南昌大学图形学实验报告完整版.docx

1、南昌大学图形学实验报告完整版实验一一、实验项目名称 熟悉opengl环境二、实验目的 1、掌握在利用OpenGL图形库进行图形程序设计的基本方法。 2、掌握Windows环境下的消息处理方法。 3、理解OpenGL运行机制。三、实验基本原理和内容 使用opengl绘制一个图形四、主要仪器设备及耗材PC机一台，win7 VC+6.0环境五、实验步骤1、打开VC+6.02、新建工程，键入代码3、记录结果六、实验数据及处理结果7、思考讨论题或体会或对改进实验的建议 通过第一次实验体会到opengl的魅力8、参考资料:计算机图形学（第三版）Donald Hearn 电子工业出版社 九、源代码#incl

2、udeusing namespace std;#include #include const int n = 1000;const GLfloat R = 0.5f;const GLfloat Pi = 3.1415926536f;void DrawCircle() int i; GLfloat x,y; glBegin(GL_LINE_LOOP); for(i=0; in; +i) x=R*cos(2*Pi/n*i)*(1-cos(2*Pi/n*i); y=R*sin(2*Pi/n*i)*(1-cos(2*Pi/n*i); glVertex2f(y, x+0.2f); glEnd(); gl

3、Flush();void myDisplay() glClear(GL_COLOR_BUFFER_BIT); DrawCircle();void init (void) glClearColor(1.0f,1.0f, 1.0f,0.0f); glMatrixMode (GL_PROJECTION); gluOrtho2D(-400.0,400.0,-400.0,400.0); glMatrixMode(GL_MODELVIEW); int main(int argc, char *argv) glutInit(&argc, argv); glutInitDisplayMode(GLUT_SIN

4、GLE | GLUT_RGB); glutInitWindowPosition(100, 100); glutInitWindowSize(500, 500); glutCreateWindow(心形); /init(); glutDisplayFunc(myDisplay); glutMainLoop(); return 0;实验二一、实验项目名称 任意斜率直线和中点画圆二、实验目的 理解DDA直线算法和中点画圆算法三、实验基本原理和内容 四、主要仪器设备及耗材PC机一台，win7 VC+6.0环境五、实验步骤六、实验数据及处理结果7、思考讨论题或体会或对改进实验的建议画线的核心是通过算法来

5、调整直线的生成方式，这只是其中一种方式八、参考资料:计算机图形学（第三版）Donald Hearn 电子工业出版社 附源码：1：任意直线斜率#include#include#includeusing namespace std;static float m=0;float x,y;void init(void) glClearColor(1.0,1.0,1.0,0); glMatrixMode(GL_PROJECTION); gluOrtho2D(0.0,200.0,0.0,150.0);void line() glClear(GL_COLOR_BUFFER_BIT); glColor3f(1

6、.0,0.0,0.0); if(fabs(m)=0) glBegin(GL_LINES); glVertex2i(18,70); glVertex2i(300,70); glEnd(); else if(fabs(m)=1) glBegin(GL_POINTS); x=70; y=70; for(int i=0;i=1000;i+) glVertex2f(x,y); x+=0.1; y=y+m*0.1; glEnd(); else glBegin(GL_POINTS); x=70; y=70; for(int i=0;i=1000;i+) glVertex2f(x,y); y+=0.1; x=

7、x+0.1/m; glEnd(); glFlush();void main(int argc,char *argv)coutm; glutInit(&argc,argv); glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB); glutInitWindowPosition(50,100); glutInitWindowSize(400,300); glutCreateWindow(任意斜率的直线); init(); glutDisplayFunc(line); glutMainLoop();2：中点画圆#includeusing namespace std;#i

8、nclude #include const int n = 1000;const GLfloat R = 0.5f;const GLfloat Pi = 3.1415926536f;/以下为一般圆生成算法，不采纳/*void DrawCircle() int i; glBegin(GL_LINE_LOOP); for(i=0; in; +i) glVertex2f(R*cos(2*Pi/n*i), R*sin(2*Pi/n*i); glEnd(); glFlush();void myDisplay() glClear(GL_COLOR_BUFFER_BIT); DrawCircle();*/以

