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Loading .obj file in OpenGL

Jayhawker07 (33)
Ok so I have made a basic parser and loader for a 3d .obj file made in Blender. I know that the code isn't great, I made this pretty quickly and it certainly could be more efficient. However my problem is that OpenGL lights it as if it were all one polygon, and it makes it look artificial and it is hard to make out details. How could I make it so OpenGL recognises the vertices as multiple polygons so it can properly light them? Thanks.

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//main.cpp

#include <GL/freeglut.h>
#include <GL/gl.h>
#include <stdio.h>

#include "reader.h"

Reader obj;

float angle;

void init(int argc, char **argv)
{
    glutInit(&argc, argv);
    glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGBA | GLUT_DEPTH);
    glutInitWindowSize(800, 600);
    glutInitWindowPosition(150, 150);
    glutCreateWindow("Generic RPG 3D");

    AllocConsole();
    freopen( "CON", "wt", stdout );
    freopen( "CON", "wt", stderr );

    obj.load("cube.obj");

    glEnable (GL_DEPTH_TEST);
    glEnable (GL_LIGHTING);
    glEnable (GL_LIGHT0);
}

void display(void)
{
    glClearColor(1.0f, 0.0f, 0.0f, 1.0f);
    glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glLoadIdentity();

    glTranslatef(0.0f, -2.75f, -5.0f);
    obj.draw("cube.obj");

    glutSwapBuffers();
    angle += .1f;
}

void reshape( int width, int height )
{
    glViewport(0, 0, (GLsizei)width, (GLsizei)height );
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(60, (GLfloat)width / (GLfloat)height, 1.0, 100.0);
    glMatrixMode(GL_MODELVIEW);
}

int main(int argc, char **argv)
{

    init(argc, argv);

    glutDisplayFunc(display);
    glutReshapeFunc(reshape);
    glutIdleFunc(display);
    glutMainLoop();

    return 0;
}



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//reader.cpp

#include <GL/freeglut.h>
#include <fstream>

#include "reader.h"

using namespace std;

Reader::Reader()
{
    for(int i = 0; i < 256; i++ ) {
        vertex[i].x = 0;
        vertex[i].y = 0;
        vertex[i].z = 0;
    }
}

Reader::~Reader()
{

}

void Reader::load(char* filename)
{
    ifstream file;
    file.open(filename);

    string str;

    while(!file.eof()) //while we are still in the file
    {
        getline(file,str); //move one line down
        if(str[0] == 'v') break; //if we have a vertex line, stop
    }

    int v = 0;

    while(str[0] == 'v') {

        int i = 0;

        while(true)
        {
            while(str[i] == ' ' )
            {
                i++; //move a space over
            }
            i++;
            i++;
            int j = i, k = i;
            while(str[i] != ' ') {  
                i++;
                k = i;
            }
            vertex[v].x = atof(str.substr(j, k-j).c_str());

            //moving on to the y coord

            while(str[i] == ' ' ) {
                i++;
            }

            int q = i, w = i;
            while(str[i] != ' ' ) {
                i++;
                w = i;
            }
            vertex[v].y = atof(str.substr(q, w-q).c_str());

            while(str[i] == ' ' ) {
                i++;
            }

            int a = i, s = i;
            while(str[i] != ' ' ) {
                i++;
                s = i;
            }
            vertex[v].z = atof(str.substr(a, s-a).c_str());

            break;
        }
        v++; 
        getline(file, str);  
    }
}

void Reader::draw(char *filename)
{
    ifstream file;
    file.open(filename);

    string str;

    while(true)
    {
        getline(file, str);
        if(str[0] == 'f' ) {
            break;
        }
    }

    int i = 0;

    while(str[0] == 'f')
    {

        while(str[i] == 'f') i++;
        while(str[i] == ' ') i++;
        int j = i, k = i;

        while(str[i] != ' ') {  
            i++;
            k = i;
        }

        int one = atof(str.substr(j, k - j).c_str());

        i +=1;

        j = i;
        k = i;

