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

/*
 * material.c
 * This program demonstrates the use of the GL lighting model.
 * Several objects are drawn using different material characteristics.
 * A single light source illuminates the objects.
 */
#include "glos.h"

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

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

/*  Initialize z-buffer, projection matrix, light source,
 *  and lighting model.  Do not specify a material property here.
 */
void myinit(void)
{
    GLfloat ambient[] = { 0.0, 0.0, 0.0, 1.0 };
    GLfloat diffuse[] = { 1.0, 1.0, 1.0, 1.0 };
    GLfloat specular[] = { 1.0, 1.0, 1.0, 1.0 };
    GLfloat position[] = { 0.0, 3.0, 2.0, 0.0 };
    GLfloat lmodel_ambient[] = { 0.4, 0.4, 0.4, 1.0 };
    GLfloat local_view[] = { 0.0 };

    glEnable(GL_DEPTH_TEST);
    glDepthFunc(GL_LESS);

    glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);
    glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse);
    glLightfv(GL_LIGHT0, GL_POSITION, position);
    glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);
    glLightModelfv(GL_LIGHT_MODEL_LOCAL_VIEWER, local_view);

    glEnable(GL_LIGHTING);
    glEnable(GL_LIGHT0);

    glClearColor(0.0, 0.1, 0.1, 0.0);
}

/*  Draw twelve spheres in 3 rows with 4 columns.  
 *  The spheres in the first row have materials with no ambient reflection.
 *  The second row has materials with significant ambient reflection.
 *  The third row has materials with colored ambient reflection.
 *
 *  The first column has materials with blue, diffuse reflection only.
 *  The second column has blue diffuse reflection, as well as specular
 *  reflection with a low shininess exponent.
 *  The third column has blue diffuse reflection, as well as specular
 *  reflection with a high shininess exponent (a more concentrated highlight).
 *  The fourth column has materials which also include an emissive component.
 *
 *  glTranslatef() is used to move spheres to their appropriate locations.
 */

void CALLBACK display(void)
{
    GLfloat no_mat[] = { 0.0, 0.0, 0.0, 1.0 };
    GLfloat mat_ambient[] = { 0.7, 0.7, 0.7, 1.0 };
    GLfloat mat_ambient_color[] = { 0.8, 0.8, 0.2, 1.0 };
    GLfloat mat_diffuse[] = { 0.1, 0.5, 0.8, 1.0 };
    GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };
    GLfloat no_shininess[] = { 0.0 };
    GLfloat low_shininess[] = { 5.0 };
    GLfloat high_shininess[] = { 100.0 };
    GLfloat mat_emission[] = {0.3, 0.2, 0.2, 0.0};

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

/*  draw sphere in first row, first column
 *  diffuse reflection only; no ambient or specular  
 */
    glPushMatrix();
    glTranslatef (-3.75, 3.0, 0.0);
    glMaterialfv(GL_FRONT, GL_AMBIENT, no_mat);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR, no_mat);
    glMaterialfv(GL_FRONT, GL_SHININESS, no_shininess);
    glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);
    auxSolidSphere(1.0);
    glPopMatrix();

/*  draw sphere in first row, second column
 *  diffuse and specular reflection; low shininess; no ambient
 */
    glPushMatrix();
    glTranslatef (-1.25, 3.0, 0.0);
    glMaterialfv(GL_FRONT, GL_AMBIENT, no_mat);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
    glMaterialfv(GL_FRONT, GL_SHININESS, low_shininess);
    glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);
    auxSolidSphere(1.0);
    glPopMatrix();

/*  draw sphere in first row, third column
 *  diffuse and specular reflection; high shininess; no ambient
 */
    glPushMatrix();
    glTranslatef (1.25, 3.0, 0.0);
    glMaterialfv(GL_FRONT, GL_AMBIENT, no_mat);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
    glMaterialfv(GL_FRONT, GL_SHININESS, high_shininess);
    glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);
    auxSolidSphere(1.0);
    glPopMatrix();

