电子科大实验3-三维图形程序设计

1、实验报告课程名称：三维图形设计学院：计算机科学与工程专业：计算机科学与技术指导教师：周川学生姓名： 学号：实验成绩：日期：2014年5月19日电子科技大学计算机学院实验中心电 子 科 技 大 学实 验 报 告一、实验三：OpenGL光照与材质编程实验二、实验室名称：主楼A2-412 实验时间：2014年5月19日 三、实验目的：1、理解OpenGL光照模型的相关原理，掌握与光照参数和对象材质设置相关的OpenGL API函数的用法，熟悉光照与材质参数设置的基本技巧；2、理解OpenGL混合（融合）的基本原理，掌握与混合相关的OpenGL API函数的用法。四、实验原理：1. openGL图形编

2、程技术原理2. 选择与拾取、光照与材质、混合与透明、纹理贴图、菜单。五、实验内容：（一）编程任务1绘制一个具有光照的房间1、 建立光照场景并为场景中的几何对象设置材质属性void CreateWorld()a. 四面墙壁 void CreateWall()b. 屋顶 void CreateCeiling()c. 地板 void CreateGround()d. 一个圆锥体和一个球体 void CreateFurnishings()e. 在房间中创建并放置两个光源 void CreateLightAndProxy(void)a) 一个是点光源b) 一个是聚光灯；c) 为光源创建代理几何体（Pro

3、xy），可以通过鼠标拖动光源代理来交互式的移动光源；2、 绘制场景void DrawWorld(void)a. 绘制四面墙壁 void DrawWall()b. 绘制屋顶 void DrawCeiling()c. 绘制地板 void DrawGround()d. 绘制屋内物品 void DrawFurnishings()e. 绘制光源代理 voidDrawLightProxy()其它要求：1、可交互式移动光源；2、可用右键菜单交互式的开启或关闭场景光照；3、可利用键盘快捷键调整球的材质属性，如辉度系数（GL_SHININESS）等。分析材质是如何影响几何对象的光照效果的。（二）编程任务2绘制一

4、个具有地板反光效果的房间利用OpenGL混合功能可以模拟地板反光效果，这需要将地板和场景中其它物体分开处理，其基本思路如下：1、首先以上下颠倒的方式来绘制出地板镜像场景(即沿着地板面将光源和场景进行镜像)；2、接者利用混合在上述镜像场景之上绘制出半透明的地板；3、最后以正常的光源和场景位置来绘制场景。参考代码如下：void RenderScene(void) glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glPushMatrix(); / 光源镜像移动到地板下，以照射这个“镜像”场景 glLightfv(GL_LIGHT0, GL_PO

5、SITION, fLightPosMirror); glPushMatrix(); /场景被镜像，同时交换正反面 glFrontFace(GL_CW); glScalef(1.0f, -1.0f, 1.0f); DrawWorldExGround(); glFrontFace(GL_CCW); glPopMatrix(); / 在镜像场景上绘制一个半透明的地板 glDisable(GL_LIGHTING); glEnable(GL_BLEND); glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); DrawGround(); glDisable

6、(GL_BLEND); glEnable(GL_LIGHTING); / 恢复正常的光照，并正确绘制场景 glLightfv(GL_LIGHT0, GL_POSITION, fLightPos); DrawWorldExGround(); glPopMatrix(); glutSwapBuffers(); 六、实验器材（设备、元器件）：电脑型号戴尔 System Inspiron N4110 笔记本电脑操作系统 Windows 8 专业版 64位 ( DirectX 11 )软件环境 Microsoft Visual Studio Express 2012 for Windows Deskto

7、p OpenGL Glut3.7七、实验步骤：1.做出具有两个光照的房间2.利用拾取做出交互的光照代理3.做出其他相关附加需求如菜单4.利用透明与变换做出反光地板八、实验数据及结果分析：（一）交互光照房间1. 代码：#include<gl/glut.h>#include<stdio.h>#define W 500/窗口宽#define H 500/窗口高#define D 50.0/因为鼠标移动数据太大，而世界坐标设定得太小，所以用D将鼠标移动增量进行缩小映射int hits,hitx,hity;/命中次数、坐标GLint viewport4;GLuint select

8、Buf512;/材质属性结构定义typedef struct matattrGLfloat ambient4;GLfloat diffuse4;GLfloat specular4;GLfloat shininess;matattr;/各种材质数据设置matattr ball=0.2,0.3,0.3,1.0,0.3,0.3,0.85,1.0,0.5,0.5,0.81,1.0,50.0;matattr cone=0.3,0.0,0.0,1.0,0.6,0.0,0.0,1.0,0.8,0.6,0.6,1.0,50.0;matattr wall=0.2,0.5,0.5,1.0,0.2,0.5,0.5,

