openGL 例子:创建一个二十面体

// textures.cpp : 定义控制台应用程序的入口点。//#include "stdafx.h"//=============================================================// 包含头文件//=============================================================#include <fstream>#include <iostream>#include "glew.h" // opengl 扩展封装头文件#include "glut.h" // opengl 实用工具头文件#include "math.h"//=============================================================// 导入lib//=============================================================#pragma comment(lib, "glew32.lib")using namespace std;#define tx 0.525731112119133606#define tz 0.850650808352039932GLfloat vdata[12][3]={{-tx,0.0,tz},{tx,0.0,tz},{-tx,0.0,-tz},{tx,0.0,-tz},{0.0,tz,tx},{0.0,tz,-tx},{0.0,-tz,tx},{0.0,-tz,-tx},{tz,tx,0.0},{-tz,tx,0.0},{tz,-tx,0.0},{-tz,-tx,0.0}};GLuint tindices[20][3]={{1,4,0},{4,9,0},{4,5,9},{8,5,4},{1,8,4},{1,10,8},{10,3,8},{8,3,5},{3,2,5},{3,7,2},{3,10,7},{10,6,7},{6,11,7},{6,0,11},{6,1,0},{10,1,6},{11,0,9},{2,11,9},{5,2,9},{11,2,7}};//=============================================================// 函数声明//=============================================================void Initialize(); // 初始化应用程序void Uninitialize(); // 清理应用程序void DrawFunc(); // glut描绘回调函数void ReshapeFunc(int width, int height); // glut窗口重置回调函数void KeyboardFunc(unsigned char key, int x, int y); // glut键盘回调函数void MouseFunc(int button, int state, int x, int y);// glut鼠标按下与释放回调函数void MotionFunc(int x, int y); // glut鼠标移动回调函数void IdleFunc(); // glut空闲处理回调函数 void DrawText(const char* text, float x, float y); // 在屏幕上显示文本//=============================================================// 全局变量//=============================================================const static float EPSILON = 0.000001f;const static float PI = 3.1415926f;const static float PI_2 = 6.2831852f;// 窗口相关const static int g_WindowPosX = 240;const static int g_WindowPosY = 200;int g_WindowWidth = 512;int g_WindowHeight = 384;const char* g_WindowTitle = "OpenGL 飘飘白云(www.cnblogs.com/kesalin)";// 显示模式:双缓冲，RGBA，深度缓存const static int g_DisplayMode = (GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH); // GLUT_STENCIL GLUT_ACCUMstatic float g_fov = 15.0f;float g_rotateY = 0.0f; // 绕Y轴旋转变量float g_posX = 0.0f;int _tmain(int argc, char* argv[]){// 初始化opengl, glut, glewglutInit(&argc, argv);glutInitDisplayMode(g_DisplayMode); glewInit();// 创建windowglutInitWindowPosition(g_WindowPosX, g_WindowPosY);glutInitWindowSize(g_WindowWidth, g_WindowHeight);glutCreateWindow(g_WindowTitle); //glutFullScreen();// 初始化应用程序Initialize() ;// 设定glut回调函数glutDisplayFunc(DrawFunc);glutReshapeFunc(ReshapeFunc);glutKeyboardFunc(KeyboardFunc);glutIdleFunc(IdleFunc);// 进入glut事件处理循环glutMainLoop();// 清理应用程序Uninitialize();return 0;}void printbuffer(){int imgbuf[500][380];glReadPixels(0,0,500,380,GL_RED,GL_INT,imgbuf);ofstream otf("A.txt");for(int i=0;i<500;i++){for(int j=0;j<380;j++){otf<<imgbuf[i][j];}}otf.close();}//=============================================================// 