C# 实现Bresenham算法（vs2010） 

  1 using System;
  2 
  3 using System.Collections.Generic;
  4 
  5 using System.ComponentModel;
  6 
  7 using System.Data;
  8 
  9 using System.Linq;
 10 
 11 using System.Text;
 12 
 13 using System.Windows.Forms;
 14 
 15 using System.Drawing;
 16 
 17 using System.Drawing.Drawing2D;
 18 
 19  
 20 
 21 namespace Bresenham
 22 
 23 {
 24 
 25     public partial class Form1 : Form
 26 
 27     {
 28 
 29         Graphics g;
 30 
 31         const int CellSize = 20;
 32 
 33         int iclick = 0;
 34 
 35         int Cols, Rows;
 36 
 37         Point A,B;
 38 
 39  
 40 
 41         public Form1()
 42 
 43         {
 44 
 45             InitializeComponent();
 46 
 47             g = CreateGraphics();
 48 
 49             Rows = this.Height / 20;
 50 
 51             Cols = this.Width / 20;
 52 
 53         }
 54 
 55  
 56 
 57         private void Form1_Load(object sender, EventArgs e)
 58 
 59         {
 60 
 61         }
 62 
 63  
 64 
 65         private void Form1_Paint(object sender, PaintEventArgs e)//程序启动时调用一次DrawSence()
 66 
 67         {
 68 
 69             DrawSence();
 70 
 71         }
 72 
 73  
 74 
 75         private void DrawSence()//绘制背景网格
 76 
 77         {
 78 
 79             int i, j;
 80 
 81             Point M, N;
 82 
 83             Pen p = new Pen(Brushes.Black, 1);
 84 
 85             g.Clear(Color.White);
 86 
 87             for (i = 0; i < Rows   1; i )
 88 
 89             {
 90 
 91                 M = new Point(0, i * CellSize);
 92 
 93                 N = new Point(Width, i * CellSize);
 94 
 95                 g.DrawLine(p, M, N);
 96 
 97             }
 98 
 99             for (j = 0; j < Cols   1; j )
100 
101             {
102 
103                 M = new Point(j * CellSize, 0);
104 
105                 N = new Point(j * CellSize, Height);
106 
107                 g.DrawLine(p, M, N);
108 
109             }                        
110 
111         }
112 
113  
114 
115         private void Form1_MouseClick(object sender, MouseEventArgs e)//记录鼠标坐标，并绘制位置
116 
117         {
118 
119             switch (iclick)
120 
121             {
122 
123                 case 0:
124 
125                     {
126 
127                         A = new Point(e.X / CellSize, e.Y / CellSize);
128 
129                         DrawSence();
130 
131                         g.FillEllipse(Brushes.Red, A.X * CellSize, A.Y * CellSize, CellSize, CellSize);
132 
133                         iclick = 1;
134 
135                         break;
136 
137                     }
138 
139                 case 1:
140 
141                     {
142 
143                         B = new Point(e.X / CellSize, e.Y / CellSize);
144 
145                         DoBresenham(A,B);
146 
147                         g.FillEllipse(Brushes.Red, B.X * CellSize, B.Y * CellSize, CellSize, CellSize);
148 
149                         g.FillEllipse(Brushes.Red, A.X * CellSize, A.Y * CellSize, CellSize, CellSize);
150 
151                         iclick = 0;
152 
153                         break;
154 
155                     }
156 
157             }
158 
159         }
160 
161         private void DoBresenham(Point p1,Point p2)//实现Bresenham算法，绘制离散像素点
162 
163         {
164 
165             int dx = p2.X - p1.X;
166 
167             int dy = p2.Y - p1.Y;
168 
169             int stepX = 0, stepY = 0;
170 
171             if (dx < 0)
172 
173             {
174 
175                 dx = -dx;
176 
177                 stepX = -1;
178 
179             }
180 
181             else
182 
183                 stepX = 1;
184 
185             if (dy < 0)
186 
187             {
188 
189                 dy = -dy;
190 
191                 stepY = -1;
192 
193             }
194 
195             else
196 
197                 stepY = 1;
198 
199  
200 
201             if (dx > dy)
202 
203             {
204 
205                 int y = p1.Y;
206 
207                 int d = 2 * dy - dx;
208 
209                 for (int i = p1.X; i != p2.X; i  = stepX)
210 
211                 {
212 
213                     g.FillEllipse(Brushes.Blue, i * CellSize, y * CellSize, 20, 20);
214 
215                     d = d   2 * dy;
216 
217                     if (d >= 0)
218 
219                     {
220 
221                         y  = stepY;
222 
223                         d = d - 2 * dx;
224 
225                     }
226 
227                 }
228 
229             }
230 
231             else
232 
233             {
234 
235                 int x = p1.X;
236 
237                 int d = 2 * dx - dy;
238 
239                 for (int i = p1.Y; i != p2.Y; i  = stepY)
240 
241                 {
242 
243                     g.FillEllipse(Brushes.Blue, x * CellSize, i * CellSize, 20, 20);
244 
245                     d = d   2 * dx;
246 
247                     if (d >= 0)
248 
249                     {
250 
251                         x  = stepX;
252 
253                         d = d - 2 * dy;
254 
255                     }
256 
257                 }
258 
259             }                                       
260 
261         }
262 
263     }
264 
265 }

 

posted @ 2014-05-16 23:15  青山应回首  阅读(818)  评论(0)  编辑  收藏  举报