9、1.0,0.9,0.9,0.9,1.0,100.0;matattr ceiling=0.5,0.5,0.7,1.0,0.5,0.5,0.9,1.0,0.9,0.9,0.9,1.0,100.0;matattr ground=0.9,0.0,0.4,1.0,0.9,0.0,0.4,1.0,0.9,0.9,0.9,1.0,100.0;matattr light=1.0,1.0,0.1,1.0,1.0,1.0,0.1,1.0,0.8,0.8,0.2,1.0,50.0;/0光照（点光源）属性GLfloat position0=-2.0,3.0,8.0,1.0;GLfloat ambient0=0.1,0

10、.1,0.1,1.0;GLfloat diffuse0=1.0,1.0,0.8,1.0;GLfloat specular0=1.0,1.0,1.0,1.0;/1光照（聚光灯）属性GLfloat position1=-2.0,-2.0,8.0,1.0;GLfloat ambient1=0.1,0.1,0.1,1.0;GLfloat diffuse1=1.0,1.0,0.8,1.0;GLfloat specular1=1.0,1.0,1.0,1.0;GLfloat direction1=0.0,0.0,-1.0;/法向量GLfloat normals3=1.0,0.0,0.0,0.0,1.0,0.

11、0,0.0,-1.0,0.0,0.0,-1.0,0.0,0.0,0.0,-1.0,0.0,0.0,1.0;/全局光照参数设置（不使用默认的全局光）GLfloat global_ambient=0.5,0.5,0.5,1.0;/图片贴图数组GLubyte image443;GLUquadric *p;/=/=/赋予材质函数void evmat(matattr *mat)glMaterialfv(GL_FRONT_AND_BACK,GL_AMBIENT,mat->ambient);glMaterialfv(GL_FRONT_AND_BACK,GL_DIFFUSE,mat->diffus

12、e);glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,mat->specular);glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,mat->shininess);/创建房间void CreateWall()evmat(&wall);glNormal3fv(normals0);glBegin(GL_POLYGON);/前面glVertex3f(-5.0,-5.0,0.0);glVertex3f(-5.0,5.0,0.0);glVertex3f(-5.0,5.0,10.0);glVertex3f(-5

13、.0,-5.0,10.0);glEnd();glNormal3fv(normals1);glBegin(GL_POLYGON);/左边glVertex3f(5.0,-5.0,0.0);glVertex3f(5.0,-5.0,10.0);glVertex3f(-5.0,-5.0,10.0);glVertex3f(-5.0,-5.0,0.0);glEnd();glNormal3fv(normals2);glBegin(GL_POLYGON);/右边glVertex3f(5.0,5.0,0.0);glVertex3f(-5.0,5.0,0.0);glVertex3f(-5.0,5.0,10.0);g

14、lVertex3f(5.0,5.0,10.0);glEnd();glNormal3fv(normals3);glBegin(GL_POLYGON);/后面glVertex3f(5.0,-5.0,0.0);glVertex3f(5.0,5.0,0.0);glVertex3f(5.0,5.0,10.0);glVertex3f(5.0,-5.0,10.0);glEnd();void CreateCeiling()evmat(&ceiling); glNormal3fv(normals4);glBegin(GL_POLYGON);glVertex3f(-5.0,-5.0,10.0);glVer

15、tex3f(5.0,-5.0,10.0);glVertex3f(5.0,5.0,10.0);glVertex3f(-5.0,5.0,10.0);glEnd();void CreateGround()evmat(&ground); glNormal3fv(normals5);glBegin(GL_POLYGON);glTexCoord2f(0.0,0.0);glVertex3f(-5.0,-5.0,0.0);glTexCoord2f(0.0,15.0);glVertex3f(5.0,-5.0,0.0);glTexCoord2f(15.0,15.0);glVertex3f(5.0,5.0,

16、0.0);glTexCoord2f(0.0,15.0);glVertex3f(-5.0,5.0,0.0);glEnd();void CreateFurnishings()evmat(&cone);glPushMatrix();glTranslatef(-4.0,-2.0,0.0);glutSolidCone(1.0,2.0,80,50);evmat(&ball);glTranslatef(1.0,2.0,1.0);gluSphere(p,1.0,80,50);glPopMatrix();void CreateLightAndProxy(GLenum mode)glLightfv

