灯光的测试例子：光源参数可以调节的测试场景
先看一下测试场景和效果。
场景中可以切换视图， 以方便观察三维体和灯光的位置。环境光，漫射光，镜面反射光都可以在四种颜色间切换。
灯光位置和摄像机位置(LookAt)可以输入数值或者点动调节，也可以按键盘的QEWASD六个键进行调节。
你还会注意到：球体对光的效果要敏感柔和些，而那个六面体BOX看来效果不好。这是因为灯光对顶点发生作用。在程序里面，球休的顶点数量有20*10，而BOX只有4*6个，而且还重合了一些顶点。
这一点，在3dsmax的全局光照里面表现很明显，做为墙壁的box顶点数量越大，计算出来光照效果越好。
还有，界面上灯光位置是 -1,5,1,1 前三个是x,y,z， 后面的一个1不是坐标，它取值0或者1，表示灯光是定向光源(directonal)，还是定位光源(positional)。
代码如下：
1 using System;
2 using System.Collections.Generic;
3 using System.ComponentModel;
4 using System.Data;
5 using System.Drawing;
6 using System.Linq;
7 using System.Text;
8 using System.Windows.Forms;
9 using SharpGL;
10
11 namespace SharpGLWinformsApplication1
12 {
13
14 public partial class SharpGLForm : Form
15 {
16 private float rotation = 0.0f;
17 private bool isRotate = false;
18 private bool isLines = false;
19 private bool isFrontView = false;
20 private bool isLeftView = false;
21 private bool isTopView = false;
22 private bool isPerspective = true;
23 private float[] lightPos = new float[] { -1, -3, 1, 1 };
24 private float[] lightSphereColor = new float[] { 1f, 1f, 1f };
25 private IList<float[]> lightColor = new List<float[]>();
26 private double[] lookatValue = { 1, 1, 2, 0, 0, 0, 0, 1, 0 };
27 private IList<double[]> viewDefaultPos = new List<double[]>();
28 public SharpGLForm()
29 {
30 InitializeComponent();
31 }
32
33 private void openGLControl_OpenGLDraw(object sender, PaintEventArgs e)
34 {
35 OpenGL gl = openGLControl.OpenGL;
36 gl.Clear(OpenGL.GL_COLOR_BUFFER_BIT | OpenGL.GL_DEPTH_BUFFER_BIT);
37 gl.LoadIdentity();
38 gl.Rotate(rotation, 0.0f, 1.0f, 0.0f);
39
40 drawGrid(gl);
41 DrawCube(ref gl, 1.5f,-1f, -2f, isLines);
42 drawOneSphere(ref gl,-3,-2,-4,isLines);
43 if (isRotate)
44 rotation += 3.0f;
45 }
46
47 private void setLightColor(OpenGL gl)
48 {
49 gl.Light(OpenGL.GL_LIGHT0, OpenGL.GL_AMBIENT, lightColor[0]);
50 gl.Light(OpenGL.GL_LIGHT0, OpenGL.GL_DIFFUSE, lightColor[1]);
51 gl.Light(OpenGL.GL_LIGHT0, OpenGL.GL_SPECULAR, lightColor[2]);
52 }
53
54 private void openGLControl_OpenGLInitialized(object sender, EventArgs e)
55 {
56 OpenGL gl = openGLControl.OpenGL;
57
58 //四个视图的缺省位置
59 viewDefaultPos.Add(new double[] { 1, 1, 2, 0, 0, 0, 0, 1, 0 }); //透视
60 viewDefaultPos.Add(new double[] { 0, 0, 2, 0, 0, 0, 0, 1, 0 }); //前视
61 viewDefaultPos.Add(new double[] { 5, 0, 0, 0, 0, 0, 0, 1, 0 }); //左视
62 viewDefaultPos.Add(new double[] { 0, 13, 0, -1, 0, 0, 0, 1, 0 }); //顶视
63 lookatValue =(double[])viewDefaultPos[0].Clone();
64
65 lightColor.Add(new float[] { 1f, 1f, 1f, 1f }); //环境光(ambient light)
66 lightColor.Add(new float[] { 1f, 1f, 1f, 1f }); //漫射光(diffuse light)
67 lightColor.Add(new float[] { 1f, 1f, 1f, 1f }); //镜面反射光(specular light)
68
69 setLightColor(gl);