        while(str[i] != ' ') { 
            i++;
            k = i;
        }

        int two = atof(str.substr(j, k - j).c_str());

        i+=1;

        j = i;
        k = i;

        while(str[i] != ' ') {  
            i++;
            k = i;
        }

        int three = atof(str.substr(j, k - j).c_str());

        i+=1;

        j = i;
        k = i;

        while(str[i] != ' ') {  
            i++;
            k = i;
        }

        int four = atof(str.substr(j, k - j).c_str());

        glBegin(GL_POLYGON);
        glVertex3d(vertex[one - 1].x, vertex[one - 1].y, vertex[one - 1].z);
        glVertex3d(vertex[two - 1].x, vertex[two - 1].y, vertex[two - 1].z);
        glVertex3d(vertex[three - 1].x, vertex[three - 1].y, vertex[three - 1].z);
        glVertex3d(vertex[four - 1].x, vertex[four - 1].y, vertex[four - 1].z);
        glEnd();

        getline(file, str);
        i = 0;
    }

}



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//reader.h

#ifndef READER_H
#define READER_H

#define MAX_VERT 100000

struct Vertex {

    float x;
    float y;
    float z;

};


class Reader {
    private:
        Vertex vertex[256];

    public:
        Reader();
        ~Reader();

        void load(char* filename);
        void draw(char* filename);


};

#endif

Jayhawker07 (33)
Here is the .obj file that I am using. Sorry about not commenting the code above, it was before but I had to take the comments out in order for it all to fit.