9、下代码为中点画圆算法class screenPtprivate:GLint x,y;public: sceenPt()x=y=0; void setCoords(GLint xcoordValue,GLint ycoordValue) x=xcoordValue; y=ycoordValue; GLint getx() constreturn x; GLint gety() constreturn y; void incrementx()x+; void decrementy()y-;void setPixel(GLint xcoord,GLint ycoord) /glClear(GL_CO

10、LOR_BUFFER_BIT); /glColor3f (1.0,0.0,0.0); glBegin(GL_POINTS); glVertex2i(xcoord,ycoord); glEnd(); /glRectf(-0.5f, -0.5f, 0.5f, 0.5f);void circleMidpoint(GLint xc,GLint yc,GLint radius) screenPt circPt; GLint p=1-radius; circPt.setCoords(0,radius); void circlePlotPoints(GLint ,GLint ,screenPt); circ

11、lePlotPoints(xc,yc,circPt); while(circPt.getx()circPt.gety() circPt.incrementx(); if(p0) p+=2*circPt.getx()+1; else circPt.decrementy(); p+=2*(circPt.getx()-circPt.gety()+1; circlePlotPoints(xc,yc,circPt); void circlePlotPoints(GLint xc,GLint yc,screenPt circPt) setPixel(xc+circPt.getx(),yc+circPt.g

12、ety();/1 setPixel(xc-circPt.getx(),yc+circPt.gety(); setPixel(xc+circPt.getx(),yc-circPt.gety(); setPixel(xc-circPt.getx(),yc-circPt.gety(); setPixel(xc+circPt.gety(),yc+circPt.getx();/5 setPixel(xc-circPt.gety(),yc+circPt.getx(); setPixel(xc+circPt.gety(),yc-circPt.getx(); setPixel(xc-circPt.gety()

13、,yc-circPt.getx();void myDisplay() glClear(GL_COLOR_BUFFER_BIT); glColor3f(1.0f,0.0f,0.0f); glViewport(0,0,400,400); circleMidpoint(0,0,360); glFlush();void init (void) glClearColor(1.0f,1.0f, 1.0f,0.0f); glMatrixMode (GL_PROJECTION); gluOrtho2D(-400.0,400.0,-400.0,400.0); glMatrixMode(GL_MODELVIEW)

14、;int main(int argc, char *argv) glutInit(&argc, argv); glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); glutInitWindowPosition(100, 100); glutInitWindowSize(500, 500); glutCreateWindow(画一个圆); init(); glutDisplayFunc(&myDisplay); glutMainLoop(); return 0;实验三一、实验项目名称直线裁剪算法二、实验目的 掌握Sutherland-Cohen 或Liang-

15、Barsky 直线裁剪算法3、实验基本原理和内容4、四、主要仪器设备及耗材PC机一台，win7 VC+6.0环境五、实验步骤六、实验数据及处理结果 7、思考讨论题或体会或对改进实验的建议剪裁的时候要注意视点的位置，以及剪裁点的设置八、参考资料:计算机图形学（第三版）Donald Hearn 电子工业出版社 附源码：/*#include class wcPt2Dprivate: GLfloat x,y;public: wcPt3D() x=0.0; y=0.0; setCoords(GLfloat xCoord,GLfloat yCoord) x=xCoord; y=yCoord; GLfloa

16、t getx() const return x; GLfloat gety() const return y; ;inline GLint round(const GLfloat a) return GLint(a+0.5);GLint clipTest(GLfloat p,GLfloat q,GLfloat *u1,GLfloat *u2) GLfloat r; GLint returnValue=true; if(p*u2) returnValue=false; else if(r*u1) *u1=r; else if(p0.0) r=q/p; if(r*u1) returnValue=f