70 gl.Light(OpenGL.GL_LIGHT0, OpenGL.GL_POSITION, lightPos);
71
72 gl.Enable(OpenGL.GL_LIGHTING);
73 gl.Enable(OpenGL.GL_LIGHT0);
74
75 gl.ClearColor(0, 0, 0, 0);
76 }
77
78 private void drawOneSphere(ref OpenGL gl, float xPos, float yPos, float zPos, bool isLine)
79 {
80 gl.PushMatrix();
81 {
82 gl.Translate(xPos, yPos, zPos);
83 gl.Color(lightSphereColor);
84 drawSphere(gl,1,20,10,isLine);
85 }
86 gl.PopMatrix();
87 }
88
89 private void openGLControl_Resized(object sender, EventArgs e)
90 {
91
92 OpenGL gl = openGLControl.OpenGL;
93 gl.MatrixMode(OpenGL.GL_PROJECTION);
94 gl.LoadIdentity();
95 gl.Perspective(40.0f, (double)Width / (double)Height, 0.01, 100.0);
96
97
98 gl.LookAt(lookatValue[0], lookatValue[1], lookatValue[2],
99 lookatValue[3], lookatValue[4], lookatValue[5],
100 lookatValue[6], lookatValue[7], lookatValue[8]);
101
102 gl.MatrixMode(OpenGL.GL_MODELVIEW);
103 updateLabInfo();
104 }
105
106 internal void DrawCube(ref OpenGL Gl, float xPos, float yPos, float zPos, bool isLine)
107 {
108 Gl.PushMatrix();
109 Gl.Translate(xPos, yPos, zPos);
110 if (isLine)
111 Gl.Begin(OpenGL.GL_LINE_STRIP);
112 else
113 Gl.Begin(OpenGL.GL_POLYGON);
114
115 /** 顶面 */
116 Gl.Vertex(0.0f, 0.0f, 0.0f);
117 Gl.Vertex(0.0f, 0.0f, -1.0f);
118 Gl.Vertex(-1.0f, 0.0f, -1.0f);
119 Gl.Vertex(-1.0f, 0.0f, 0.0f);
120
121 /** 前面 */
122 Gl.Vertex(0.0f, 0.0f, 0.0f);
123 Gl.Vertex(-1.0f, 0.0f, 0.0f);
124 Gl.Vertex(-1.0f, -1.0f, 0.0f);
125 Gl.Vertex(0.0f, -1.0f, 0.0f);
126
127 /** 右面 */
128 Gl.Vertex(0.0f, 0.0f, 0.0f);
129 Gl.Vertex(0.0f, -1.0f, 0.0f);
130 Gl.Vertex(0.0f, -1.0f, -1.0f);
131 Gl.Vertex(0.0f, 0.0f, -1.0f);
132
133 /** 左面*/
134 Gl.Vertex(-1.0f, 0.0f, 0.0f);
135 Gl.Vertex(-1.0f, 0.0f, -1.0f);
136 Gl.Vertex(-1.0f, -1.0f, -1.0f);
137 Gl.Vertex(-1.0f, -1.0f, 0.0f);
138
139 /** 底面 */
140 Gl.Vertex(0.0f, 0.0f, 0.0f);
141 Gl.Vertex(0.0f, -1.0f, -1.0f);
142 Gl.Vertex(-1.0f, -1.0f, -1.0f);
143 Gl.Vertex(-1.0f, -1.0f, 0.0f);
144
145
146 /** 后面 */
147 Gl.Vertex(0.0f, 0.0f, 0.0f);
148 Gl.Vertex(-1.0f, 0.0f, -1.0f);
149 Gl.Vertex(-1.0f, -1.0f, -1.0f);
150 Gl.Vertex(0.0f, -1.0f, -1.0f);
151 Gl.End();
152 Gl.PopMatrix();
153 }
154
155 void drawGrid(OpenGL gl)
156 {
157 //绘制过程
158 gl.PushAttrib(OpenGL.GL_CURRENT_BIT); //保存当前属性
159 gl.PushMatrix(); //压入堆栈
160 gl.Translate(0f, -2f, 0f);
161 gl.Color(0f, 0f, 1f);
162
163 //在X,Z平面上绘制网格
164 for (float i = -50; i <= 50; i += 1)
165 {
166 //绘制线
167 gl.Begin(OpenGL.GL_LINES);
168 {
169 if (i == 0)
170 gl.Color(0f, 1f, 0f);
171 else
172 gl.Color(0f, 0f, 1f);
173
174 //X轴方向
175 gl.Vertex(-50f, 0f, i);
176 gl.Vertex(50f, 0f, i);
177 //Z轴方向
178 gl.Vertex(i, 0f, -50f);
179 gl.Vertex(i, 0f, 50f);
180
181 }
182 gl.End();
183 }
184 gl.PopMatrix();