17、(GL_LIGHT0,GL_POSITION,position0);glLightfv(GL_LIGHT0,GL_DIFFUSE,diffuse0);glLightfv(GL_LIGHT0,GL_SPECULAR,specular0);glLightfv(GL_LIGHT0,GL_AMBIENT,ambient0);glLightfv(GL_LIGHT1,GL_POSITION,position1);glLightfv(GL_LIGHT1,GL_DIFFUSE,diffuse1);glLightfv(GL_LIGHT1,GL_SPECULAR,specular1);glLightfv(GL_L

18、IGHT1,GL_AMBIENT,ambient1);glLightfv(GL_LIGHT1,GL_SPOT_DIRECTION,direction1);glLightf(GL_LIGHT1,GL_SPOT_CUTOFF,30);glLightf(GL_LIGHT1,GL_SPOT_EXPONENT,1.0);evmat(&light);if(mode = GL_SELECT) glLoadName(1);/1是矩形，点光源glPushMatrix();glTranslatef(position00,position01,position02);glBegin(GL_POLYGON);

19、glVertex3f(0,-0.25,-0.25);glVertex3f(0,-0.25,0.25);glVertex3f(0,0.25,0.25);glVertex3f(0,0.25,-0.25);glEnd();glPopMatrix();if(mode = GL_SELECT) glLoadName(2);/2是三角形，聚光灯glPushMatrix();glTranslatef(position10,position11,position12);glBegin(GL_TRIANGLES);glVertex3f(0,-0.25,-0.25);glVertex3f(0,0.0,0.5);g

20、lVertex3f(0,0.25,-0.25);glEnd();glPopMatrix();void CreateWorld()CreateLightAndProxy(GL_RENDER);CreateWall();CreateCeiling();CreateGround();CreateFurnishings();/主display函数void display()glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);glMatrixMode(GL_PROJECTION);glLoadIdentity();gluPerspective(80.0,1.

21、0,1.0,100.0);glMatrixMode(GL_MODELVIEW);glLoadIdentity();gluLookAt(4.5,0.0,5.0, 0.0,0.0,5.0, 0.0,0.0,1.0);CreateWorld();glutSwapBuffers();/鼠标移动回调void Motion(int x,int y)if (hits=1)if (selectBuf3=1)/矩形position01+=(x-hitx)/D;position02+=(hity-y)/D;/注意y是相反的，屏幕坐标和世界坐标原点位置不同else /三角形position11+=(x-hitx)/

22、D;position12+=(hity-y)/D;else if (hits=2)position01+=(x-hitx)/D;position02+=(hity-y)/D;position11+=(x-hitx)/D;position12+=(hity-y)/D;hitx=x;/拖动后新点作为击中点hity=y;glutPostRedisplay();/鼠标操作回调void mouse(int button, int state, int x, int y) if (button = GLUT_LEFT_BUTTON && state = GLUT_DOWN) /选择模式设置

23、，3像素精度 hitx=x; hity=y; glGetIntegerv (GL_VIEWPORT, viewport); glSelectBuffer (512, selectBuf); glRenderMode(GL_SELECT); glInitNames(); glPushName(0); glMatrixMode (GL_PROJECTION); glPushMatrix ();/利用流水线投影变换，取得鼠标点击形成的小视锥里面的图元 glLoadIdentity (); gluPickMatrix (GLdouble) x, (GLdouble) (viewport3 - y),

24、3.0, 3.0,viewport); gluPerspective(80.0,1.0,1.0,100.0); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); gluLookAt(4.5,0.0,5.0, 0.0,0.0,5.0, 0.0,0.0,1.0); CreateLightAndProxy(GL_SELECT); glMatrixMode (GL_PROJECTION); glPopMatrix (); glutSwapBuffers(); hits = glRenderMode (GL_RENDER); glutPostRedisplay(

25、); /键盘回调，设置材质球参数void mykey (unsigned char key,int x, int y)switch(key)case 'w':ball.shininess=(ball.shininess>90)?100:(ball.shininess+10);break;case 'a':ball.ambient0=(ball.ambient0>0.95)?1:(ball.ambient0+0.05); ball.ambient1=(ball.ambient1>0.95)?1:(ball.ambient1+0.05); ball

26、.ambient2=(ball.ambient2>0.95)?1:(ball.ambient2+0.05); break;case 's':ball.specular0=(ball.specular0>0.95)?1:(ball.specular0+0.05); ball.specular1=(ball.specular1>0.95)?1:(ball.specular1+0.05); ball.specular2=(ball.specular2>0.95)?1:(ball.specular2+0.05); break;case 'd':b

