#
#/* Copyright (c) Mark J. Kilgard, 1994. */
#
#/*
# * (c) Copyright 1993, Silicon Graphics, Inc.
# * ALL RIGHTS RESERVED 
# * Permission to use, copy, modify, and distribute this software for 
# * any purpose and without fee is hereby granted, provided that the above
# * copyright notice appear in all copies and that both the copyright notice
# * and this permission notice appear in supporting documentation, and that 
# * the name of Silicon Graphics, Inc. not be used in advertising
# * or publicity pertaining to distribution of the software without specific,
# * written prior permission. 
# *
# * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS"
# * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,
# * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR
# * FITNESS FOR A PARTICULAR PURPOSE.  IN NO EVENT SHALL SILICON
# * GRAPHICS, INC.  BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,
# * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY
# * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,
# * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF
# * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC.  HAS BEEN
# * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON
# * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE
# * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.
# * 
# * US Government Users Restricted Rights 
# * Use, duplication, or disclosure by the Government is subject to
# * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph
# * (c)(1)(ii) of the Rights in Technical Data and Computer Software
# * clause at DFARS 252.227-7013 and/or in similar or successor
# * clauses in the FAR or the DOD or NASA FAR Supplement.
# * Unpublished-- rights reserved under the copyright laws of the
# * United States.  Contractor/manufacturer is Silicon Graphics,
# * Inc., 2011 N.  Shoreline Blvd., Mountain View, CA 94039-7311.
# *
# * OpenGL(TM) is a trademark of Silicon Graphics, Inc.
# */
#/*
# * 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.
# */

require "opengl"
require "glut"

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

    GL::Enable(GL::DEPTH_TEST);
    GL::DepthFunc(GL::LESS);

    GL::Light(GL::LIGHT0, GL::AMBIENT, ambient);
    GL::Light(GL::LIGHT0, GL::DIFFUSE, diffuse);
    GL::Light(GL::LIGHT0, GL::POSITION, position);
    GL::LightModel(GL::LIGHT_MODEL_AMBIENT, lmodel_ambient);
    GL::LightModel(GL::LIGHT_MODEL_LOCAL_VIEWER, local_view);

    GL::Enable(GL::LIGHTING);
    GL::Enable(GL::LIGHT0);

    GL::ClearColor(0.0, 0.1, 0.1, 0.0);
end

#/*  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.
# *
# *  GL::Translatef() is used to move spheres to their appropriate locations.
# */
#
display = proc {
    no_mat = [ 0.0, 0.0, 0.0, 1.0 ];
    mat_ambient = [ 0.7, 0.7, 0.7, 1.0 ];
    mat_ambient_color = [ 0.8, 0.8, 0.2, 1.0 ];
    mat_diffuse = [ 0.1, 0.5, 0.8, 1.0 ];
    mat_specular = [ 1.0, 1.0, 1.0, 1.0 ];
    no_shininess = [ 0.0 ];
    low_shininess = [ 5.0 ];
    high_shininess = [ 100.0 ];
    mat_emission = [0.3, 0.2, 0.2, 0.0];

    GL::Clear(GL::COLOR_BUFFER_BIT | GL::DEPTH_BUFFER_BIT);

#/*  draw sphere in first row, first column
# *  diffuse reflection only; no ambient or specular  
# */
    GL::PushMatrix();
    GL::Translate(-3.75, 3.0, 0.0);
    GL::Material(GL::FRONT, GL::AMBIENT, no_mat);
    GL::Material(GL::FRONT, GL::DIFFUSE, mat_diffuse);
    GL::Material(GL::FRONT, GL::SPECULAR, no_mat);
    GL::Material(GL::FRONT, GL::SHININESS, no_shininess);
    GL::Material(GL::FRONT, GL::EMISSION, no_mat);
    GLUT::SolidSphere(1.0, 16, 16);
    GL::PopMatrix();

#/*  draw sphere in first row, second column
# *  diffuse and specular reflection; low shininess; no ambient
# */
    GL::PushMatrix();
    GL::Translate(-1.25, 3.0, 0.0);
    GL::Material(GL::FRONT, GL::AMBIENT, no_mat);
    GL::Material(GL::FRONT, GL::DIFFUSE, mat_diffuse);
    GL::Material(GL::FRONT, GL::SPECULAR, mat_specular);
    GL::Material(GL::FRONT, GL::SHININESS, low_shininess);
    GL::Material(GL::FRONT, GL::EMISSION, no_mat);
    GLUT::SolidSphere(1.0, 16, 16);
    GL::PopMatrix();

#/*  draw sphere in first row, third column
# *  diffuse and specular reflection; high shininess; no ambient
# */
    GL::PushMatrix();
    GL::Translate(1.25, 3.0, 0.0);
    GL::Material(GL::FRONT, GL::AMBIENT, no_mat);
    GL::Material(GL::FRONT, GL::DIFFUSE, mat_diffuse);
    GL::Material(GL::FRONT, GL::SPECULAR, mat_specular);
    GL::Material(GL::FRONT, GL::SHININESS, high_shininess);
    GL::Material(GL::FRONT, GL::EMISSION, no_mat);
    GLUT::SolidSphere(1.0, 16, 16);
    GL::PopMatrix();