185 gl.PopAttrib();
186 }
187
188
189 void drawSphere(OpenGL gl,double radius,int segx,int segy,bool isLines)
190 {
191 gl.PushMatrix();
192 gl.Translate(2f, 1f, 2f);
193 var sphere = gl.NewQuadric();
194 if (isLines)
195 gl.QuadricDrawStyle(sphere, OpenGL.GL_LINES);
196 else
197 gl.QuadricDrawStyle(sphere, OpenGL.GL_QUADS);
198 gl.QuadricNormals(sphere, OpenGL.GLU_SMOOTH);
199 gl.QuadricOrientation(sphere, (int)OpenGL.GLU_OUTSIDE);
200 gl.QuadricTexture(sphere, (int)OpenGL.GLU_FALSE);
201 gl.Sphere(sphere, radius, segx, segy);
202 gl.DeleteQuadric(sphere);
203 gl.PopMatrix();
204 }
205
206 private void moveObject(int obj,string keyName)
207 {
208 //obj==0移动视图
209 switch (keyName)
210 {
211 case "btnQ":
212 if (obj == 0) ++lookatValue[1]; //y
213 else
214 ++lightPos[1];
215 break;
216 case "btnE":
217 if (obj == 0) --lookatValue[1];
218 else
219 --lightPos[1];
220 break;
221 case "btnW":
222 if (obj == 0) --lookatValue[2]; //z
223 else
224 --lightPos[2];
225 break;
226 case "btnS":
227 if (obj == 0) ++lookatValue[2];
228 else
229 ++lightPos[2];
230 break;
231 case "btnA":
232 if (obj == 0) --lookatValue[0]; //X
233 else
234 --lightPos[0];
235 break;
236 case "btnD":
237 if (obj == 0) ++lookatValue[0];
238 else
239 ++lightPos[0];
240 break;
241 }
242 }
243
244 private void rbPerspective_CheckedChanged(object sender, EventArgs e)
245 {
246 switch (((RadioButton)sender).Name)
247 {
248 case "rbPerspective":
249 isPerspective = !isPerspective;
250 isFrontView = false;
251 isTopView = false;
252 isLeftView = false;
253 break;
254 case "rbLeft":
255 isLeftView = !isLeftView;
256 isFrontView = false;
257 isPerspective = false;
258 isTopView = false;
259 break;
260 case "rbFront":
261 isFrontView = !isFrontView;
262 isTopView = false;
263 isPerspective = false;
264 isLeftView = false;
265 break;
266 case "rbTop":
267 isTopView = !isTopView;
268 isPerspective = false;
269 isLeftView = false;
270 isFrontView = false;
271 break;
272 default:
273 return;
274 }
275 setViewDefaultValue();
276 openGLControl_Resized(null, null);
277 }
278
279 private void cbxRotate_CheckedChanged(object sender, EventArgs e)
280 {
281 var cbx=((CheckBox)sender);
282 switch (cbx.Name)
283 {
284 case "cbxRotate":
285 isRotate = cbx.Checked;
286 break;
287 case "cbxLines":
288 isLines = cbx.Checked;
289 break;
290 case "cbxLightOff":
291 if (!cbx.Checked)
292 this.openGLControl.OpenGL.Enable(OpenGL.GL_LIGHT0);
293 else
294 this.openGLControl.OpenGL.Disable(OpenGL.GL_LIGHT0);
295 break;
296 }
297 }
298
299 private void SharpGLForm_Load(object sender, EventArgs e)
300 {
301 this.cbxLightType.SelectedIndex = 0;
302 updateLabInfo();
303 }
304
305 private void updateLabInfo()
306 {