函数定义//=============================================================// 在屏幕上显示文本，x 和 y 为屏幕坐标void DrawText(const char* text, float x, float y){// 检查OpenGL状态bool isDepthOpen = false;bool isStencilOpen = false;bool isLightOpen = false;bool isFogOpen = false; if(glIsEnabled(GL_DEPTH_TEST)) {isDepthOpen = true;glDisable(GL_DEPTH_TEST);}if(glIsEnabled(GL_STENCIL_TEST)){isStencilOpen = true;glDisable(GL_STENCIL_TEST);}if(glIsEnabled(GL_LIGHTING)) {isLightOpen = true;glDisable(GL_LIGHTING);}if(glIsEnabled(GL_FOG)){isFogOpen = true;glDisable(GL_FOG);}int font = (int)GLUT_BITMAP_8_BY_13;// 设置字体颜色glColor3f(1.0, 1.0, 0.0);/** 设置正投影*/glMatrixMode(GL_PROJECTION);// 保存当前投影矩阵glPushMatrix();glLoadIdentity();gluOrtho2D( 0, g_WindowWidth, 0, g_WindowHeight );// 反转Y轴（朝下为正方向）(与窗口坐标一致)glScalef(1, -1, 1);// 将原点移动到屏幕左上方(与窗口坐标一致)glTranslatef(0, -g_WindowHeight, 0);glMatrixMode(GL_MODELVIEW);// 保存当前模型视图矩阵glPushMatrix();glLoadIdentity();// 设置文字位置glRasterPos2f( x, y );// 依次描绘所有字符(使用显示列表)for(const char* c = text; *c != '/0'; c++){glutBitmapCharacter(GLUT_BITMAP_HELVETICA_18, *c);}// 恢复之前保存的模型视图矩阵glPopMatrix();glMatrixMode(GL_PROJECTION);// 恢复之前保存的投影矩阵glPopMatrix();// 返回模型视图矩阵状态glMatrixMode(GL_MODELVIEW);// 恢复OpenGL状态if(isDepthOpen) {glEnable(GL_DEPTH_TEST);}if(isStencilOpen){glEnable(GL_STENCIL_TEST);}if(isLightOpen) {glEnable(GL_LIGHTING);}if(isFogOpen){glEnable(GL_FOG);}}// 初始化应用程序void Initialize(){glClearColor(0.0,0.0,0.0,0.0); glShadeModel(GL_SMOOTH);GLfloat mat_specular[]={0.0,0.0,1.0,1.0};GLfloat mat_shininess[]={50.0};GLfloat light_position[]={9.0,1.0,20.0,0.0};GLfloat white_light[]={1.0,1.0,1.0,1.0};GLfloat lmodel_ambient[]={0.1,0.1,0.1,1.0};glMaterialfv(GL_FRONT,GL_SPECULAR,mat_specular);glMaterialfv(GL_FRONT,GL_SHININESS,mat_shininess);glLightfv(GL_LIGHT0,GL_POSITION,light_position);glLightfv(GL_LIGHT0,GL_DIFFUSE,white_light);glLightfv(GL_LIGHT0,GL_SPECULAR,white_light);glLightModelfv(GL_LIGHT_MODEL_AMBIENT,lmodel_ambient);glEnable(GL_LIGHTING);glEnable(GL_LIGHT0);glEnable(GL_DEPTH_TEST);glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);// 设置视口，投影信息glMatrixMode(GL_PROJECTION);glLoadIdentity();gluPerspective(g_fov, (GLfloat)g_WindowWidth/g_WindowHeight, 1.0, 30.0);}// 清理应用程序void Uninitialize(){// nothing}// 空闲处理void IdleFunc(){//g_rotateY += 0.2f;// 请求重绘glutPostRedisplay();}// 描绘函数float ya=0.0f;void wujiao(){GLfloat r=2.0f;//外侧五边形半径GLfloat r2=0.75f;//内侧五边形半径GLfloat s[15];s[0]=r*sin(2*72*PI/180);s[1]=r*cos(2*72*PI/180);s[2]=0.0f;s[3]=r*sin(4*72*PI/180);s[4]=r*cos(4*72*PI/180);s[5]=0.0f;s[6]=r2*sin(36*PI/180);s[7]=r2*cos(36*PI/180);s[8]=0.0f;glEnableClientState(GL_VERTEX_ARRAY);glVertexPointer(3,GL_FLOAT,0,s);int s1[]={0,1,2};glDrawElements(GL_POLYGON,3,GL_UNSIGNED_INT,s1);}void normalize(float v[3]){GLfloat d=sqrt(v[0]*v[0]+v[1]*v[1]+v[2]*v[2]);if(d==0.0){return;}v[0]/=d;v[1]/=d;v[2]/=d;}void normcrosspord(float v1[3],float v2[3],float