计算机图形学实验内容.doc

计算机图形学实验肖加清 实验一 图形学实验基础1、 实验目的（1） 掌握VC+绘图的一般步骤；（2） 掌握OpenGL软件包的安装方法；（3） 掌握OpenGL绘图的一般步骤；（4） 掌握OpenGL的主要功能与基本语法。二、实验内容1、VC+绘图实验（1）实验内容：以下是绘制金刚石图案。已给出VC+参考程序，但里面有部分错误，请改正，实现以下图案。N=3 N=4N=5N=10N=30N=50(2)参考程序/自定义的一个类/此代码可以放在视图类的实现文件(.cpp) 里class CP2 public:CP2();virtual CP2();CP2(double,double);double x;double y;CP2:CP2()this-x=0.0;this-y=0.0;CP2:CP2()CP2:CP2(double x0,double y0)this-x=x0;this-y=y0;/视图类的一个成员函数，这个成员函数可以放在OnDraw函数里调用。/在视图类的头文件（.h）里定义此函数void Diamond();/在视图类的实现文件（.cpp）里实现此函数void CTestView:Diamond()CP2 *P;int N;double R;R=300;N=10; P=new CP2N;CClientDC dc(this);CRect Rect;GetClientRect(&Rect); double theta;theta=2*PI/N;for(int i=0;iN;i+)Pi.x=R*cos(i*theta);Pi.y=R*sin(i*theta);for(i=0;i=N-2;i+)for(int j=i+1;j=N-1;j+) /其中ROUND函数需要自己实现，实现四舍五入的功能。dc.MoveTo(ROUND(Pi.x+Rect.right/2),ROUND(Pi.y+Rect.bottom/2); dc.LineTo(ROUND(Pj.x+Rect.right/2),ROUND(Pj.y+Rect.bottom/2);delete P;2、OpenGL绘图（1）以下是用OpenGL绘制茶壶的代码，请在OpenGL环境下运行，分析OpenGL程序的结构#include #include #include #include /定义输出窗口的大小#define WINDOW_HEIGHT 300#define WINDOW_WIDTH 500/用户初始化函数void myninit(void);/窗口大小变化时的回调函数void CALLBACK myReshape(GLsizei w,GLsizei h);/每帧OpenGL都会调用这个函数，应该把显示代码放在这个函数中void CALLBACK display(void);int window_width=WINDOW_WIDTH;int window_height=WINDOW_HEIGHT;/视点离物体的距离float distance=3.6f;/初始化，此时为空，可以在这里进行初始化操作void myinit(void)void CALLBACK display(void)/设置清屏的颜色，并清屏和深度缓冲glClearColor(0.0f,0.0f,0.0f,0.0f);glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);/设置成模型矩阵模式glMatrixMode(GL_MODELVIEW);/载入单位化矩阵glLoadIdentity();/坐标中心向Z轴平移-distance，这样使坐标中心位于视点前方glTranslatef(0.0,0.0,-distance);/在坐标中心显示一个茶壶auxWireTeapot(1.0);/等待现有的OpenGL命令执行完成glFlush();/交换前后缓冲区auxSwapBuffers();void CALLBACK myReshape(GLsizei w,GLsizei h)if(!h) return ;/这定视区glViewport(0,0,w,h);/设定透视方式glMatrixMode(GL_PROJECTION);glLoadIdentity();gluPerspective(60.0,1.0*(GLfloat)w/(GLfloat)h,1.0,30.0);window_width=w;window_height=h;/移近移远的回调函数void CALLBACK MoveNear(void)distance-=0.3f;void CALLBACK MoveFar(void)distance +=0.3f;/主函数int main(int argc,char *argv)/初始化OpenGL的显示方式auxInitDisplayMode(AUX_DOUBLE|AUX_RGB|AUX_DEPTH16);/设定OpenGL窗口位置和大小auxInitPosition(0,0,WINDOW_WIDTH,WINDOW_HEIGHT);/打开窗口auxInitWindow(OpenGL的一个简单的例子！);/调用初始化函数myinit();/设定窗口大小变化的回调函数auxReshapeFunc(myReshape);/设定移动视点的回调函数auxKeyFunc(A,MoveNear); /按A键变大auxKeyFunc(a,MoveFar); /按a键变小/使display函数一直被调用auxIdleFunc(display);/开始OpenGL的循环auxMainLoop(display);/结束程序return (0);其运行结果如图所示：（2）OPENGL绘制矩形的简单例子参考程序：#include void Initial(void)glClearColor(1.0f, 1.0f, 1.0f, 1.0f); /设置窗口背景颜色为白色glMatrixMode(GL_PROJECTION); /设置投影参数gluOrtho2D(0.0,200.0,0.0,150.0);void Display(void)glClear(GL_COLOR_BUFFER_BIT); /用当前背景色填充窗口glColor3f(1.0f, 0.0f, 0.0f); /设置当前的绘图颜色为红色glRectf(50.0f, 100.0f, 150.0f, 50.0f); /绘制一个矩形glFlush(); /处理所有的OpenGL程序int main(int argc, char* argv)glutInit(&argc, argv);glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); /初始化窗口的显示模式glutInitWindowSize(400,300); /设置窗口的尺寸glutInitWindowPosition(100,120); /设置窗口的位置glutCreateWindow(矩形); /创建一个名为矩形的窗口glutDisplayFunc(Display); /设置当前窗口的显示回调函数Initial(); /完成窗口初始化glutMainLoop(); /启动主GLUT事件处理循环return 0;三、实验结果分析 实验二 直线生成算法与用户接口与交互式技术一、实验目的1、 掌握直线生成算法 （1） DDA算法 （2）Bresenham算法2、 掌握交互式技术 （1）鼠标 （2）键盘数字键、字母键、功能键和特殊键3、实现拾取操作二、实验内容1、以下给出了DDA算法的C+代码，请参考用Visual C+实现Bresenham算法。实现DDA画线程序实验步骤： 1 建立一个DDALine的工程文件； 2 添加ddaline()成员函数 方法：在工作区中选择CLASSVIEW类窗口，右击CDDAlineView类，选择“add member function”，定义如下的成员函数： void ddaline(CDC* pDC,int x0,int y0,int x1,int y1,COLORREF color); 3 编写自定义的成员函数ddaline()程序 void CDDALineView:ddaline(CDC* pDC, int x0, int y0, int x1, int y1, COLORREF color) int length,i; float x,y,dx,dy; length=abs(x1-x0); if (abs(y1-y0)length) length=abs(y1-y0); dx=(x1-x0)/length; dy=(y1-y0)/length; x=x0+0.5;y=y0+0.5; for (i=1;iSetPixel(int)x,(int)y,color); x=x+dx;y=y+dy; 4编写OnDraw()函数 void CDDALineView:OnDraw(CDC* pDC) CDDALineDoc* pDoc = GetDocument(); ASSERT_VALID(pDoc); / TODO: add draw code for native data here ddaline(pDC,100,100,400,100,RGB(255,0,0); ddaline(pDC,400,100,400,400,RGB(0,255,0); ddaline(pDC,400,400,100,400,RGB(0,0,255); ddaline(pDC,100,400,100,100,RGB(255,255,0); ddaline(pDC,100,100,400,400,RGB(255,0,255); ddaline(pDC,100,400,400,100,RGB(0,255,255); 5编译、调试和运行程序，查看程序结果。2、以下是利于鼠标和字母键实现用户接口与交互式技术，请参照利用特殊键实现，写出其代码。（1）OPENGL中利用鼠标实现橡皮筋技术的例子#include int iPointNum = 0; /已确定点的数目int x1=0,x2=0,y1=0,y2=0; /确定的点坐标int winWidth = 400, winHeight = 300; /窗口的宽度和高度void Initial(void)glClearColor(1.0f, 1.0f, 1.0f, 1.0f); void ChangeSize(int w, int h)winWidth = w;winHeight = h;glViewport(0, 0, w, h); /指定窗口显示区域glMatrixMode(GL_PROJECTION); /设置投影参数glLoadIdentity();gluOrtho2D(0.0,winWidth,0.0,winHeight);void Display(void)glClear(GL_COLOR_BUFFER_BIT);glColor3f(1.0f, 0.0f, 