Mouse programming in opengl

Hushh.. Finally I could get the mouse working in my opengl programs.
Here is the program which will let you use the mouse to enter the coordinates in opengl window. This is very useful template program to do various graphics assignment.

// text1.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"

#include <string.h>
#include <GL/glut.h>

float rotate =0.0;
float start = 0.0;
float z_dep = 0.0;

int poi_size = 0;
int poi_arr[100][2];
int m_x = 0;
int m_y = 0;

int rubber_band_on = 0;

int down_flag = 0;
void *font = GLUT_BITMAP_TIMES_ROMAN_24;
void *fonts[] =
{
  GLUT_BITMAP_9_BY_15,
  GLUT_BITMAP_TIMES_ROMAN_10,
  GLUT_BITMAP_TIMES_ROMAN_24
};

void selectFont(int newfont)
{
  font = fonts[newfont];
  glutPostRedisplay();
}


void selectColor(int color)
{
  switch (color) {
  case 1:
    glColor3f(0.0, 1.0, 0.0);
    break;
  case 2:
    glColor3f(1.0, 0.0, 0.0);
    break;
  case 3:
    glColor3f(1.0, 1.0, 1.0);
    break;
  }
  glutPostRedisplay();
}

void tick(void)
{
  glutPostRedisplay();
}

void output(int x, int y, char *string)
{
  int len, i;

  glRasterPos2f(x, y);
  len = (int) strlen(string);
  for (i = 0; i < len; i++) {
    glutBitmapCharacter(font, string[i]);
  }
}

void display(void)
{
    // Show the X and Y coordinate location of the mouse 
  glClear(GL_COLOR_BUFFER_BIT);
  char x_coord[10];
  sprintf(x_coord,"X:%d",m_x);
  char y_coord[10];
  sprintf(y_coord,"Y:%d",m_y);
  output(0, 24, x_coord);
  output(100, 24, y_coord);
  
  // Draw the lines created by user 
   glBegin(GL_LINE_STRIP);
   for(int i=0; i<poi_size; i++) {
      glVertex2f(poi_arr[i][0],poi_arr[i][1]);
   }
   if (rubber_band_on) {
     glVertex2f(m_x,m_y);
   }

   glEnd();

  glutSwapBuffers();
}

void handleKeypress(unsigned char key, int x, int y) {
    switch (key) {
        case 27: //Escape key
            exit(0);
    }
}

void reshape(int w, int h)
{
  glViewport(0, 0, w, h);
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  gluOrtho2D(0, w, h, 0);
  glMatrixMode(GL_MODELVIEW);
}

// the mouse callback function:
void mouse_move(int x, int y)
{
    m_x = x;
    m_y = y;
    display();
}

// the mouse callback function:
void mouse(int button, int state, int x, int y)
{
    m_x = x;
    m_y = y;

    switch (button) {
    case GLUT_RIGHT_BUTTON:
        if (state == GLUT_DOWN) {
        //    glutIdleFunc(spinDisplay);
        }
        if (state == GLUT_UP) {
            if (rubber_band_on == 0) {
              poi_size--;
            }
            rubber_band_on = 0;
            glutIdleFunc(NULL);
        }
        break;
    case GLUT_LEFT_BUTTON:
        rubber_band_on = 1;
        if (state == GLUT_DOWN) {
            down_flag = 1;
        }
        if (state == GLUT_UP) {
            if(down_flag) {
                poi_arr[poi_size][0]=x;
                poi_arr[poi_size][1]=y;
                poi_size++;
                down_flag = 0;
            }
            glutIdleFunc(NULL);
        }
        break;

    default:
        break;
    }
    display();
}

int main(int argc, char **argv)
{
  int i, msg_submenu, color_submenu;

  glutInit(&argc, argv);
  for (i = 1; i < argc; i++) {
    if (!strcmp(argv[i], "-mono")) {
      font = GLUT_BITMAP_9_BY_15;
    }
  }
  glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);
  glutInitWindowSize(1000, 800);
  glutCreateWindow("GLUT Mouse example");
  glClearColor(0.0, 0.0, 0.0, 1.0);
  
  glutDisplayFunc(display);
  glutReshapeFunc(reshape);
  glutIdleFunc(tick);
  glutKeyboardFunc(handleKeypress);
  glutMouseFunc(mouse);
  glutMotionFunc(mouse_move);
  glutPassiveMotionFunc(mouse_move);

  glutMainLoop();
  return 0;             /* ANSI C requires main to return int. */
}