27、all.diffuse0=(ball.diffuse0>0.95)?1:(ball.diffuse0+0.05); ball.diffuse1=(ball.diffuse1>0.95)?1:(ball.diffuse1+0.05); ball.diffuse2=(ball.diffuse2>0.95)?1:(ball.diffuse2+0.05); break;glutPostRedisplay();/菜单void mainmenu(int id)switch(id)case 1:glDisable(GL_LIGHT0);break;case 2:glEnable(GL_LI

28、GHT0);break;case 3:glDisable(GL_LIGHT1);break;case 4:glEnable(GL_LIGHT1);break; /复原case 5:glEnable(GL_LIGHT0);glEnable(GL_LIGHT1); position00=-2.0;position01=3.0;position02=8.0; position10=-2.0;position11=-2.0;position12=8.0; ball.ambient0=0.2;ball.ambient1=0.3;ball.ambient2=0.3; ball.diffuse0=0.3;b

29、all.diffuse1=0.3;ball.diffuse2=0.85; ball.specular0=0.5;ball.specular1=0.5;ball.specular2=0.81; ball.shininess=50;glutPostRedisplay();/初始化函数void init()int i,j,t;glEnable(GL_DEPTH_TEST);/选0号，1号光照glEnable(GL_LIGHTING);glEnable(GL_LIGHT0);glEnable(GL_LIGHT1);p=gluNewQuadric();gluQuadricDrawStyle(p, GLU

30、_FILL);/计算贴图数组for (i=0;i<4;i+)for (j=0;j<4;j+)t=0;if (i<2 &&j<2)|(i>=2 &&j>=2)t=255;imageij0=(GLubyte)t;imageij1=(GLubyte)t;imageij2=(GLubyte)t;/贴图参数设置glEnable(GL_TEXTURE_2D);glTexImage2D(GL_TEXTURE_2D,0,GL_RGB,4,4,0,GL_RGB,GL_UNSIGNED_BYTE,image); glTexParameterf(G

31、L_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_NEAREST);glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_NEAREST);/可以给绘制每个图元时用glTexEnvf(GL_TEXTURE_2D,GL_TEXTURE_ENV_MODE,GL_MODULATE);/设

32、置相应的纹理环境，这里使用默认的纹理环境：调制glLightModelfv(GL_LIGHT_MODEL_AMBIENT,global_ambient);/创建菜单glutCreateMenu(mainmenu);glutAddMenuEntry("关闭点光源",1);glutAddMenuEntry("开启点光源",2);glutAddMenuEntry("关闭聚光灯",3);glutAddMenuEntry("开启聚光灯",4);glutAddMenuEntry("复位",5);glutAt

33、tachMenu(GLUT_RIGHT_BUTTON);void main(int argc,char *argv)glutInit(&argc,argv);glutInitDisplayMode(GLUT_DOUBLE|GLUT_RGBA|GLUT_DEPTH);glutInitWindowSize(500,500);glutInitWindowPosition(100,100);glutCreateWindow("201206007 ");glutDisplayFunc(display); glutMouseFunc (mouse); glutMotionFun

34、c(Motion);glutKeyboardFunc(mykey);init();glutMainLoop(); 2. 结果：初始效果图 移动点光源移动聚光灯只开聚光灯只开点光源关闭所有光源菜单展示按a增加材质球的ambient环境光参数复原、按s增加材质球的specular高光参数复原，按d增加材质球的diffuse漫反射参数按w增加材质球的辉度参数（镜面反射集中）仅使用环境光，按a设置环境光参数后，球有明显变化仅使用环境光，按d设置漫反射参数后，球没有明显变化3. 分析：完成了要求；可以看出聚光灯只在锥形区域发射光线；ambient和diffuse的改变对物体的颜色反应有明显作用；spec

35、ular对镜面反射有作用；shiness对物体光泽度调整有作用；只有环境光时diffuse对物体颜色没有作用；（二）绘制一个具有地板反光效果的房间1. 代码：#include<gl/glut.h>#include<stdio.h>#define W 500#define H 500/材质结构typedef struct matattrGLfloat ambient4;GLfloat diffuse4;GLfloat specular4;GLfloat shininess;matattr;/材质参数设置matattr ball=0.2,0.3,0.3,1.0,0.3,0.