0.0f); if(iPointNum = 1)glBegin(GL_LINES); /绘制直线段glVertex2i(x1,y1);glVertex2i(x2,y2);glEnd();glutSwapBuffers(); /交换缓冲区void MousePlot(GLint button, GLint action, GLint xMouse, GLint yMouse)if(button = GLUT_LEFT_BUTTON & action = GLUT_DOWN)if(iPointNum = 0 | iPointNum = 2)iPointNum = 1;x1 = xMouse;y1 = winHeight - yMouse;else iPointNum = 2;x2 = xMouse;y2 = winHeight - yMouse;glutPostRedisplay(); /指定窗口重新绘制if(button = GLUT_RIGHT_BUTTON & action = GLUT_DOWN)iPointNum = 0;glutPostRedisplay();void PassiveMouseMove (GLint xMouse, GLint yMouse)if(iPointNum = 1)x2 = xMouse;y2 = winHeight - yMouse;glutPostRedisplay();int main(int argc, char* argv)glutInit(&argc, argv);glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB); /使用双缓存及RGB模型glutInitWindowSize(400,300); glutInitWindowPosition(100,100);glutCreateWindow(橡皮筋技术); glutDisplayFunc(Display); glutReshapeFunc(ChangeSize); /指定窗口在整形回调函数glutMouseFunc(MousePlot); /指定鼠标响应函数glutPassiveMotionFunc(PassiveMouseMove); /指定鼠标移动响应函数Initial(); glutMainLoop(); return 0;（2）OPENGL中利用键盘实现橡皮筋技术的例子#include int iPointNum = 0; /已确定点的数目int x1=0,x2=0,y1=0,y2=0; /确定的点坐标int winWidth = 400, winHeight = 300; /窗口的宽度和高度void Initial(void)glClearColor(1.0f, 1.0f, 1.0f, 1.0f); void ChangeSize(int w, int h)winWidth = w;winHeight = h;glViewport(0, 0, w, h); /指定窗口显示区域glMatrixMode(GL_PROJECTION); /设置投影参数glLoadIdentity();gluOrtho2D(0.0,winWidth,0.0,winHeight);void Display(void)glClear(GL_COLOR_BUFFER_BIT);glColor3f(1.0f, 0.0f, 0.0f); if(iPointNum = 1)glBegin(GL_LINES); /绘制直线段glVertex2i(x1,y1);glVertex2i(x2,y2);glEnd();glutSwapBuffers(); /交换缓冲区void PassiveMouseMove (GLint xMouse, GLint yMouse)if(iPointNum = 1)x2 = xMouse;y2 = winHeight - yMouse;glutPostRedisplay();void Key(unsigned char key, int x, int y)switch(key)case p:if(iPointNum = 0 | iPointNum = 2)iPointNum = 1;x1 = x;y1 = winHeight - y;elseiPointNum = 2;x2 = x;y2 = winHeight - y;glutPostRedisplay();break;default: break;int main(int argc, char* argv)glutInit(&argc, argv);glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB); /使用双缓存及RGB模型glutInitWindowSize(400,300); glutInitWindowPosition(100,100);glutCreateWindow(橡皮筋技术); glutDisplayFunc(Display); glutReshapeFunc(ChangeSize); /指定窗口在整形回调函数glutKeyboardFunc(Key); /指定键盘响应函数glutPassiveMotionFunc(PassiveMouseMove); /指定鼠标移动响应函数Initial(); glutMainLoop(); return 0;3、以下OPENGL实现拾取操作的例子，请掌握实现拾取操作的方法。