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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.
 *
 */

/*  accpersp.c
 *  Use the accumulation buffer to do full-scene antialiasing
 *  on a scene with perspective projection, using the special
 *  routines accFrustum() and accPerspective().
 */
#include <GL/glut.h>
#include <stdlib.h>
#include <math.h>
#include "jitter.h"

#ifdef WIN32
#define near zNear
#define far zFar
#endif

#define PI_ 3.14159265358979323846

/* accFrustum()
 * The first 6 arguments are identical to the glFrustum() call.
 *  
 * pixdx and pixdy are anti-alias jitter in pixels. 
 * Set both equal to 0.0 for no anti-alias jitter.
 * eyedx and eyedy are depth-of field jitter in pixels. 
 * Set both equal to 0.0 for no depth of field effects.
 *
 * focus is distance from eye to plane in focus. 
 * focus must be greater than, but not equal to 0.0.
 *
 * Note that accFrustum() calls glTranslatef().  You will 
 * probably want to insure that your ModelView matrix has been 
 * initialized to identity before calling accFrustum().
 */
void accFrustum(GLdouble left, GLdouble right, GLdouble bottom, 
   GLdouble top, GLdouble near, GLdouble far, GLdouble pixdx, 
   GLdouble pixdy, GLdouble eyedx, GLdouble eyedy, GLdouble focus)
{
   GLdouble xwsize, ywsize; 
   GLdouble dx, dy;
   GLint viewport[4];

   glGetIntegerv (GL_VIEWPORT, viewport);
	
   xwsize = right - left;
   ywsize = top - bottom;
	
   dx = -(pixdx*xwsize/(GLdouble) viewport[2] + eyedx*near/focus);
   dy = -(pixdy*ywsize/(GLdouble) viewport[3] + eyedy*near/focus);
	
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   glFrustum (left + dx, right + dx, bottom + dy, top + dy, near, far);
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity();
   glTranslatef (-eyedx, -eyedy, 0.0);
}

/* accPerspective()
 * 
 * The first 4 arguments are identical to the gluPerspective() call.
 * pixdx and pixdy are anti-alias jitter in pixels. 
 * Set both equal to 0.0 for no anti-alias jitter.
 * eyedx and eyedy are depth-of field jitter in pixels. 
 * Set both equal to 0.0 for no depth of field effects.
 *
 * focus is distance from eye to plane in focus. 
 * focus must be greater than, but not equal to 0.0.
 *
 * Note that accPerspective() calls accFrustum().
 */
void accPerspective(GLdouble fovy, GLdouble aspect, 
   GLdouble near, GLdouble far, GLdouble pixdx, GLdouble pixdy, 
   GLdouble eyedx, GLdouble eyedy, GLdouble focus)
{
   GLdouble fov2,left,right,bottom,top;

   fov2 = ((fovy*PI_) / 180.0) / 2.0;

   top = near / (cos(fov2) / sin(fov2));
   bottom = -top;

   right = top * aspect;
   left = -right;

   accFrustum (left, right, bottom, top, near, far,
               pixdx, pixdy, eyedx, eyedy, focus);
}

/*  Initialize lighting and other values.
 */
void init(void)
{
   GLfloat mat_ambient[] = { 1.0, 1.0, 1.0, 1.0 };
   GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };
   GLfloat light_position[] = { 0.0, 0.0, 10.0, 1.0 };
   GLfloat lm_ambient[] = { 0.2, 0.2, 0.2, 1.0 };

   glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);
   glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
   glMaterialf(GL_FRONT, GL_SHININESS, 50.0);
   glLightfv(GL_LIGHT0, GL_POSITION, light_position);
   glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lm_ambient);
    
   glEnable(GL_LIGHTING);
   glEnable(GL_LIGHT0);
   glEnable(GL_DEPTH_TEST);
   glShadeModel (GL_FLAT);

   glClearColor(0.0, 0.0, 0.0, 0.0);
   glClearAccum(0.0, 0.0, 0.0, 0.0);
}

void displayObjects(void) 
{
   GLfloat torus_diffuse[] = { 0.7, 0.7, 0.0, 1.0 };
   GLfloat cube_diffuse[] = { 0.0, 0.7, 0.7, 1.0 };
   GLfloat sphere_diffuse[] = { 0.7, 0.0, 0.7, 1.0 };
   GLfloat octa_diffuse[] = { 0.7, 0.4, 0.4, 1.0 };
    
   glPushMatrix ();
   glTranslatef (0.0, 0.0, -5.0); 
   glRotatef (30.0, 1.0, 0.0, 0.0);

   glPushMatrix ();
   glTranslatef (-0.80, 0.35, 0.0); 
   glRotatef (100.0, 1.0, 0.0, 0.0);
   glMaterialfv(GL_FRONT, GL_DIFFUSE, torus_diffuse);
   glutSolidTorus (0.275, 0.85, 16, 16);
   glPopMatrix ();

   glPushMatrix ();
   glTranslatef (-0.75, -0.50, 0.0); 
   glRotatef (45.0, 0.0, 0.0, 1.0);
   glRotatef (45.0, 1.0, 0.0, 0.0);
   glMaterialfv(GL_FRONT, GL_DIFFUSE, cube_diffuse);
   glutSolidCube (1.5);
   glPopMatrix ();

   glPushMatrix ();
   glTranslatef (0.75, 0.60, 0.0); 
   glRotatef (30.0, 1.0, 0.0, 0.0);
   glMaterialfv(GL_FRONT, GL_DIFFUSE, sphere_diffuse);
   glutSolidSphere (1.0, 16, 16);
   glPopMatrix ();

   glPushMatrix ();
   glTranslatef (0.70, -0.90, 0.25); 
   glMaterialfv(GL_FRONT, GL_DIFFUSE, octa_diffuse);
   glutSolidOctahedron ();
   glPopMatrix ();

   glPopMatrix ();
}

#define ACSIZE	8

void display(void)
{
   GLint viewport[4];
   int jitter;

   glGetIntegerv (GL_VIEWPORT, viewport);

   glClear(GL_ACCUM_BUFFER_BIT);
   for (jitter = 0; jitter < ACSIZE; jitter++) {
      glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
      accPerspective (50.0, 
         (GLdouble) viewport[2]/(GLdouble) viewport[3], 
         1.0, 15.0, j8[jitter].x, j8[jitter].y, 0.0, 0.0, 1.0);
      displayObjects ();
      glAccum(GL_ACCUM, 1.0/ACSIZE);
   }
   glAccum (GL_RETURN, 1.0);
   glFlush();
}

void reshape(int w, int h)
{
   glViewport(0, 0, (GLsizei) w, (GLsizei) h);
}

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

/*  Main Loop
 *  Be certain you request an accumulation buffer.
 */
int main(int argc, char** argv)
{
   glutInit(&argc, argv);
   glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB
                        | GLUT_ACCUM | GLUT_DEPTH);
   glutInitWindowSize (250, 250);
   glutInitWindowPosition (100, 100);
   glutCreateWindow (argv[0]);
   init();
   glutReshapeFunc(reshape);
   glutDisplayFunc(display);
   glutKeyboardFunc(keyboard);
   glutMainLoop();
   return 0;
}