C# 中GDI+绘图 局部放大的做法 高手请帮忙

[shamohai5566]

我用GDI+作图，图的内容是一个坐标轴，然后用一个游标（一条竖线）去指示从单片机中读取的示数，达到动态显示的目的。这里由于有3个游标，为了能够清晰地看出3个游标之间的相对位置，我决定做一个局部放大的功能。不知如何做，查资料也没有什么收获。绘图代码代码如下，望高手指点，在线等，谢谢

            Pen pen = new Pen(Color.Black, 1);
            Pen penNow = new Pen(Color.Green, 1);
            penNow.EndCap = LineCap.ArrowAnchor;
            Pen penMax = new Pen(Color.Red, 1);
            penMax.EndCap = LineCap.ArrowAnchor;
            Pen penMin = new Pen(Color.Blue, 1);
            penMin.EndCap = LineCap.ArrowAnchor;
            System.Drawing.Font font = new System.Drawing.Font("Arial", 8, FontStyle.Regular);
            Graphics g = e.Graphics;
            g.DrawLine(pen, 0, 45, 700, 45);
            String[] n = { "0%", "10%", "20%", "30%", "40%", "50%", "60%", "70%", "80%", "90%", "100%" };
            int xstart = 10;
            for (int i = 0; i < 11; i++)
            {
                g.DrawString(n[i], font, Brushes.DarkGray, xstart - 7, 45);
                int Xmin = xstart;
                for (int j = 0; j < 9; j++)
                {
                    Xmin += 6;
                    if (j == 4) g.DrawLine(pen, Xmin, 37, Xmin, 45);
                    else g.DrawLine(pen, Xmin, 41, Xmin, 45);
                }
                g.DrawLine(pen, xstart, 35, xstart, 45);
                xstart = xstart + 60;
                Thread.Sleep(1);
            }
            g.DrawLine(penMax, xMax, 30, xMax, 45);
            g.DrawLine(penMin, xMin, 30, xMin, 45);
            g.DrawLine(penNow, x1, 30, x1, 45);