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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.
 *
 */

/*
 *  tess.c
 *  This program demonstrates polygon tessellation.
 *  Two tesselated objects are drawn.  The first is a
 *  rectangle with a triangular hole.  The second is a
 *  smooth shaded, self-intersecting star.
 *
 *  Note the exterior rectangle is drawn with its vertices
 *  in counter-clockwise order, but its interior clockwise.
 *  Note the combineCallback is needed for the self-intersecting
 *  star.  Also note that removing the TessProperty for the 
 *  star will make the interior unshaded (WINDING_ODD).
 */
#include <GL/glut.h>
#include <stdlib.h>
#include <stdio.h>

#ifndef CALLBACK 
#define CALLBACK
#endif

GLuint startList;

void display (void) {
   glClear(GL_COLOR_BUFFER_BIT);
   glColor3f(1.0, 1.0, 1.0);
   glCallList(startList);
   glCallList(startList + 1);
   glFlush();
}

void CALLBACK beginCallback(GLenum which)
{
   glBegin(which);
}

void CALLBACK errorCallback(GLenum errorCode)
{
   const GLubyte *estring;

   estring = gluErrorString(errorCode);
   fprintf(stderr, "Tessellation Error: %s\n", estring);
   exit(0);
}

void CALLBACK endCallback(void)
{
   glEnd();
}

void CALLBACK vertexCallback(GLvoid *vertex)
{
   const GLdouble *pointer;

   pointer = (GLdouble *) vertex;
   glColor3dv(pointer+3);
   glVertex3dv(vertex);
}

/*  combineCallback is used to create a new vertex when edges
 *  intersect.  coordinate location is trivial to calculate,
 *  but weight[4] may be used to average color, normal, or texture
 *  coordinate data.  In this program, color is weighted.
 */
void CALLBACK combineCallback(GLdouble coords[3], 
                     GLdouble *vertex_data[4],
                     GLfloat weight[4], GLdouble **dataOut )
{
   GLdouble *vertex;
   int i;

   vertex = (GLdouble *) malloc(6 * sizeof(GLdouble));

   vertex[0] = coords[0];
   vertex[1] = coords[1];
   vertex[2] = coords[2];
   for (i = 3; i < 7; i++)
      vertex[i] = weight[0] * vertex_data[0][i] 
                  + weight[1] * vertex_data[1][i]
                  + weight[2] * vertex_data[2][i] 
                  + weight[3] * vertex_data[3][i];
   *dataOut = vertex;
}

void init (void) 
{
   GLUtesselator *tobj;
   GLdouble rect[4][3] = {50.0, 50.0, 0.0,
                          200.0, 50.0, 0.0,
                          200.0, 200.0, 0.0,
                          50.0, 200.0, 0.0};
   GLdouble tri[3][3] = {75.0, 75.0, 0.0,
                         125.0, 175.0, 0.0,
                         175.0, 75.0, 0.0};
   GLdouble star[5][6] = {250.0, 50.0, 0.0, 1.0, 0.0, 1.0,
                          325.0, 200.0, 0.0, 1.0, 1.0, 0.0,
                          400.0, 50.0, 0.0, 0.0, 1.0, 1.0,
                          250.0, 150.0, 0.0, 1.0, 0.0, 0.0,
                          400.0, 150.0, 0.0, 0.0, 1.0, 0.0};

   glClearColor(0.0, 0.0, 0.0, 0.0);

   startList = glGenLists(2);

   tobj = gluNewTess();
   gluTessCallback(tobj, GLU_TESS_VERTEX, 
                   glVertex3dv);
   gluTessCallback(tobj, GLU_TESS_BEGIN, 
                   beginCallback);
   gluTessCallback(tobj, GLU_TESS_END, 
                   endCallback);
   gluTessCallback(tobj, GLU_TESS_ERROR, 
                   errorCallback);

   /*  rectangle with triangular hole inside  */
   glNewList(startList, GL_COMPILE);
   glShadeModel(GL_FLAT);    
   gluTessBeginPolygon(tobj, NULL);
      gluTessBeginContour(tobj);
         gluTessVertex(tobj, rect[0], rect[0]);
         gluTessVertex(tobj, rect[1], rect[1]);
         gluTessVertex(tobj, rect[2], rect[2]);
         gluTessVertex(tobj, rect[3], rect[3]);
      gluTessEndContour(tobj);
      gluTessBeginContour(tobj);
         gluTessVertex(tobj, tri[0], tri[0]);
         gluTessVertex(tobj, tri[1], tri[1]);
         gluTessVertex(tobj, tri[2], tri[2]);
      gluTessEndContour(tobj);
   gluTessEndPolygon(tobj);
   glEndList();

   gluTessCallback(tobj, GLU_TESS_VERTEX, 
                   vertexCallback);
   gluTessCallback(tobj, GLU_TESS_BEGIN, 
                   beginCallback);
   gluTessCallback(tobj, GLU_TESS_END, 
                   endCallback);
   gluTessCallback(tobj, GLU_TESS_ERROR, 
                   errorCallback);
   gluTessCallback(tobj, GLU_TESS_COMBINE, 
                   combineCallback);

   /*  smooth shaded, self-intersecting star  */
   glNewList(startList + 1, GL_COMPILE);
   glShadeModel(GL_SMOOTH);    
   gluTessProperty(tobj, GLU_TESS_WINDING_RULE,
                   GLU_TESS_WINDING_POSITIVE);
   gluTessBeginPolygon(tobj, NULL);
      gluTessBeginContour(tobj);
         gluTessVertex(tobj, star[0], star[0]);
         gluTessVertex(tobj, star[1], star[1]);
         gluTessVertex(tobj, star[2], star[2]);
         gluTessVertex(tobj, star[3], star[3]);
         gluTessVertex(tobj, star[4], star[4]);
      gluTessEndContour(tobj);
   gluTessEndPolygon(tobj);
   glEndList();
   gluDeleteTess(tobj);
}

void reshape (int w, int h)
{
   glViewport(0, 0, (GLsizei) w, (GLsizei) h);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   gluOrtho2D(0.0, (GLdouble) w, 0.0, (GLdouble) h);
}

void keyboard(unsigned char key, int x, int y)
{
   switch (key) {
      case 27:
         exit(0);
         break;
   }
}

int main(int argc, char** argv)
{
   glutInit(&argc, argv);
   glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
   glutInitWindowSize(500, 500);
   glutCreateWindow(argv[0]);
   init();
   glutDisplayFunc(display);
   glutReshapeFunc(reshape);
   glutKeyboardFunc(keyboard);
   glutMainLoop();
   return 0;  
}