nurbs.rar OpenGL 实现

#include<GL/glut.h> #include<stdlib.h> #include<stdio.h> GLfloat ctlpoints[4][4][3]; int showPoints=0; int disPolygon=0; GLUnurbsObj *theNurb; //初始化曲面控制点，控制点在x、y、z方向上范围是-3—3 void init_surface(void) { int u,v; for(u=0;u<4;u++) { for(v=0;v<4;v++) { ctlpoints[u][v][0]=3.0*((float)u-1.5); ctlpoints[u][v][1]=2.0*((float)v-1.5); if((u==1||u==2)&&(v==1||v==2)) ctlpoints[u][v][2]=3.0; else ctlpoints[u][v][2]=-1.0; } } } void init(void) { //初始化材质属性 GLfloat mat_diffuse[]={0.7,0.7,0.5,1.0}; GLfloat mat_specular[]={1.0,1.0,1.0,1.0}; GLfloat mat_shininess[]={100.0}; glClearColor(0.0,0.0,0.0,0.0); glMaterialfv(GL_FRONT,GL_DIFFUSE,mat_diffuse); glMaterialfv(GL_FRONT,GL_SPECULAR,mat_specular); glMaterialfv(GL_FRONT,GL_SHININESS,mat_shininess); glEnable(GL_LIGHTING); glEnable(GL_LIGHT0); glEnable(GL_DEPTH_TEST); glEnable(GL_AUTO_NORMAL); glEnable(GL_NORMALIZE); //初始化NURBS对象 theNurb=gluNewNurbsRenderer(); gluNurbsProperty(theNurb,GLU_SAMPLING_TOLERANCE,50.0); init_surface(); } void display(void) { int i,j; GLfloat knots[8]={0.0,0.0,0.0,0.0,1.0,1.0,1.0,1.0}; glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT); glPushMatrix(); glScalef(1.5,1.5,1.5); glTranslatef(0.0,0.0,-10.0); glRotatef(290.0,1.0,0.0,0.0); glRotatef(10.0,0.0,0.0,1.0); //定义曲面显示模式 if(disPolygon) { gluNurbsProperty(theNurb,GLU_DISPLAY_MODE,GLU_OUTLINE_POLYGON); } else { gluNurbsProperty(theNurb,GLU_DISPLAY_MODE,GLU_FILL); } //开始定义NURBS曲面 gluBeginSurface(theNurb); glColor3f(1.0,1.0,1.0); //计算曲面 gluNurbsSurface(theNurb,8,knots,8,knots,4*3,3,&ctlpoints[0][0][0],4,4,GL_MAP2_VERTEX_3); gluEndSurface(theNurb); //显示控制点 if(showPoints) { glPointSize(5.0); glDisable(GL_LIGHTING); glColor3f(1.0,0.0,0.0); glBegin(GL_POINTS); for(i=0;i<4;i++) { for(j=0;j<4;j++); { glVertex3f(ctlpoints[i][j][0],ctlpoints[i][j][1],ctlpoints[i][j][2]); } } glEnd(); glEnable(GL_LIGHTING); } glPopMatrix(); glFlush(); } void reshape(int w,int h) { glViewport(0,0,(GLsizei)w,(GLsizei)h); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(54.0,(GLdouble)w/(GLdouble)h,1.0,1000.0); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glTranslatef(0.0,0.0,-5.0); } void keyboard(unsigned char key,int x,int y) { switch(key) { case'c': case'C': showPoints=!showPoints; glutPostRedisplay(); break; case'p': case'P': disPolygon=!disPolygon; glutPostRedisplay(); break; case 27: exit(0); break; default: break; } } int main(int argc,char**argv) { glutInit(&argc,argv); glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB|GLUT_DEPTH); glutInitWindowSize(500,500); glutInitWindowPosition(100,100); glutCreateWindow("绘制NURBS曲面"); init(); glutReshapeFunc(reshape); glutDisplayFunc(display); glutKeyboardFunc(keyboard); glutMainLoop(); return 0; }