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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.
 *
 */

/*
 *  fogindex.c
 *  This program draws 5 wireframe spheres, each at 
 *  a different z distance from the eye, in linear fog.
 */
#include <GL/glut.h>
#include <math.h>
#include <stdlib.h>
#include <stdio.h>

/*  Initialize color map and fog.  Set screen clear color
 *  to end of color ramp.
 */
#define NUMCOLORS 32
#define RAMPSTART 16

static void init(void)
{
   int i;

   glEnable(GL_DEPTH_TEST);

   for (i = 0; i < NUMCOLORS; i++) {
      GLfloat shade;
      shade = (GLfloat) (NUMCOLORS-i)/(GLfloat) NUMCOLORS;
      glutSetColor (RAMPSTART + i, shade, shade, shade);
   }
   glEnable(GL_FOG);

   glFogi (GL_FOG_MODE, GL_LINEAR);
   glFogi (GL_FOG_INDEX, NUMCOLORS);
   glFogf (GL_FOG_START, 1.0);
   glFogf (GL_FOG_END, 6.0);
   glHint (GL_FOG_HINT, GL_NICEST);
   glClearIndex((GLfloat) (NUMCOLORS+RAMPSTART-1));
}

static void renderSphere (GLfloat x, GLfloat y, GLfloat z)
{
   glPushMatrix();
   glTranslatef (x, y, z);
   glutWireSphere(0.4, 16, 16);
   glPopMatrix();
}

/*  display() draws 5 spheres at different z positions.
 */
void display(void)
{
   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
   glIndexi (RAMPSTART);

   renderSphere (-2., -0.5, -1.0);
   renderSphere (-1., -0.5, -2.0);
   renderSphere (0., -0.5, -3.0);
   renderSphere (1., -0.5, -4.0);
   renderSphere (2., -0.5, -5.0);

   glFlush();
}

void reshape(int w, int h)
{
   glViewport(0, 0, w, h);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   if (w <= h)
      glOrtho (-2.5, 2.5, -2.5*(GLfloat)h/(GLfloat)w,
         2.5*(GLfloat)h/(GLfloat)w, -10.0, 10.0);
   else
      glOrtho (-2.5*(GLfloat)w/(GLfloat)h,
         2.5*(GLfloat)w/(GLfloat)h, -2.5, 2.5, -10.0, 10.0);
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity ();
}

void keyboard(unsigned char key, int x, int y)
{

   switch (key) {
      case 27:
         exit(0);
   }
}


/*  Main Loop
 *  Open window with initial window size, title bar, 
 *  color index mode, depth buffer, and handle input events.
 */
int main(int argc, char** argv)
{
   glutInit(&argc, argv);
   glutInitDisplayMode (GLUT_SINGLE | GLUT_INDEX | GLUT_DEPTH);
   glutInitWindowSize(500, 500);
   glutCreateWindow(argv[0]);
   init();
   glutReshapeFunc (reshape);
   glutKeyboardFunc (keyboard);
   glutDisplayFunc (display);
   glutMainLoop();
   return 0;
}