#include #include stdio.hconst GLint pickSize = 32;int winWidth = 400, winHeight = 300;void Initial(void)glClearColor(1.0f, 1.0f, 1.0f, 1.0f); void DrawRect(GLenum mode)if(mode = GL_SELECT) glPushName(1); /压入堆栈glColor3f(1.0f,0.0f,0.0f);glRectf(60.0f,50.0f,150.0f,150.0f);if(mode = GL_SELECT) glPushName(2); /压入堆栈glColor3f(0.0f,1.0f,0.0f);glRectf(230.0f,50.0f,330.0f,150.0f);if(mode = GL_SELECT) glPushName(3); /压入堆栈glColor3f(0.0f,0.0f,1.0f);glRectf(140.0f,140.0f,240.0f,240.0f);void ProcessPicks(GLint nPicks, GLuint pickBuffer)GLint i;GLuint name, *ptr;printf(选中的数目为%d个n,nPicks);ptr=pickBuffer;for(i=0;inPicks; i+)name=*ptr; /选中图元在堆栈中的位置ptr+=3; /跳过名字和深度信息ptr+=name-1; /根据位置信息获得选中的图元名字if(*ptr=1) printf(你选择了红色图元n);if(*ptr=2) printf(你选择了绿色图元n);if(*ptr=3) printf(你选择了蓝色图元n);ptr+;printf(nn);void ChangeSize(int w, int h)winWidth = w;winHeight = h;glViewport(0, 0, w, h);glMatrixMode(GL_PROJECTION); glLoadIdentity();gluOrtho2D(0.0,winWidth,0.0,winHeight);void Display(void)glClear(GL_COLOR_BUFFER_BIT);DrawRect(GL_RENDER);glFlush();void MousePlot(GLint button, GLint action, GLint xMouse, GLint yMouse)GLuint pickBufferpickSize;GLint nPicks, vp4;if(button = GLUT_LEFT_BUTTON & action = GLUT_DOWN)glSelectBuffer(pickSize,pickBuffer); /设置选择缓冲区glRenderMode(GL_SELECT); /激活选择模式glInitNames(); /初始化名字堆栈glMatrixMode(GL_PROJECTION);glPushMatrix();glLoadIdentity();glGetIntegerv(GL_VIEWPORT, vp);/定义一个1010的选择区域gluPickMatrix(GLdouble(xMouse), GLdouble(vp3-yMouse),10.0,10.0,vp);gluOrtho2D(0.0,winWidth,0.0,winHeight);DrawRect(GL_SELECT);/恢复投影变换glMatrixMode(GL_PROJECTION);glPopMatrix();glFlush();/获得选择集并输出nPicks = glRenderMode(GL_RENDER);ProcessPicks(nPicks, pickBuffer);glutPostRedisplay();int main(int argc, char* argv)glutInit(&argc, argv);glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); glutInitWindowSize(400,300); glutInitWindowPosition(100,100); glutCreateWindow(拾取操作); glutDisplayFunc(Display);glutReshapeFunc(ChangeSize);glutMouseFunc(MousePlot);Initial(); glutMainLoop(); return 0;三、实验结果分析 实验三 圆和椭圆及其它基本图形的生成算法一、实验目的（1）掌握和利用VC+实现Bresenham算法；（2）掌握利用OPENGL绘制简单多面体、二次及三次曲线的方法；（3）掌握利用OPENGL层次建模的方法。