问题
I'm trying to display a point cloud with OpenGL
.
I have followed some tutorials and I managed to display some geometric schema but when i try to display a point cloud read from a csv file, it does not work. The reading of file work very well.
the includes
#include <iostream>
#include <fstream>
#include <string>
#include <cstdlib>
#include <stdlib.h>
#include <stdio.h>
#include <boost/tokenizer.hpp>
#include <sstream>
#include <vector>
#include <SDL/SDL.h>
#include <GL/gl.h>
#include <GL/glu.h>
#include <algorithm>
#include "Point.cpp"
#include "drawing.cpp"
using namespace std;
declarations
void draw(vector<Point> v);
int pointsNBR = 200;
char *theFileName;
main method
int main (int argc, char** argv) {
if(argv[1]){
theFileName = argv[1];
}else{
cout << "Please enter the file name !!\n";
exit(0);
}
if(argv[2]){
pointsNBR = atoi(argv[2]);
}
PCEngine(theFileName, pointsNBR);
SDL_Init(SDL_INIT_VIDEO);
atexit(SDL_Quit);
SDL_WM_SetCaption("Point Cloud", NULL);
SDL_SetVideoMode(720,640, 32, SDL_OPENGL);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(70,(double)640/480,1,1000);
bool continuer = true;
SDL_Event event;
vector<Point> v = getCloudPoint(theFileName);
draw(v);
for (;;) {
SDL_WaitEvent(&event);
switch(event.type){
case SDL_QUIT:
exit(0);
break;
}
}
}
draw method
void draw(vector<Point> v){
glPushAttrib(GL_ALL_ATTRIB_BITS);
glPushMatrix();
glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluLookAt(3,4,2,0,0,0,0,0,1);
glPointSize(2.0);
glBegin(GL_POINTS);
for (size_t n = 0; n < v.size(); n++){
glColor3ub(v[n].r, v[n].g, v[n].b);
glVertex3d(v[n].x, v[n].y, v[n].z);
}
glEnd();
glFlush();
SDL_GL_SwapBuffers();
glPopMatrix();
glPopAttrib();
}
My problem is that I haven't any display.
Can someone help me please?
回答1:
You should use the GL_MODELVIEW
to position your cloud in the scene.
In the draw method change glMatrixMode(GL_PROJECTION);
to glMatrixMode(GL_MODELVIEW);
来源:https://stackoverflow.com/questions/22264400/how-to-display-a-point-cloud-with-opengl