17、alse; else if(r*u2) *u2=r; else if(q0.0) returnValue=false; return returnValue;void lineClipLiangBarsk(wcPt2D winMin,wcPt2D winMax,wcPt2D p1,wcPt2D p2) GLfloat u1=0.0,u2=1.0,dx=p2.getx()-p1.getx(),dy; if(clipTest(-dx,p1.getx()-winMin.getx(),&u1,&u2) dy=p2.gety()-p1.gety(); if(clipTest(-dy,p1.gety()-

18、winMin.gety(),&u1,&u2) if(clipTest(dy,winMax.gety()-p1.gety(),&u1,&u2) if(u20.0) p1.setCoords(p1.getx()+u1*dx,p1.gety()+u1*dy); lineBres(round(p1.getx(),round(p1.gety(),round(p2.getx(),round(p2.gety); void myDisplay(void)glClear(GL_COLOR_BUFFER_BIT); glColor3f (1.0,0.0,0.0); glBegin (GL_LINES); glVe

19、rtex2i (180,15); glVertex2i (10,145); glEnd();glRectf(-0.5f, -0.5f, 0.5f, 0.5f);glFlush(); void init (void) glClearColor(1.0 ,1.0, 1.0,0.0); glMatrixMode (GL_PROJECTION); gluOrtho2D(0.0,200.0,0.0,150.0);int main(int argc, char *argv) glutInit(&argc, argv);glutInitDisplayMode(GLUT_RGB | GLUT_SINGLE);

20、glutInitWindowPosition(50, 100);glutInitWindowSize(400,300);glutCreateWindow(OpenGL);init ();glutDisplayFunc(&myDisplay);glutMainLoop();return 0;*/*利用VC+OpenGL实现直线的编码裁剪算法，在屏幕上用一个封闭矩形裁剪任意一条直线。#include #include int flag;void setPixel(GLint x,GLint y) glBegin(GL_POINTS); glVertex2i(x, y); glEnd(); /* B

21、resenham line-drawing procedure for |m| xEnd) x = xEnd; y = yEnd; xEnd = x0; else x = x0; y = y0; setPixel (x, y);while (x xEnd) x+; if (p 0) p += twoDy; else y+; p += twoDyMinusDx; setPixel (x, y); /*/以下未变，见课本P264/*class wcPt2D public: GLfloat x, y;inline GLint round (const GLfloat a) return GLint

22、(a + 0.5); /* Define a four-bit code for each of the outside regions of a * rectangular clipping window.const GLint winLeftBitCode = 0x1;const GLint winRightBitCode = 0x2;const GLint winBottomBitCode = 0x4;const GLint winTopBitCode = 0x8;/* A bit-mask region code is also assigned to each endpoint of

23、 an input * line segment, according to its position relative to the four edges of * an input rectangular clip window. * * An endpoint with a region-code value of 0000 is inside the clipping * window, otherwise it is outside at least one clipping boundary. If * the or operation for the two endpoint c

24、odes produces a value of * false, the entire line defined by these two endpoints is saved * (accepted). If the and operation between two endpoint codes is * true, the line is completely outside the clipping window, and it is * eliminated (rejected) from further processing. */inline GLint inside (GLi

25、nt code) return GLint (!code); inline GLint reject (GLint code1, GLint code2) return GLint (code1 & code2); inline GLint accept (GLint code1, GLint code2) return GLint (!(code1 | code2); GLubyte encode (wcPt2D pt, wcPt2D winMin, wcPt2D winMax) GLubyte code = 0x00;if (pt.x winMax.x) code = code | win

26、RightBitCode; if (pt.y winMax.y) code = code | winTopBitCode; return (code);void swapPts (wcPt2D * p1, wcPt2D * p2) wcPt2D tmp;tmp = *p1; *p1 = *p2; *p2 = tmp;void swapCodes (GLubyte * c1, GLubyte * c2) GLubyte tmp;tmp = *c1; *c1 = *c2; *c2 = tmp;void lineClipCohSuth (wcPt2D winMin, wcPt2D winMax, wcPt2D p1, wcPt2D p2) GLubyte code1, code2; GLint done = false, plotLine = false;GLfloat m; while (!done) code1 = encode (p1, winMin, winMax); code2 = encode (p2, winMin, winMax); if (accept (code1, code2) done = tru