二、实验内容（1）用Visual C+实现圆和椭圆的Bresenham算法；（2）利用OPENGL绘制简单多面体、二次及三次曲线；（3）利用OPENGL层次建模1、Visual C+ 实现圆的Bresenham生成算法的参考程序如下，请在MFC环境下实现程序实现步骤： （1） 建立MidPointCircle工程文件； （2） 右击CMidPointCircleView类，建立成员函数 void MidpointCircle(CDC *pDC,int x0, int y0, int r, COLORREF color) int CirPot(CDC *pDC,int x0, int y0, int x, int y, COLORREF color) (3) 编写成员函数代码，程序如下： void CMidPointCircleView:MidpointCircle(CDC *pDC,int x0, int y0, int r, COLORREF color) int x,y; float d; x=0;y=r;d=1.25-r; CirPot(pDC,x0,y0,x,y,color); while (x=y) if(dSetPixel(x0+x),(y0+y),color); pDC-SetPixel(x0+y),(y0+x),color); pDC-SetPixel(x0+y),(y0-x),color); pDC-SetPixel(x0+x),(y0-y),color); pDC-SetPixel(x0-x),(y0-y),color); pDC-SetPixel(x0-y),(y0-x),color); pDC-SetPixel(x0-y),(y0+x),color); pDC-SetPixel(x0-x),(y0+y),color); return 0; （4）编写OnDraw(CDC* pDC)函数，程序如下： void CMidPointCircleView:OnDraw(CDC* pDC) CMidPointCircleDoc* pDoc = GetDocument(); ASSERT_VALID(pDoc); / TODO: add draw code for native data here MidpointCircle(pDC,100, 100, 10, RGB(255,0,0); MidpointCircle(pDC,500, 300, 60, RGB(255,255,0); （6） 编译、运行程序，查看结果。 2、编写画椭圆法的扫描转换程序，请在MFC 环境下实现程序实现步骤： (1) 建立MidPointEllise工程文件； (2)右击CMidPointElliseView类，建立成员函数 void MidpointEllise(CDC *pDC, int x0, int y0, int a, int b, COLORREF color) (3) 编写成员函数代码，程序如下： void CMidPointEllipseView:MidpointEllise(CDC *pDC, int x0, int y0, int a, int b, COLORREF color) int x,y; float d1,d2; x=0;y=b; d1=b*b+a*a*(-b+0.25); pDC-SetPixel(x+x0,y+y0,color); while (b*b*(x+1)a*a*(y-0.5) if (d1SetPixel(x0+x,y0+y,color); pDC-SetPixel(x0+x,y0-y,color); pDC-SetPixel(x0-x,y0+y,color); pDC-SetPixel(x0-x,y0-y,color); / 上半部分 d2=(b*(x+0.5)*(b*(x+0.5)+(a*(y-1)*(a*(y-1)-(a*b)*(a*b); while (y0) if (d2SetPixel(x0+x,y0+y,color); pDC-SetPixel(x0+x,y0-y,color); pDC-SetPixel(x0-x,y0+y,color); pDC-SetPixel(x0-x,y0-y,color); /下半部分 (4) 编写OnDraw()函数 void CMidPointEllipseView:OnDraw(CDC* pDC) CMidPointEllipseDoc* pDoc = GetDocument(); ASSERT_VALID(pDoc); / TODO: add draw code for native data here MidpointEllise(pDC, 300, 200, 50, 20, RGB(255,0,0); （5） 编译、运行程序。3、用OPENGL绘制简单多面体、二次及三次曲线的例子#include static GLsizei iMode = 1;static GLfloat xRot = 0.0f; /x方向旋转参数static GLfloat yRot = 0.0f; /y方向旋转参数GLUquadricObj *obj; /二次曲面对象void Initial(void)glClearColor(1.0f, 1.0f, 1.0f, 1.0f); glColor3f(0.0f, 0.0f, 0.0f);obj = gluNewQuadric( );gluQuadricDrawStyle(obj, GLU_LINE); /以线框方式绘制二次曲面对象void ChangeSize(int w, int h)glViewport(0, 0, w, h);glMatrixMode(GL_PROJECTION);glLoadIdentity();gluOrtho2D (-1.5f, 1.5f, -1.5f, 1.5f);void Display(void)glClear(GL_COLOR_BUFFER_BIT); glMatrixMode(GL_MODELVIEW);glLoadIdentity();glRotatef(xRot, 