private void PlotPanelPaint(object sender, PaintEventArgs e)
        {
            Graphics g         = e.Graphics;
            var      borderPen = new Pen(Brushes.Black, 1);

            g.DrawRectangle(borderPen, panel1.Bounds.X, panel1.Bounds.Y, panel1.Bounds.Width, panel1.Bounds.Height);
            borderPen.Dispose();

            g.SmoothingMode = SmoothingMode.AntiAlias;
            float a;

            if (panel1.Height < panel1.Width)
            {
                a = panel1.Height / 3;
            }
            else
            {
                a = panel1.Height / 4;
            }

            DrawSphere ds = new DrawSphere(this, a, 0, 0, -a / 2);

            ds.DrawIsometricView(g);
            ds = new DrawSphere(this, 2 * a / 3, -a / 2, -a / 2, a / 2);
            ds.DrawIsometricView(g);
        }
        private void PlotPanelPaint(object sender, PaintEventArgs e)
        {
            Graphics g = e.Graphics;
            var borderPen = new Pen(Brushes.Black,1);
            g.DrawRectangle(borderPen,panel1.Bounds);
            borderPen.Dispose();

            g.SmoothingMode = SmoothingMode.AntiAlias;
            float a;

            if (panel1.Height < panel1.Width)
                a = panel1.Height / 3;
            else
                a = panel1.Height / 4;

            DrawSphere ds = new DrawSphere(this, a, 0, 0, -a / 2);
            ds.DrawIsometricView(g);
            ds = new DrawSphere(this, 2 * a / 3, -a/2, -a/2, a / 2);
            ds.DrawIsometricView(g);
        }