/*  draw sphere in first row, fourth column
 *  diffuse reflection; emission; no ambient or specular reflection
 */
    glPushMatrix();
    glTranslatef (3.75, 3.0, 0.0);
    glMaterialfv(GL_FRONT, GL_AMBIENT, no_mat);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR, no_mat);
    glMaterialfv(GL_FRONT, GL_SHININESS, no_shininess);
    glMaterialfv(GL_FRONT, GL_EMISSION, mat_emission);
    auxSolidSphere(1.0);
    glPopMatrix();

/*  draw sphere in second row, first column
 *  ambient and diffuse reflection; no specular  
 */
    glPushMatrix();
    glTranslatef (-3.75, 0.0, 0.0);
    glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR, no_mat);
    glMaterialfv(GL_FRONT, GL_SHININESS, no_shininess);
    glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);
    auxSolidSphere(1.0);
    glPopMatrix();

/*  draw sphere in second row, second column
 *  ambient, diffuse and specular reflection; low shininess
 */
    glPushMatrix();
    glTranslatef (-1.25, 0.0, 0.0);
    glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
    glMaterialfv(GL_FRONT, GL_SHININESS, low_shininess);
    glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);
    auxSolidSphere(1.0);
    glPopMatrix();

/*  draw sphere in second row, third column
 *  ambient, diffuse and specular reflection; high shininess
 */
    glPushMatrix();
    glTranslatef (1.25, 0.0, 0.0);
    glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
    glMaterialfv(GL_FRONT, GL_SHININESS, high_shininess);
    glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);
    auxSolidSphere(1.0);
    glPopMatrix();

/*  draw sphere in second row, fourth column
 *  ambient and diffuse reflection; emission; no specular
 */
    glPushMatrix();
    glTranslatef (3.75, 0.0, 0.0);
    glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR, no_mat);
    glMaterialfv(GL_FRONT, GL_SHININESS, no_shininess);
    glMaterialfv(GL_FRONT, GL_EMISSION, mat_emission);
    auxSolidSphere(1.0);
    glPopMatrix();

/*  draw sphere in third row, first column
 *  colored ambient and diffuse reflection; no specular  
 */
    glPushMatrix();
    glTranslatef (-3.75, -3.0, 0.0);
    glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient_color);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR, no_mat);
    glMaterialfv(GL_FRONT, GL_SHININESS, no_shininess);
    glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);
    auxSolidSphere(1.0);
    glPopMatrix();

/*  draw sphere in third row, second column
 *  colored ambient, diffuse and specular reflection; low shininess
 */
    glPushMatrix();
    glTranslatef (-1.25, -3.0, 0.0);
    glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient_color);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
    glMaterialfv(GL_FRONT, GL_SHININESS, low_shininess);
    glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);
    auxSolidSphere(1.0);
    glPopMatrix();

/*  draw sphere in third row, third column
 *  colored ambient, diffuse and specular reflection; high shininess
 */
    glPushMatrix();
    glTranslatef (1.25, -3.0, 0.0);
    glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient_color);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
    glMaterialfv(GL_FRONT, GL_SHININESS, high_shininess);
    glMaterialfv(GL_FRONT, GL_EMISSION, no_mat);
    auxSolidSphere(1.0);
    glPopMatrix();

/*  draw sphere in third row, fourth column
 *  colored ambient and diffuse reflection; emission; no specular
 */
    glPushMatrix();
    glTranslatef (3.75, -3.0, 0.0);
    glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient_color);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR, no_mat);
    glMaterialfv(GL_FRONT, GL_SHININESS, no_shininess);
    glMaterialfv(GL_FRONT, GL_EMISSION, mat_emission);
    auxSolidSphere(1.0);
    glPopMatrix();

    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 * 2))
    glOrtho (-6.0, 6.0, -3.0*((GLfloat)h*2)/(GLfloat)w, 
        3.0*((GLfloat)h*2)/(GLfloat)w, -10.0, 10.0);
    else
    glOrtho (-6.0*(GLfloat)w/((GLfloat)h*2), 
        6.0*(GLfloat)w/((GLfloat)h*2), -3.0, 3.0, -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_DEPTH16);
    auxInitPosition (0, 0, 600, 450);
    auxInitWindow ("Lighting");
    myinit();
    auxReshapeFunc (myReshape);
    auxMainLoop(display);
    return(0);
}