1.0f, 0.0f, 0.0f); /旋转图形glRotatef(yRot, 0.0f, 1.0f, 0.0f); /旋转图形/指定需要绘制的图元switch(iMode)case 1:glutWireTetrahedron();break;case 2:glutSolidTetrahedron();break;case 3:glutWireOctahedron();break;case 4:glutSolidOctahedron();break;case 5:glutWireSphere(1.0f,15,15); break;case 6:glutSolidSphere(1.0f,15,15); break;case 7:glutWireTeapot(1.0f); break;case 8:glutSolidTeapot(1.0f); break;case 9:gluSphere(obj, 1.0f, 15, 15); break;case 10:gluCylinder(obj,1.0f,0.0f,1.0f,15,15);break;case 11:gluPartialDisk(obj,0.3f,0.8f,15,15,30.0f,260.0f);break;default: break;glFlush(); void ProcessMenu(int value)iMode = value; glutPostRedisplay();void SpecialKeys(int key, int x, int y)if(key = GLUT_KEY_UP)xRot-= 5.0f;if(key = GLUT_KEY_DOWN)xRot += 5.0f;if(key = GLUT_KEY_LEFT)yRot -= 5.0f;if(key = GLUT_KEY_RIGHT)yRot += 5.0f;if(xRot 356.0f)xRot = 0.0f;if(xRot 356.0f)yRot = 0.0f;if(yRot -1.0f)yRot = 355.0f;glutPostRedisplay();int main(int argc, char* argv)glutInit(&argc, argv);glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); glutInitWindowSize(400,400); glutInitWindowPosition(100,100); glutCreateWindow(OpenGL模型绘制函数示例); /创建菜单并定义菜单回调函数int nGlutPolyMenu = glutCreateMenu(ProcessMenu); glutAddMenuEntry(线框正四面体,1); /创建GLUT多面体绘制菜单glutAddMenuEntry(实体正四面体,2);glutAddMenuEntry(线框正八面体,3);glutAddMenuEntry(实体正八面体,4);int nGlutCurveMenu = glutCreateMenu(ProcessMenu); /创建GLUT曲面绘制菜单glutAddMenuEntry(线框球面,5);glutAddMenuEntry(实体球面,6);glutAddMenuEntry(线框茶壶,7);glutAddMenuEntry(实体茶壶,8);int nGluCurveMenu = glutCreateMenu(ProcessMenu); /创建GLU曲面绘制菜单glutAddMenuEntry(线框球面,9);glutAddMenuEntry(线框圆锥面,10);glutAddMenuEntry(线框圆环面,11);int nMainMenu = glutCreateMenu(ProcessMenu); /创建主菜单glutAddSubMenu(GLUT多面体, nGlutPolyMenu);glutAddSubMenu(GLUT曲面, nGlutCurveMenu);glutAddSubMenu(GLU曲面, nGluCurveMenu);glutAttachMenu(GLUT_RIGHT_BUTTON);glutDisplayFunc(Display);glutReshapeFunc(ChangeSize);glutSpecialFunc(SpecialKeys);Initial(); glutMainLoop(); return 0;4、用OPENGL实现绘制奥运五环标志#include GLuint OlympicRings;void Initial(void)glClearColor(1.0f, 1.0f, 1.0f, 1.0f); OlympicRings = glGenLists(1);glNewList(OlympicRings, GL_COMPILE);glColor3f(1.0, 1.0, 0.0);glTranslatef(-22.0, 0.0, 0.0);glutSolidTorus(0.5, 20.0, 15, 50); /绘制黄色环glColor3f(0.0, 1.0, 0.0);glTranslatef(44.0, 0.0, 0.0);glutSolidTorus(0.5, 20.0, 15, 50); /绘制绿色环glColor3f(0.0, 0.0, 0.0);glTranslatef(-22.