System.Drawing.Drawing2D.GraphicsPath.AddBezier C# (CSharp) Method

        public void AddBezier(int x1, int y1, int x2, int y2, int x3, int y3, int x4, int y4)
        {
            Append (x1, y1, PathPointType.Line, true);
            AppendBezier (x2, y2, x3, y3, x4, y4);
        }

        /// <summary>
        /// Gets the tab path.
        /// </summary>
        /// <param name="index">The index.</param>
        /// <returns>GraphicsPath.</returns>
        private GraphicsPath GetTabPath(int index)
        {
            System.Drawing.Drawing2D.GraphicsPath path = new System.Drawing.Drawing2D.GraphicsPath();
            path.Reset();
            Rectangle rect = this.GetTabRect(index);

            switch (Alignment)
            {
            case TabAlignment.Top:

                break;

            case TabAlignment.Bottom:

                break;

            case TabAlignment.Left:

                break;

            case TabAlignment.Right:

                break;
            }
            int PaddingTop = 10;

            Point P_LeftTop     = new Point(rect.Left + 7, rect.Top + PaddingTop);
            Point P_LeftBottom  = new Point(rect.Left + 1, rect.Bottom);
            Point P_RightTop    = new Point(rect.Right - 7, rect.Top + PaddingTop);
            Point P_RightBottom = new Point(rect.Right - 1, rect.Bottom);

            Point P_Control1 = new Point(rect.Left + 3, rect.Top + PaddingTop);
            Point P_Control2 = new Point(rect.Left + 2, rect.Bottom - rect.Height / 2);

            Point P_Control3 = new Point(rect.Right - 3, rect.Top + PaddingTop);
            Point P_Control4 = new Point(rect.Right - 2, rect.Bottom - rect.Height / 2);

            //path.AddLine(rect.Left + 15, rect.Top, rect.Left + 2, rect.Bottom + 1);
            //path.AddLine(rect.Left + 15, rect.Top, rect.Right - 15, rect.Top);
            //path.AddLine(rect.Right - 15, rect.Top, rect.Right - 2, rect.Bottom + 1);
            //path.AddLine(rect.Right - 2, rect.Bottom, rect.Left + 2, rect.Bottom);
            path.AddBezier(P_LeftTop, P_Control1, P_Control2, P_LeftBottom);
            path.AddLine(P_LeftBottom, P_RightBottom);
            path.AddBezier(P_RightBottom, P_Control4, P_Control3, P_RightTop);
            //path.AddBezier(P_RightTop, P_Control3, P_Control4, P_RightBottom);
            path.AddLine(P_RightTop, P_LeftTop);



            //int diameter = 2 * 10;

            //path.AddArc(new Rectangle(new Point(rect.Left + 5, rect.Top), new Size(diameter, diameter)), 180, 60);
            //path.AddArc(new Rectangle(new Point(rect.Right - 15 - diameter, rect.Top - diameter), new Size(diameter, diameter)), 0, 60);
            path.CloseFigure();
            //return GetRoundedRectPath(rect, 15);
            return(path);
        }