startpoint.Y,
1, thumb_area.Height);
dc.FillRectangle (SystemBrushes.ControlLight, channel_startpoint.X + 3, channel_startpoint.Y,
1, thumb_area.Height);
}
#endregion