/*
 * (c) Copyright 1993, Silicon Graphics, Inc.
 *               1993-1995 Microsoft Corporation
 *
 * ALL RIGHTS RESERVED
 *
 * Please refer to OpenGL/readme.txt for additional information
 *
 */

/*  accanti.c
 */
#include "glos.h"

#include <GL/gl.h>
#include <GL/glu.h>
#include <GL/glaux.h>
#include "jitter.h"

void myinit(void);
void CALLBACK myReshape(GLsizei w, GLsizei h);
void CALLBACK display(void);

/*  Initialize lighting and other values.
 */
void myinit(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);
    glDepthFunc(GL_LESS);
    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 ();
    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);
    auxSolidTorus (0.275, 0.85);
    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);
    auxSolidCube (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);
    auxSolidSphere (1.0);
    glPopMatrix ();

    glPushMatrix ();
    glTranslatef (0.70, -0.90, 0.25); 
    glMaterialfv(GL_FRONT, GL_DIFFUSE, octa_diffuse);
    auxSolidOctahedron (1.0);
    glPopMatrix ();

    glPopMatrix ();
}

#define ACSIZE  8

void CALLBACK 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);
        glPushMatrix ();
/*  Note that 4.5 is the distance in world space between
 *  left and right and bottom and top.
 *  This formula converts fractional pixel movement to 
 *  world coordinates.
 */
        glTranslatef (j8[jitter].x*4.5/viewport[2],
            j8[jitter].y*4.5/viewport[3], 0.0);
        displayObjects ();
        glPopMatrix ();
        glAccum(GL_ACCUM, 1.0/ACSIZE);
    }
    glAccum (GL_RETURN, 1.0);
    glFlush();
}

void CALLBACK myReshape(GLsizei w, GLsizei h)
{
    h = (h == 0) ? 1 : h;
    glViewport(0, 0, w, h);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    if (w <= h) 
    glOrtho (-2.25, 2.25, -2.25*h/w, 2.25*h/w, -10.0, 10.0);
    else 
    glOrtho (-2.25*w/h, 2.25*w/h, -2.25, 2.25, -10.0, 10.0);
    glMatrixMode(GL_MODELVIEW);
}

/*  Main Loop
 *  Open window with initial window size, title bar, 
 *  RGBA display mode, and handle input events.
 */
int main(int argc, char** argv)
{
    auxInitDisplayMode (AUX_SINGLE | AUX_RGB
            | AUX_ACCUM | AUX_DEPTH16);
    auxInitPosition (0, 0, 250, 250);
    auxInitWindow ("Jittering - Orthographic");
    myinit();
    auxReshapeFunc (myReshape);
    auxMainLoop(display);
    return(0);
}