protected virtual void TrackBarDrawHorizontalThumbTop (Graphics dc, Rectangle thumb_pos, Brush br_thumb, Rectangle clippingArea, TrackBar trackBar)
{
Pen pen = SystemPens.ControlLightLight;
dc.DrawLine (pen, thumb_pos.X, thumb_pos.Y + 4, thumb_pos.X, thumb_pos.Y + 4 + 16);
dc.DrawLine (pen, thumb_pos.X, thumb_pos.Y + 4, thumb_pos.X + 4, thumb_pos.Y);
pen = SystemPens.ControlDark;
dc.DrawLine (pen, thumb_pos.X + 9, thumb_pos.Y + 4, thumb_pos.X + 9, thumb_pos.Y + 4 + 16);
dc.DrawLine (pen, thumb_pos.X + 9, thumb_pos.Y + 4, thumb_pos.X + 5, thumb_pos.Y);
dc.DrawLine (pen, thumb_pos.X + 9, thumb_pos.Y + 19, thumb_pos.X + 1, thumb_pos.Y + 19);
pen = SystemPens.ControlDarkDark;
dc.DrawLine (pen, thumb_pos.X + 10, thumb_pos.Y + 4, thumb_pos.X + 10, thumb_pos.Y + 4 + 16);
dc.DrawLine (pen, thumb_pos.X + 10, thumb_pos.Y + 4, thumb_pos.X + 5, thumb_pos.Y - 1);
dc.DrawLine (pen, thumb_pos.X, thumb_pos.Y + 20, thumb_pos.X + 10, thumb_pos.Y + 20);
dc.FillRectangle (br_thumb, thumb_pos.X + 1, thumb_pos.Y + 4, 8, 15);
dc.FillRectangle (br_thumb, thumb_pos.X + 2, thumb_pos.Y + 3, 6, 1);
dc.FillRectangle (br_thumb, thumb_pos.X + 3, thumb_pos.Y + 2, 4, 1);
dc.FillRectangle (br_thumb, thumb_pos.X + 4, thumb_pos.Y + 1, 2, 1);
}