307 tbLightPos.Text = string.Format("{0},{1},{2},{3}", lightPos[0], lightPos[1], lightPos[2], lightPos[3]);
308 tbLookAt.Text = string.Format("{0},{1},{2},{3},{4},{5},{6},{7},{8}", lookatValue[0], lookatValue[1], lookatValue[2],
309 lookatValue[3], lookatValue[4], lookatValue[5], lookatValue[6], lookatValue[7], lookatValue[8]);
310 }
311
312 private void rbWhite_CheckedChanged(object sender, EventArgs e)
313 {
314 var rad = ((RadioButton)sender);
315 var lightType = this.cbxLightType.SelectedIndex;
316 if (rad.Checked)
317 {
318 switch (rad.Name)
319 {
320 case "rbWhite":
321 lightColor[lightType][0] = 1f;
322 lightColor[lightType][1] = 1f;
323 lightColor[lightType][2] = 1f;
324 lightColor[lightType][3] = 1f;
325 break;
326 case "rbRed":
327 lightColor[lightType][0] = 1f;
328 lightColor[lightType][1] = 0f;
329 lightColor[lightType][2] = 0f;
330 lightColor[lightType][3] = 1f;
331 break;
332 case "rbGreen":
333 lightColor[lightType][0] = 0f;
334 lightColor[lightType][1] = 1f;
335 lightColor[lightType][2] = 0f;
336 lightColor[lightType][3] = 1f;
337 break;
338 case "rbBlue":
339 lightColor[lightType][0] = 0f;
340 lightColor[lightType][1] = 0f;
341 lightColor[lightType][2] = 1f;
342 lightColor[lightType][3] = 1f;
343 break;
344 }
345 setLightColor(openGLControl.OpenGL);
346 }
347 }
348
349 private void cbxLightType_SelectedIndexChanged(object sender, EventArgs e)
350 {
351 var lightType = this.cbxLightType.SelectedIndex;
352 if (lightType >= 0)
353 judgeColor(lightColor[lightType]);
354 }
355
356 private void judgeColor(float[] color)
357 {
358 if (color[0] == 1f && color[1] == 1f && color[2] == 1f && color[3] == 1f)
359 rbWhite.Checked = true;
360 else if (color[0] == 1f && color[1] == 0f && color[2] == 0f && color[3] == 1f)
361 rbRed.Checked = true;
362 else if (color[0] == 0f && color[1] == 1f && color[2] == 0f && color[3] == 1f)
363 rbGreen.Checked = true;
364 else if (color[0] == 0f && color[1] == 0f && color[2] == 1f && color[3] == 1f)
365 rbBlue.Checked = true;
366 }
367
368 private void btnQ_Click(object sender, EventArgs e)
369 {
370 moveObject(radioButton1.Checked ? 0 : 1,((Button)sender).Name);
371 openGLControl_Resized(null, null);
372 openGLControl.OpenGL.Light(OpenGL.GL_LIGHT0, OpenGL.GL_POSITION, lightPos);
373 }
374
375 private void setViewDefaultValue()
376 {
377 if (isPerspective)
378 {
379 lookatValue = (double[])viewDefaultPos[0].Clone();
380 }
381 else if (isFrontView)
382 {
383 lookatValue = (double[])viewDefaultPos[1].Clone();
384 }
385 else if (isLeftView)
386 {
387 lookatValue = (double[])viewDefaultPos[2].Clone();
388 }
389 else if (isTopView)
390 {
391 lookatValue = (double[])viewDefaultPos[3].Clone();
392 }
393 }
394
