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Change license version to 1.1.

/*
 * License Applicability. Except to the extent portions of this file are
 * made subject to an alternative license as permitted in the SGI Free
 * Software License B, Version 1.1 (the "License"), the contents of this
 * file are subject only to the provisions of the License. You may not use
 * this file except in compliance with the License. You may obtain a copy
 * of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
 * Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
 * 
 * http://oss.sgi.com/projects/FreeB
 * 
 * Note that, as provided in the License, the Software is distributed on an
 * "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
 * DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
 * CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
 * PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
 * 
 * Original Code. The Original Code is: OpenGL Sample Implementation,
 * Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
 * Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
 * Copyright in any portions created by third parties is as indicated
 * elsewhere herein. All Rights Reserved.
 * 
 * Additional Notice Provisions: The application programming interfaces
 * established by SGI in conjunction with the Original Code are The
 * OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
 * April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
 * 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
 * Window System(R) (Version 1.3), released October 19, 1998. This software
 * was created using the OpenGL(R) version 1.2.1 Sample Implementation
 * published by SGI, but has not been independently verified as being
 * compliant with the OpenGL(R) version 1.2.1 Specification.
 *
 */

/*
 *  unproject.c
 *  When the left mouse button is pressed, this program 
 *  reads the mouse position and determines two 3D points 
 *  from which it was transformed.  Very little is displayed.
 */
#include <GL/glut.h>
#include <stdlib.h>
#include <stdio.h>

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

/* Change these values for a different transformation  */
void reshape(int w, int h)
{
   glViewport (0, 0, (GLsizei) w, (GLsizei) h);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   gluPerspective (45.0, (GLfloat) w/(GLfloat) h, 1.0, 100.0);
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity();
}

void mouse(int button, int state, int x, int y) 
{
   GLint viewport[4];
   GLdouble mvmatrix[16], projmatrix[16];
   GLint realy;  /*  OpenGL y coordinate position  */
   GLdouble wx, wy, wz;  /*  returned world x, y, z coords  */

   switch (button) {
      case GLUT_LEFT_BUTTON:
         if (state == GLUT_DOWN) {
            glGetIntegerv (GL_VIEWPORT, viewport);
            glGetDoublev (GL_MODELVIEW_MATRIX, mvmatrix);
            glGetDoublev (GL_PROJECTION_MATRIX, projmatrix);
/*  note viewport[3] is height of window in pixels  */
            realy = viewport[3] - (GLint) y - 1;
            printf ("Coordinates at cursor are (%4d, %4d)\n", x, realy);
            gluUnProject ((GLdouble) x, (GLdouble) realy, 0.0, 
               mvmatrix, projmatrix, viewport, &wx, &wy, &wz); 
            printf ("World coords at z=0.0 are (%f, %f, %f)\n", 
               wx, wy, wz);
            gluUnProject ((GLdouble) x, (GLdouble) realy, 1.0, 
               mvmatrix, projmatrix, viewport, &wx, &wy, &wz); 
            printf ("World coords at z=1.0 are (%f, %f, %f)\n", 
               wx, wy, wz);
         }
         break;
      case GLUT_RIGHT_BUTTON:
         if (state == GLUT_DOWN)
            exit(0);
         break;
      default:
         break;
   }
}

void keyboard(unsigned char key, int x, int y)
{
   switch (key) {
      case 27:
         exit(0);
         break;
   }
}
   
/* 
 *  Open window, register input callback functions
 */
int main(int argc, char** argv)
{
   glutInit(&argc, argv);
   glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
   glutInitWindowSize (500, 500); 
   glutInitWindowPosition (100, 100);
   glutCreateWindow (argv[0]);
   glutDisplayFunc(display); 
   glutReshapeFunc(reshape); 
   glutKeyboardFunc (keyboard);
   glutMouseFunc(mouse);
   glutMainLoop();
   return 0;
}