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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.
 *
 */

/*
 * picksquare.c
 * Use of multiple names and picking are demonstrated.  
 * A 3x3 grid of squares is drawn.  When the left mouse 
 * button is pressed, all squares under the cursor position 
 * have their color changed.
 */
#include <stdlib.h>
#include <stdio.h>
#include <GL/glut.h>

int board[3][3];   /*  amount of color for each square	*/

/*  Clear color value for every square on the board   */
void init(void)
{
   int i, j;
   for (i = 0; i < 3; i++) 
      for (j = 0; j < 3; j ++)
         board[i][j] = 0;
   glClearColor (0.0, 0.0, 0.0, 0.0);
}

/*  The nine squares are drawn.  In selection mode, each 
 *  square is given two names:  one for the row and the 
 *  other for the column on the grid.  The color of each 
 *  square is determined by its position on the grid, and 
 *  the value in the board[][] array.
 */
void drawSquares(GLenum mode)
{
   GLuint i, j;
   for (i = 0; i < 3; i++) {
      if (mode == GL_SELECT)
         glLoadName (i);
      for (j = 0; j < 3; j ++) {
         if (mode == GL_SELECT)
            glPushName (j);
         glColor3f ((GLfloat) i/3.0, (GLfloat) j/3.0, 
                    (GLfloat) board[i][j]/3.0);
         glRecti (i, j, i+1, j+1);
         if (mode == GL_SELECT)
            glPopName ();
      }
   }
}

/*  processHits prints out the contents of the 
 *  selection array.
 */
void processHits (GLint hits, GLuint buffer[])
{
   unsigned int i, j;
   GLuint ii, jj, names, *ptr;

   printf ("hits = %d\n", hits);
   ptr = (GLuint *) buffer;
   for (i = 0; i < hits; i++) {	/*  for each hit  */
      names = *ptr;
      printf (" number of names for this hit = %d\n", names); ptr++;
      printf("  z1 is %g;", (float) *ptr/0x7fffffff); ptr++;
      printf(" z2 is %g\n", (float) *ptr/0x7fffffff); ptr++;
      printf ("   names are ");
      for (j = 0; j < names; j++) { /*  for each name */
         printf ("%d ", *ptr);
         if (j == 0)  /*  set row and column  */
            ii = *ptr;
         else if (j == 1)
            jj = *ptr;
         ptr++;
      }
      printf ("\n");
      board[ii][jj] = (board[ii][jj] + 1) % 3;
   }
}

/*  pickSquares() sets up selection mode, name stack, 
 *  and projection matrix for picking.  Then the 
 *  objects are drawn.
 */
#define BUFSIZE 512

void pickSquares(int button, int state, int x, int y)
{
   GLuint selectBuf[BUFSIZE];
   GLint hits;
   GLint viewport[4];

   if (button != GLUT_LEFT_BUTTON || state != GLUT_DOWN)
      return;

   glGetIntegerv (GL_VIEWPORT, viewport);

   glSelectBuffer (BUFSIZE, selectBuf);
   (void) glRenderMode (GL_SELECT);

   glInitNames();
   glPushName(0);

   glMatrixMode (GL_PROJECTION);
   glPushMatrix ();
   glLoadIdentity ();
/*  create 5x5 pixel picking region near cursor location	*/
   gluPickMatrix ((GLdouble) x, (GLdouble) (viewport[3] - y), 
                  5.0, 5.0, viewport);
   gluOrtho2D (0.0, 3.0, 0.0, 3.0);
   drawSquares (GL_SELECT);

   glMatrixMode (GL_PROJECTION);
   glPopMatrix ();
   glFlush ();

   hits = glRenderMode (GL_RENDER);
   processHits (hits, selectBuf);
   glutPostRedisplay();
} 

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

void reshape(int w, int h)
{
   glViewport(0, 0, w, h);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   gluOrtho2D (0.0, 3.0, 0.0, 3.0);
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity();
}

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

/* Main Loop */
int main(int argc, char** argv)
{
   glutInit(&argc, argv);
   glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
   glutInitWindowSize (100, 100);
   glutInitWindowPosition (100, 100);
   glutCreateWindow (argv[0]);
   init ();
   glutReshapeFunc (reshape);
   glutDisplayFunc(display); 
   glutMouseFunc (pickSquares);
   glutKeyboardFunc (keyboard);
   glutMainLoop();
   return 0; 
}