out[3]){out[0]=v1[1]*v2[2]-v1[2]*v2[1];out[1]=v1[2]*v2[0]-v1[0]*v2[2];out[2]=v1[0]*v2[1]-v1[1]*v2[0];normalize(out);}void drawtriangle(float *v1,float *v2,float *v3){glBegin(GL_TRIANGLES);glNormal3fv(v1);glVertex3fv(v1);glNormal3fv(v2);glVertex3fv(v2);glNormal3fv(v3);glVertex3fv(v3);glEnd();}void subdivide(float *v1,float *v2,float *v3,long depth){GLfloat v12[3],v23[3],v31[3];if(depth==0){drawtriangle(v1,v2,v3);return;}for(int i=0;i<3;i++){v12[i]=(v1[i]+v2[i])/2.0;v23[i]=(v2[i]+v3[i])/2.0;v31[i]=(v3[i]+v1[i])/2.0;}normalize(v12);normalize(v23);normalize(v31);subdivide(v1,v12,v31,depth-1);subdivide(v2,v23,v12,depth-1);subdivide(v3,v31,v23,depth-1);subdivide(v12,v23,v31,depth-1);}void DrawFunc(){// 清屏glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);for(int i=0;i<20;i++){subdivide(&vdata[tindices[i][0]][0],&vdata[tindices[i][1]][0],&vdata[tindices[i][2]][0],3);}glutSwapBuffers() ;}// 响应窗口重置事件void ReshapeFunc(int width, int height){g_WindowWidth = width;g_WindowHeight = height;glViewport(0, 0, g_WindowWidth, g_WindowHeight);//glMatrixMode(GL_PROJECTION);glLoadIdentity();gluPerspective(g_fov, (GLfloat)g_WindowWidth/g_WindowHeight, 1.0, 30.0);//--------gluLookAt(0.0f,0.0f,10.0f,0.0f,0.0f,0.0f,0.0f,1.0f,0.0f);//--------//glMatrixMode(GL_MODELVIEW);glLoadIdentity();}// 响应按键事件void KeyboardFunc(unsigned char key, int x, int y){switch (key){case 'A':case 'a':// 向左移动g_posX -= 0.05f;if( g_posX < -4.0f ){g_posX = -4.0f;}break;case 'D':case 'd':// 向右移动g_posX += 0.05f;if( g_posX > 4.0f ){g_posX = 4.0f;}break;case 27:exit(0);break;case '+':case '=':g_fov -= 5; glMatrixMode(GL_PROJECTION);glLoadIdentity();gluPerspective(g_fov, (GLfloat)g_WindowWidth/g_WindowHeight, 1.0, 30.0);//--------gluLookAt(0.0f,0.0f,10.0f,0.0f,0.0f,0.0f,0.0f,1.0f,0.0f);//--------break;case '-':case '_':g_fov += 5; glMatrixMode(GL_PROJECTION);glLoadIdentity();gluPerspective(g_fov, (GLfloat)g_WindowWidth/g_WindowHeight, 1.0, 30.0);//--------gluLookAt(0.0f,0.0f,10.0f,0.0f,0.0f,0.0f,0.0f,1.0f,0.0f);//--------break;case 'p':case 'P':glMatrixMode(GL_PROJECTION);glPushMatrix();GLfloat p[16];glGetFloatv(GL_PROJECTION_MATRIX,p);for(int i=0;i<16;i++)printf("%f ",p[i]);glPopMatrix();break;case ',':case '<':ya+=5;break;case '.':case '>':ya-=5;break;case 'z':case 'Z':printbuffer();break;default:break;}}// 响应鼠标按下与释放事件void MouseFunc(int button, int state, int x, int y){#if 0switch( button ){case GLUT_WHEEL_UP://老版本的glut库不支持鼠标中键消息的响应,所以要将glut.lib,glut.h,glut.dll三个文件更新到新版本.break;case GLUT_WHEEL_DOWN://老版本的glut库不支持鼠标中键消息的响应,所以要将glut.lib,glut.h,glut.dll三个文件更新到新版本.break;case GLUT_LEFT_BUTTON:{if( state == GLUT_UP ){}else if( state == GLUT_DOWN ){}}break;case GLUT_RIGHT_BUTTON:{if( state == GLUT_UP ){}else if( state == GLUT_DOWN ){}}break;case GLUT_MIDDLE_BUTTON:{if( state == GLUT_UP ){}else if( state == GLUT_DOWN ){}}break;}#endif}// 响应鼠标移动事件void MotionFunc(int x, int y){// nothing} 

迭代0，1，2，3次的图像