[记录]使用openGL显示点云的一个程序

 #include <GL/glut.h>
 #include <stdio.h>
 #include <iostream>
 using namespace std;
 void myDisplay(void);
 //char * filename=(char *)"d:/aaacpp/点云数据转换/data/人体点云数据_out.asc";
 char * filename=NULL;

 static GLfloat xRot=0.0f;
 static GLfloat yRot=0.0f;
 int n;

 float xTmp[];
 float yTmp[];
 float zTmp[];

 void getPoint(char * filename,float * pX,float * pY,float * pZ,int & n)
 {
     FILE * fp=NULL;
     n=;
     if (fp = fopen(filename, "r"), fp == NULL)
     {
         cout << "文件打开失败，文件路径：" << filename << endl;
         exit();
     }
     while(!feof(fp))
     {
         fscanf(fp,"%f %f %f\n",&pX[n],&pY[n],&pZ[n]);
         ++n;
         //glVertex3f(x/2,y/2,z/2);
     }
 }

 void printPoint(float * pX,float * pY,float * pZ,int n)
 {
     int i=;
     float x,y,z;
     while(i<n)
     {
         x=pX[i];
         y=pY[i];
         z=pZ[i];
         glVertex4f(x,y,z,2.0);
         ++i;
     }
 }

 void Display(void)
 {
     glClear(GL_COLOR_BUFFER_BIT);
     glPushMatrix();
     glRotatef(xRot,1.0,0.0,0.0);
     glRotatef(yRot,0.0,1.0,0.0);
     glBegin(GL_POINTS);
     glColor3f(1.0,1.0,1.0);//白色
     //glVertex2f(0.0f,0.0f);
     //glVertex2f(0.5f,0.8f);

     printPoint(xTmp,yTmp,zTmp,n);
     glEnd();
     glBegin(GL_LINES);//glBegin和glEnd保证指定的这些点有效
     glColor3f(1.0,0.0,0.0);//红色
     glVertex3f(0.0,0.0,0.0);
     glVertex3f(1.0,0.0,0.0);
     glColor3f(0.0,1.0,0.0);//绿色
     glVertex3f(0.0,0.0,0.0);
     glVertex3f(0.0,1.0,0.0);
     glColor3f(0.0,0.0,1.0);//蓝色
     glVertex3f(0.0,0.0,0.0);
     glVertex3f(0.0,0.0,1.0);
     glEnd();
     glFlush();//保证前面的命令立即执行
     glPopMatrix();
     glutSwapBuffers();
 }

 void rDisplay()
 {
     static int i=;
     ++i;
     glPushMatrix();
     glRotatef(0.1*i,1.0f,0.0f,0.0f);
     //draw();
     glPopMatrix();
     glFlush();
     //glutSwapBuffers();
 }

 void SpecialKeys(int key,int x,int y)
 {
     float span=5.0;
     switch(key)
     {
         case GLUT_KEY_UP:
             xRot-=span;
             break;
         case GLUT_KEY_DOWN:
             xRot+=span;
             break;
         case GLUT_KEY_LEFT:
             yRot-=span;
             break;
         case GLUT_KEY_RIGHT:
             yRot+=span;
             break;
         default:
             break;
     }
     xRot=(xRot>360.0)?(xRot-360.0):xRot;
     xRot=(xRot<0.0)?(xRot+360.0):xRot;
     yRot=(yRot>360.0)?(yRot-360.0):yRot;
     yRot=(yRot<0.0)?(yRot+360.0):yRot;
     glutPostRedisplay();
 }

 int main(int argc,char* argv[])
 {
     glutInit(&argc,argv);
     filename=(argc==)?argv[]:NULL;
     getPoint(filename,xTmp,yTmp,zTmp,n);
     glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
     glutInitWindowPosition(,);
     glutInitWindowSize(,);
     glutCreateWindow("Three Window");//直到glutMainLoop才显示窗口
     glPointSize(1.0);
     glLineWidth(1.0);
     glClearColor(0.0,0.0,0.0,0.0);
     glClear(GL_COLOR_BUFFER_BIT);
     glFlush();
     glutSwapBuffers();
     glViewport(, , , );
     glMatrixMode(GL_MODELVIEW);//设置当前操作的矩阵为模型视图矩阵
     //glLoadIdentity();//使当前绘图坐标系与世界坐标系重合
     //glTranslatef(0.5,0.5,0.5);//使绘图坐标系相对世界坐标系沿xyz移动
     glutDisplayFunc(&Display);
     glutSpecialFunc(&SpecialKeys);
     //glutIdleFunc(&rDisplay);
     glutMainLoop();
     return ;
 }

 void myDisplay(void)
 {
     static int i=;
     ++i;
     glEnable(GL_DEPTH_TEST);
     glColor3f(1.0f,,);
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
     glMatrixMode(GL_PROJECTION);
     glLoadIdentity();
     //gluPerspective(75,1,1,40000000);
     glMatrixMode(GL_MODELVIEW);
     glLoadIdentity();
         glRotatef(0.01*i,1.0f,0.0f,0.0f);
     //gluLookAt(0,-20000000,-20000000,0,0,0,0,0,1);
     glPolygonMode(GL_FRONT, GL_FILL); // 设置正面为填充模式
     glPolygonMode(GL_BACK, GL_LINE);  // 设置反面为线形模式
     glFrontFace(GL_CCW);              // 设置逆时针方向为正面
     glBegin(GL_POLYGON);              // 按逆时针绘制一个正方形，在左下方
         glVertex2f(-0.5f, -0.5f);
         glVertex2f(0.0f, -0.5f);
         glVertex2f(0.0f, 0.0f);
         glVertex2f(-0.5f, 0.0f);
     glEnd();
     glBegin(GL_POLYGON);              // 按顺时针绘制一个正方形，在右上方
         glVertex2f(0.0f, 0.0f);
         glVertex2f(0.0f, 0.5f);
         glVertex2f(0.5f, 0.5f);
         glVertex2f(0.5f, 0.0f);
     glEnd();

     glFlush();
     glutSwapBuffers();
 }