36、3,0.85,1.0,0.5,0.5,0.81,1.0,50.0;matattr cone=0.3,0.0,0.0,1.0,0.6,0.0,0.0,1.0,0.8,0.6,0.6,1.0,50.0;matattr wall=0.2,0.5,0.5,1.0,0.2,0.5,0.5,1.0,0.9,0.9,0.9,1.0,100.0;matattr ceiling=0.5,0.5,0.7,1.0,0.5,0.5,0.9,1.0,0.9,0.9,0.9,1.0,100.0;matattr ground=1.0,1.0,1.0,0.5,/半透明1.0,1.0,1.0,0.5,1.0,1.0,1.0,0

37、.5,50.0;GLUquadric *p;/0光照属性GLfloat position0=-2.0,3.0,8.0,1.0;GLfloat position1=-2.0,3.0,-8.0,1.0;GLfloat ambient0=0.1,0.1,0.1,1.0;GLfloat diffuse0=1.0,1.0,0.8,1.0;GLfloat specular0=1.0,1.0,1.0,1.0;/法向GLfloat normals3=1.0,0.0,0.0,0.0,1.0,0.0,0.0,-1.0,0.0,0.0,-1.0,0.0,0.0,0.0,-1.0,0.0,0.0,1.0;/=/=/赋

38、材质函数void evmat(matattr *mat)glMaterialfv(GL_FRONT_AND_BACK,GL_AMBIENT,mat->ambient);glMaterialfv(GL_FRONT_AND_BACK,GL_DIFFUSE,mat->diffuse);glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,mat->specular);glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,mat->shininess);/创建房间void CreateWall()evmat(&am

39、p;wall);glNormal3fv(normals0);glBegin(GL_POLYGON);/前面glVertex3f(-5.0,-5.0,0.0);glVertex3f(-5.0,5.0,0.0);glVertex3f(-5.0,5.0,10.0);glVertex3f(-5.0,-5.0,10.0);glEnd();glNormal3fv(normals1);glBegin(GL_POLYGON);/左边glVertex3f(5.0,-5.0,0.0);glVertex3f(5.0,-5.0,10.0);glVertex3f(-5.0,-5.0,10.0);glVertex3f(-

40、5.0,-5.0,0.0);glEnd();glNormal3fv(normals2);glBegin(GL_POLYGON);/右边glVertex3f(5.0,5.0,0.0);glVertex3f(-5.0,5.0,0.0);glVertex3f(-5.0,5.0,10.0);glVertex3f(5.0,5.0,10.0);glEnd();glNormal3fv(normals3);glBegin(GL_POLYGON);/后面glVertex3f(5.0,-5.0,0.0);glVertex3f(5.0,5.0,0.0);glVertex3f(5.0,5.0,10.0);glVert

41、ex3f(5.0,-5.0,10.0);glEnd();void CreateCeiling()evmat(&ceiling);glNormal3fv(normals4);glBegin(GL_POLYGON);glVertex3f(-5.0,-5.0,10.0);glVertex3f(5.0,-5.0,10.0);glVertex3f(5.0,5.0,10.0);glVertex3f(-5.0,5.0,10.0);glEnd();void CreateGround()evmat(&ground);glNormal3fv(normals5);glBegin(GL_POLYGON

42、);glVertex3f(-5.0,-5.0,0.0);glVertex3f(5.0,-5.0,0.0);glVertex3f(5.0,5.0,0.0);glVertex3f(-5.0,5.0,0.0);glEnd();void CreateFurnishings()evmat(&cone);glPushMatrix();glTranslatef(-4.0,-2.0,0.0);glutSolidCone(1.0,2.0,80,50);evmat(&ball);glTranslatef(1.0,2.0,1.0);gluSphere(p,1.0,80,50);glPopMatrix

43、();void CreateWorld()CreateWall();CreateCeiling();CreateFurnishings();void RenderScene() glPushMatrix(); glLightfv(GL_LIGHT0, GL_POSITION, position1); / 光源镜像移动到地板下，以照射这个“镜像”场景 glPushMatrix(); glScalef(1.0f, 1.0f, -1.0f);CreateWorld(); glPopMatrix();/由于最后绘制的是在正常光照下地板的反光效果，所以应先恢复光照，地板采取正常法向 glLightfv(

44、GL_LIGHT0, GL_POSITION, position0); /绘制一个半透明的地板 glEnable(GL_BLEND); glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);glDepthMask(GL_FALSE);/关闭深度缓存写，保证混合效果 CreateGround();glDepthMask(GL_TRUE);/恢复深度缓存写 glDisable(GL_BLEND); CreateWorld(); glPopMatrix();void display()glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_B