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//cube.obj

# Blender v2.64 (sub 0) OBJ File: ''
# www.blender.org
mtllib cube.mtl
o Grid_Grid.001
v 0.518272 1.131488 1.935897
v 0.384532 1.087422 1.877534
v 0.194592 1.131488 1.935897
v 0.055283 1.173685 2.018032
v -0.129088 1.131488 1.935897
v -0.290928 1.131488 1.935897
v -0.419401 1.162998 2.006013
v -0.614609 1.131488 1.935897
v -0.776449 1.131488 1.935897
v -0.938289 1.131488 1.935897
v 0.518272 1.131488 1.774056
v 0.356432 1.131488 1.774056
v 0.194592 1.131488 1.774056
v 0.032752 1.131488 1.774056
v -0.133140 1.187131 1.864440
v -0.283516 1.097859 1.722068
v -0.448529 1.120777 1.758496
v -0.614609 1.131488 1.774056
v -0.666732 1.323140 1.818890
v -0.938289 1.131488 1.774056
v 0.514737 1.219958 1.757466
v 0.341049 1.157256 1.646901
v 0.103853 1.259472 1.776878
v 0.032752 1.131488 1.612216
v -0.129088 1.131488 1.612216
v -0.290928 1.131488 1.612216
v -0.452769 1.131488 1.612216
v -0.614609 1.131488 1.612216
v -0.727726 1.183092 1.605145
v -0.906684 1.096586 1.570953
v 0.499078 1.181330 1.523074
v 0.333517 1.194935 1.543723
v 0.118743 1.190631 1.508461
v 0.032752 1.131488 1.450376
v -0.218255 1.271678 1.365329
v -0.395605 1.329857 1.326677
v -0.452769 1.131488 1.450376
v -0.615633 1.249461 1.546403
v -0.776449 1.131488 1.450376
v -0.970506 1.162958 1.485606
v 0.508798 1.195456 1.389886
v 0.356432 1.131488 1.288536
v 0.247507 1.102528 1.268469
v 0.032752 1.131488 1.288536
v -0.018010 1.286906 1.119142
v -0.442831 1.411379 1.114659
v -0.486016 1.159259 1.341606
v -0.614609 1.131488 1.288536
v -0.691108 1.214893 1.270527
v -0.938289 1.131488 1.288536
v 0.518272 1.131488 1.126696
v 0.343100 1.171472 1.186112
v 0.169748 1.177407 1.189869
v 0.032752 1.131488 1.126696
v -0.159585 1.154632 1.171387
v -0.313079 1.177570 1.209258
v -0.444593 1.193086 1.192916
v -0.531590 1.204827 1.102899
v -0.714528 1.170166 1.223892
v -0.909191 1.187848 1.143041
v 0.518272 1.131488 0.964856
v 0.356432 1.131488 0.964856
v 0.212689 1.112853 0.943475
v -0.002549 1.196509 1.082023
v -0.129088 1.131488 0.964856
v -0.170148 1.195811 0.896109
v -0.420159 1.077837 0.892947
v -0.614609 1.131488 0.964856
v -0.776449 1.131488 0.964856
v -0.938289 1.131488 0.964856
v 0.493473 1.178760 0.868463
v 0.356432 1.131488 0.803016
v 0.206293 1.161256 0.815311
v 0.032752 1.131488 0.803016
v -0.129088 1.131488 0.803016
v -0.290928 1.131488 0.803016
v -0.391409 1.198935 0.796091
v -0.614609 1.131488 0.803016
v -0.773828 1.202375 0.857486
v -1.008615 1.228812 0.852519
v 0.518272 1.131488 0.641176
v 0.356432 1.131488 0.641176
v 0.308955 1.244107 0.617727
v 0.032752 1.131488 0.641176
v -0.134324 1.238977 0.704124
v -0.290928 1.131488 0.641176
v -0.462566 1.216063 0.719063
v -0.614609 1.131488 0.641176
v -0.735736 1.090856 0.633541
v -0.938289 1.131488 0.641176
v 0.518272 1.131488 0.479336
v 0.356432 1.131488 0.479336
v 0.194592 1.131488 0.479336
v 0.032752 1.131488 0.479336
v -0.129088 1.131488 0.479336
v -0.290928 1.131488 0.479336
v -0.452769 1.131488 0.479336
v -0.614609 1.131488 0.479336
v -0.776449 1.131488 0.479336
v -0.992984 1.239501 0.561084
usemtl 
s off
f 19 20 10 9
f 14 15 5 4
f 15 16 6 5
f 16 17 7 6
f 2 1 11 12
f 17 18 8 7
f 12 13 3 2
f 18 19 9 8
f 13 14 4 3
f 25 26 16 15
f 26 27 17 16
f 21 22 12 11
f 27 28 18 17
f 22 23 13 12
f 28 29 19 18
f 23 24 14 13
f 29 30 20 19
f 24 25 15 14
f 37 38 28 27
f 32 33 23 22
f 38 39 29 28
f 33 34 24 23
f 39 40 30 29
f 34 35 25 24
f 35 36 26 25
f 36 37 27 26
f 31 32 22 21
f 44 45 35 34
f 45 46 36 35
f 46 47 37 36
f 41 42 32 31
f 47 48 38 37
f 42 43 33 32
f 48 49 39 38
f 43 44 34 33
f 49 50 40 39
f 56 57 47 46
f 51 52 42 41
f 57 58 48 47
f 52 53 43 42
f 58 59 49 48
f 53 54 44 43
f 59 60 50 49
f 54 55 45 44
f 55 56 46 45
f 63 64 54 53
f 69 70 60 59
f 64 65 55 54
f 65 66 56 55
f 66 67 57 56
f 61 62 52 51
f 67 68 58 57
f 62 63 53 52
f 68 69 59 58
f 75 76 66 65
f 76 77 67 66
f 71 72 62 61
f 77 78 68 67
f 72 73 63 62
f 78 79 69 68
f 73 74 64 63
f 79 80 70 69
f 74 75 65 64
f 82 83 73 72
f 88 89 79 78
f 83 84 74 73
f 89 90 80 79
f 84 85 75 74
f 85 86 76 75
f 86 87 77 76
f 81 82 72 71
f 87 88 78 77
f 94 95 85 84
f 95 96 86 85
f 96 97 87 86
f 91 92 82 81
f 97 98 88 87
f 92 93 83 82
f 98 99 89 88
f 93 94 84 83
f 99 100 90 89
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