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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.
 *
 */

/*
 *  aapoly.c
 *  This program draws filled polygons with antialiased
 *  edges.  The special GL_SRC_ALPHA_SATURATE blending 
 *  function is used.
 *  Pressing the 't' key turns the antialiasing on and off.
 */
#include <GL/glut.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

GLboolean polySmooth = GL_TRUE;

static void init(void)
{
   glCullFace (GL_BACK);
   glEnable (GL_CULL_FACE);
   glBlendFunc (GL_SRC_ALPHA_SATURATE, GL_ONE);
   glClearColor (0.0, 0.0, 0.0, 0.0);
}

#define NFACE 6
#define NVERT 8
void drawCube(GLdouble x0, GLdouble x1, GLdouble y0, GLdouble y1,
        GLdouble z0, GLdouble z1)
{
   static GLfloat v[8][3];
   static GLfloat c[8][4] = {
      {0.0, 0.0, 0.0, 1.0}, {1.0, 0.0, 0.0, 1.0},
      {0.0, 1.0, 0.0, 1.0}, {1.0, 1.0, 0.0, 1.0},
      {0.0, 0.0, 1.0, 1.0}, {1.0, 0.0, 1.0, 1.0},
      {0.0, 1.0, 1.0, 1.0}, {1.0, 1.0, 1.0, 1.0}
   };

/*  indices of front, top, left, bottom, right, back faces  */
   static GLubyte indices[NFACE][4] = {
      {4, 5, 6, 7}, {2, 3, 7, 6}, {0, 4, 7, 3},
      {0, 1, 5, 4}, {1, 5, 6, 2}, {0, 3, 2, 1}
   };

   v[0][0] = v[3][0] = v[4][0] = v[7][0] = x0;
   v[1][0] = v[2][0] = v[5][0] = v[6][0] = x1;
   v[0][1] = v[1][1] = v[4][1] = v[5][1] = y0;
   v[2][1] = v[3][1] = v[6][1] = v[7][1] = y1;
   v[0][2] = v[1][2] = v[2][2] = v[3][2] = z0;
   v[4][2] = v[5][2] = v[6][2] = v[7][2] = z1;

#ifdef GL_VERSION_1_1
   glEnableClientState (GL_VERTEX_ARRAY);
   glEnableClientState (GL_COLOR_ARRAY);
   glVertexPointer (3, GL_FLOAT, 0, v);
   glColorPointer (4, GL_FLOAT, 0, c);
   glDrawElements (GL_QUADS, NFACE*4, GL_UNSIGNED_BYTE, indices);
   glDisableClientState (GL_VERTEX_ARRAY);
   glDisableClientState (GL_COLOR_ARRAY);
#else
   printf ("If this is GL Version 1.0, ");
   printf ("vertex arrays are not supported.\n");
   exit(1);
#endif
}

/*  Note:  polygons must be drawn from front to back
 *  for proper blending.
 */
void display(void)
{
   if (polySmooth) {
      glClear (GL_COLOR_BUFFER_BIT);
      glEnable (GL_BLEND);
      glEnable (GL_POLYGON_SMOOTH);
      glDisable (GL_DEPTH_TEST);
   }
   else { 
      glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
      glDisable (GL_BLEND);
      glDisable (GL_POLYGON_SMOOTH);
      glEnable (GL_DEPTH_TEST);
   }

   glPushMatrix ();
      glTranslatef (0.0, 0.0, -8.0);    
      glRotatef (30.0, 1.0, 0.0, 0.0);
      glRotatef (60.0, 0.0, 1.0, 0.0); 
      drawCube(-0.5, 0.5, -0.5, 0.5, -0.5, 0.5);
   glPopMatrix ();

   glFlush ();
}

void reshape(int w, int h)
{
   glViewport(0, 0, (GLsizei) w, (GLsizei) h);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   gluPerspective(30.0, (GLfloat) w/(GLfloat) h, 1.0, 20.0);
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity();
}

void keyboard(unsigned char key, int x, int y)
{
   switch (key) {
      case 't':
      case 'T':
         polySmooth = !polySmooth;
         glutPostRedisplay();
         break;
      case 27:
         exit(0);  /*  Escape key  */
         break;
      default:
         break;
   }
}

/*  Main Loop
 */
int main(int argc, char** argv)
{
   glutInit(&argc, argv);
   glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB 
                        | GLUT_ALPHA | GLUT_DEPTH);
   glutInitWindowSize(200, 200);
   glutCreateWindow(argv[0]);
   init ();
   glutReshapeFunc (reshape);
   glutKeyboardFunc (keyboard);
   glutDisplayFunc (display);
   glutMainLoop();
   return 0;
}