c++ 3d game test

#include <glut.h>
#include <vector>
#include <conio.h>
#include <cmath>

#define RANGE 0

using namespace std;

class Star
{
public:
    float x, y, z;
};

vector<Star> starList;

void display()
{
    glClear(GL_COLOR_BUFFER_BIT);

    for (vector<Star>::iterator i = starList.begin(); i != starList.end(); ++i)
    {
        const float L = 70 / abs(i->z - (70 + 50));
        glPointSize(1.0f + 1.0f - (50 - i->z) / 550.0f);
        glColor3f(L, L, L);
        glBegin(GL_POINTS);
        glVertex3f(i->x, i->y, i->z);
        glEnd();
    }

    glutSwapBuffers();
}

void timer(int = 0)
{
    glutPostRedisplay();
    glutTimerFunc(1, timer, 0);
}

void Keyboard(unsigned char key, int x, int y)
{
    if(key == 'w')
    {
        for (vector<Star>::iterator i = starList.begin(); i != starList.end(); ++i)
        {
            i->z += 10;
        }
    }

    if(key == 's')
    {
        for (vector<Star>::iterator i = starList.begin(); i != starList.end(); ++i)
        {
            i->z -= 10;
        }
    }

    if(key == 'd')
    {
        for (vector<Star>::iterator i = starList.begin(); i != starList.end(); ++i)
        {
            i->x -= 10;
        }
    }

    if(key == 'a')
    {
        for (vector<Star>::iterator i = starList.begin(); i != starList.end(); ++i)
        {
            i->x += 10;
        }
    }
}

int main(int argc, char **argv)
{
    for (int i = 0; i < 10000; i++)
    {
        Star star = {
            1.0f * (rand() % (2 * RANGE) - RANGE),
            1.0f * (rand() % (2 * RANGE) - RANGE),
            1.0f * (rand() % 2000)
        };

        starList.push_back(star);
    }

    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);
    glutInitWindowSize(852, 480);
    glutInitWindowPosition(0, 86);
    glutCreateWindow("Stars");
    glClearColor(0, 0, 0, 1.0);

    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(45, 1, 0, 100);
    glutDisplayFunc(display);
    glutKeyboardFunc(Keyboard);
    timer();
    glutMainLoop();
}