395 private void btnDefaultPOS_Click(object sender, EventArgs e)
396 {
397 if (radioButton1.Checked)
398 {
399 setViewDefaultValue();
400 }
401 else
402 {
403 lightPos = new float[] { -1, -3, 1, 1 };
404 openGLControl.OpenGL.Light(OpenGL.GL_LIGHT0, OpenGL.GL_POSITION, lightPos);
405 }
406 openGLControl_Resized(null, null);
407 }
408
409 private void openGLControl_KeyDown(object sender, KeyEventArgs e)
410 {
411 string name = string.Empty;
412 switch (e.KeyCode)
413 {
414 case Keys.W:
415 name = "btnW";
416 break;
417 case Keys.A:
418 name = "btnA";
419 break;
420 case Keys.S:
421 name = "btnS";
422 break;
423 case Keys.D:
424 name = "btnD";
425 break;
426 case Keys.Q:
427 name = "btnQ";
428 break;
429 case Keys.E:
430 name = "btnE";
431 break;
432 }
433 moveObject(radioButton1.Checked ? 0 : 1, name);
434 openGLControl_Resized(null, null);
435 }
436
437 private void btnSetPos_Click(object sender, EventArgs e)
438 {
439 if (radioButton1.Checked)
440 {
441 double[] ary = tbLookAt.Text.Split(‘,‘).Select(s => Convert.ToDouble(s)).ToArray();
442 lookatValue = ary;
443 openGLControl_Resized(null, null);
444 }
445 else
446 {
447 float[] ary = tbLightPos.Text.Split(‘,‘).Select(s => Convert.ToSingle(s)).ToArray();
448 lightPos = ary;
449 openGLControl.OpenGL.Light(OpenGL.GL_LIGHT0, OpenGL.GL_POSITION, ary);
450 }
451
452 }
453
454
455 }
456 }
有关灯光的代码如下粗体显示部分：
1 private void setLightColor(OpenGL gl)
2 {
3 gl.Light(OpenGL.GL_LIGHT0, OpenGL.GL_AMBIENT, lightColor[0]);
4 gl.Light(OpenGL.GL_LIGHT0, OpenGL.GL_DIFFUSE, lightColor[1]);
5 gl.Light(OpenGL.GL_LIGHT0, OpenGL.GL_SPECULAR, lightColor[2]);
6 }
7
8 private void openGLControl_OpenGLInitialized(object sender, EventArgs e)
9 {
10 OpenGL gl = openGLControl.OpenGL;
11
12 //四个视图的缺省位置
13 viewDefaultPos.Add(new double[] { 1, 1, 2, 0, 0, 0, 0, 1, 0 }); //透视
14 viewDefaultPos.Add(new double[] { 0, 0, 2, 0, 0, 0, 0, 1, 0 }); //前视
15 viewDefaultPos.Add(new double[] { 5, 0, 0, 0, 0, 0, 0, 1, 0 }); //左视
16 viewDefaultPos.Add(new double[] { 0, 13, 0, -1, 0, 0, 0, 1, 0 }); //顶视
17 lookatValue =(double[])viewDefaultPos[0].Clone();
18
19 lightColor.Add(new float[] { 1f, 1f, 1f, 1f }); //环境光(ambient light)
20 lightColor.Add(new float[] { 1f, 1f, 1f, 1f }); //漫射光(diffuse light)
21 lightColor.Add(new float[] { 1f, 1f, 1f, 1f }); //镜面反射光(specular light)
22
23 setLightColor(gl);
24 gl.Light(OpenGL.GL_LIGHT0, OpenGL.GL_POSITION, lightPos);
25
26 gl.Enable(OpenGL.GL_LIGHTING);
27 gl.Enable(OpenGL.GL_LIGHT0);
28
29 gl.ClearColor(0, 0, 0, 0);
30 }
第3,4,5行是创建灯光三个部分 环境光，漫射光，镜面反射光。
第24行是设定灯光的位置。
第26,27是让灯光开，有效。
灯光代码确实比较简单，这段代码其它部分没什么好说的，笔者按界面功能直述其意，朋友们应该很容易懂。
唯一要关注下的是：视图和灯光的参数修改是如何实时生效的。
原创文章,出自"博客园, 猪悟能‘S博客" : http://www.cnblogs.com/hackpig/
时间： 2024-10-14 04:57:39