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