Bresnham line algorithm v1

#include <Windows.h>
#include <GL\glew.h>
#include <GL\freeglut.h>
#include <iostream>

using namespace std;
int x00;
int y00;
int xEnd;
int yEnd;

void init(){
    glClearColor(1.0,1.0,1.0,1.0);
    glMatrixMode( GL_PROJECTION );
    gluOrtho2D(0,500,0,500);
}

void myline()
{
    int dx = fabs(xEnd - x00), dy = fabs(yEnd - y00);
    int p = 2*dy-dx;
    int x, y;

    if(x00>xEnd){
        x=xEnd;
        y=yEnd;
        xEnd=x00;
    }
    else{
        x=x00;
        y=y00;
    }
    glBegin(GL_POINTS);
        glColor3f(0,0,0);
        glVertex2i(x,y);
    glEnd();

    while(x<xEnd){
        x++;
        if(p<0){
            p = p + 2*dy;
        }
        else{
            y++;
            p= p + 2*dy - 2*dx;
       }
        glBegin(GL_POINTS);
            glColor3f(0,0,0);
            glVertex2i(x,y);
        glEnd();

    }

}

void display()
{
    glClear(GL_COLOR_BUFFER_BIT);
    myline();
glFlush();

}

int main(int argc, char* argv[])
{
    cout<<"Enter the co ordinates for 2 points: ";
    cin>>x00>>y00>>xEnd>>yEnd;

    glutInit(&argc, argv);
    glutInitWindowSize(600,600);
    glutInitWindowPosition(10,10);
    glutInitDisplayMode(GLUT_RGB | GLUT_SINGLE | GLUT_DEPTH);
    glutCreateWindow("Bresenham's Algo");

    init();
    glutDisplayFunc(display);
    glutMainLoop();

    return 0;
}