B样条实现代码

用GDI+设计B样条实现代码，对于给定的多个控制点，生成平滑曲线，

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Drawing.Imaging ;
using System.Drawing.Drawing2D ;
using System.IO;

namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        public double[] splinex = new double[1001];
        public double[] spliney = new double[1001];
        public point[] pt = new point[6];
        public int no_of_points = 0;
        int[] a1 = new int[12];
        int[] b1 = new int[12];
       
         public Form1（）
        {
            InitializeComponent（）;
            
        }
        public struct point
        {
            public int x;
            public int y;

            public void setxy（int i int j）
            {
                x = i;
                y = j;
            }
        }  

        // Prints a dot at the place whrere the mouseup event occurs 
        private void pictureBox1_MouseUp（object sender MouseEventArgs e）
        {
            Graphics g = pictureBox1.CreateGraphics（）;
            Color cl=Color.Black;
            g.DrawLine （new Pen（cl 2） e.X e.Y e.X+1   e.Y+1  ）;

        }

        // At each mousedown event the the no of points is calculated if the value is more than 3
        //then the curve is drawn
        private void pictureBox1_MouseDown（object sender MouseEventArgs e）
        {
            	if （no_of_points > 3）
				{					
					pt[0] = pt[1];pt[1] = pt[2];pt[2] = pt[3];
                    pt[3].setxy（e.X e.Y）;
                    double temp = Math.Sqrt（Math.Pow（pt[2].x - pt[1].x 2F） + Math.Pow（pt[2].y - pt[1].y 2F））;
					int interpol = System.Convert.ToInt32（temp）;
					bsp（pt[0]pt[1]pt[2]pt[3]interpol）;
					int i; 
                    int width=2;
                    Graphics g = pictureBox1.CreateGraphics（）;
                    Color cl=Color.Blue;
                    int xy;
                    // the lines are drawn
					for （i = 0; i <= interpol - 1; i++）
					{
					 x=System.Convert.ToInt32（splinex[i]）;
                     y=System.Convert.ToInt32（spliney[i]）;                    
                     g.DrawLine（  new Pen（cl width）  x - 1 y x + 1 y）;
                      g.DrawLine（new Pen（cl width） x y - 1 x y + 1）;
                               
                    }				
				}
				else
				{
					pt[no_of_points].setxy（e.X e.Y）;
				}				
				no_of_points = no_of_points + 1;			 
			 
        }
         
        // calculating the values using the algorithm 
        public void bsp（point p1 point p2 point p3 point p4 int divisions）
        {
            double[] a = new double[5];
            double[] b = new double[5];
            a[0] = （-p1.x + 3 * p2.x - 3 * p3.x + p4.x） / 6.0;
            a[1] = （3 * p1.x - 6 * p2.x + 3 * p3.x） / 6.0;
            a[2] = （-3 * p1.x + 3 * p3.x） / 6.0;
            a[3] = （p1.x + 4 * p2.x + p3.x） / 6.0

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----
     文件         946  2006-12-07 19:45  WindowsApplication1\WindowsApplication1.sln
     文件        8704  2006-12-07 19:45  WindowsApplication1\WindowsApplication1.suo
     目录           0  2006-12-07 19:44  WindowsApplication1\WindowsApplication1\
     目录           0  2006-12-07 19:44  WindowsApplication1\WindowsApplication1\bin\
     目录           0  2006-12-07 19:44  WindowsApplication1\WindowsApplication1\bin\Debug\
     文件       20480  2006-12-08 00:40  WindowsApplication1\WindowsApplication1\bin\Debug\WindowsApplication1.exe
     文件        5632  2005-09-23 06:56  WindowsApplication1\WindowsApplication1\bin\Debug\WindowsApplication1.vshost.exe
     文件        3678  2006-12-08 00:40  WindowsApplication1\WindowsApplication1\Form1.cs
     文件        2536  2006-12-08 00:40  WindowsApplication1\WindowsApplication1\Form1.Designer.cs
     文件        5814  2006-12-08 00:40  WindowsApplication1\WindowsApplication1\Form1.resx
     文件         486  2006-12-07 19:44  WindowsApplication1\WindowsApplication1\Program.cs
     目录           0  2006-12-07 19:44  WindowsApplication1\WindowsApplication1\Properties\
     文件        1294  2006-12-07 19:44  WindowsApplication1\WindowsApplication1\Properties\AssemblyInfo.cs
     文件        2865  2006-12-07 19:44  WindowsApplication1\WindowsApplication1\Properties\Resources.Designer.cs
     文件        5612  2006-12-07 19:44  WindowsApplication1\WindowsApplication1\Properties\Resources.resx
     文件        1102  2006-12-07 19:44  WindowsApplication1\WindowsApplication1\Properties\Settings.Designer.cs
     文件         249  2006-12-07 19:44  WindowsApplication1\WindowsApplication1\Properties\Settings.settings
     文件        3245  2006-12-07 19:50  WindowsApplication1\WindowsApplication1\WindowsApplication1.csproj