#/*  draw sphere in first row, fourth column
# *  diffuse reflection; emission; no ambient or specular reflection
# */
    GL::PushMatrix();
    GL::Translate(3.75, 3.0, 0.0);
    GL::Material(GL::FRONT, GL::AMBIENT, no_mat);
    GL::Material(GL::FRONT, GL::DIFFUSE, mat_diffuse);
    GL::Material(GL::FRONT, GL::SPECULAR, no_mat);
    GL::Material(GL::FRONT, GL::SHININESS, no_shininess);
    GL::Material(GL::FRONT, GL::EMISSION, mat_emission);
    GLUT::SolidSphere(1.0, 16, 16);
    GL::PopMatrix();

#/*  draw sphere in second row, first column
# *  ambient and diffuse reflection; no specular  
# */
    GL::PushMatrix();
    GL::Translate(-3.75, 0.0, 0.0);
    GL::Material(GL::FRONT, GL::AMBIENT, mat_ambient);
    GL::Material(GL::FRONT, GL::DIFFUSE, mat_diffuse);
    GL::Material(GL::FRONT, GL::SPECULAR, no_mat);
    GL::Material(GL::FRONT, GL::SHININESS, no_shininess);
    GL::Material(GL::FRONT, GL::EMISSION, no_mat);
    GLUT::SolidSphere(1.0, 16, 16);
    GL::PopMatrix();

#/*  draw sphere in second row, second column
# *  ambient, diffuse and specular reflection; low shininess
# */
    GL::PushMatrix();
    GL::Translate(-1.25, 0.0, 0.0);
    GL::Material(GL::FRONT, GL::AMBIENT, mat_ambient);
    GL::Material(GL::FRONT, GL::DIFFUSE, mat_diffuse);
    GL::Material(GL::FRONT, GL::SPECULAR, mat_specular);
    GL::Material(GL::FRONT, GL::SHININESS, low_shininess);
    GL::Material(GL::FRONT, GL::EMISSION, no_mat);
    GLUT::SolidSphere(1.0, 16, 16);
    GL::PopMatrix();

#/*  draw sphere in second row, third column
# *  ambient, diffuse and specular reflection; high shininess
# */
    GL::PushMatrix();
    GL::Translate(1.25, 0.0, 0.0);
    GL::Material(GL::FRONT, GL::AMBIENT, mat_ambient);
    GL::Material(GL::FRONT, GL::DIFFUSE, mat_diffuse);
    GL::Material(GL::FRONT, GL::SPECULAR, mat_specular);
    GL::Material(GL::FRONT, GL::SHININESS, high_shininess);
    GL::Material(GL::FRONT, GL::EMISSION, no_mat);
    GLUT::SolidSphere(1.0, 16, 16);
    GL::PopMatrix();

#/*  draw sphere in second row, fourth column
# *  ambient and diffuse reflection; emission; no specular
# */
    GL::PushMatrix();
    GL::Translate(3.75, 0.0, 0.0);
    GL::Material(GL::FRONT, GL::AMBIENT, mat_ambient);
    GL::Material(GL::FRONT, GL::DIFFUSE, mat_diffuse);
    GL::Material(GL::FRONT, GL::SPECULAR, no_mat);
    GL::Material(GL::FRONT, GL::SHININESS, no_shininess);
    GL::Material(GL::FRONT, GL::EMISSION, mat_emission);
    GLUT::SolidSphere(1.0, 16, 16);
    GL::PopMatrix();

#/*  draw sphere in third row, first column
# *  colored ambient and diffuse reflection; no specular  
# */
    GL::PushMatrix();
    GL::Translate(-3.75, -3.0, 0.0);
    GL::Material(GL::FRONT, GL::AMBIENT, mat_ambient_color);
    GL::Material(GL::FRONT, GL::DIFFUSE, mat_diffuse);
    GL::Material(GL::FRONT, GL::SPECULAR, no_mat);
    GL::Material(GL::FRONT, GL::SHININESS, no_shininess);
    GL::Material(GL::FRONT, GL::EMISSION, no_mat);
    GLUT::SolidSphere(1.0, 16, 16);
    GL::PopMatrix();

#/*  draw sphere in third row, second column
# *  colored ambient, diffuse and specular reflection; low shininess
# */
    GL::PushMatrix();
    GL::Translate(-1.25, -3.0, 0.0);
    GL::Material(GL::FRONT, GL::AMBIENT, mat_ambient_color);
    GL::Material(GL::FRONT, GL::DIFFUSE, mat_diffuse);
    GL::Material(GL::FRONT, GL::SPECULAR, mat_specular);
    GL::Material(GL::FRONT, GL::SHININESS, low_shininess);
    GL::Material(GL::FRONT, GL::EMISSION, no_mat);
    GLUT::SolidSphere(1.0, 16, 16);
    GL::PopMatrix();

#/*  draw sphere in third row, third column
# *  colored ambient, diffuse and specular reflection; high shininess
# */
    GL::PushMatrix();
    GL::Translate(1.25, -3.0, 0.0);
    GL::Material(GL::FRONT, GL::AMBIENT, mat_ambient_color);
    GL::Material(GL::FRONT, GL::DIFFUSE, mat_diffuse);
    GL::Material(GL::FRONT, GL::SPECULAR, mat_specular);
    GL::Material(GL::FRONT, GL::SHININESS, high_shininess);
    GL::Material(GL::FRONT, GL::EMISSION, no_mat);
    GLUT::SolidSphere(1.0, 16, 16);
    GL::PopMatrix();

#/*  draw sphere in third row, fourth column
# *  colored ambient and diffuse reflection; emission; no specular
# */
    GL::PushMatrix();
    GL::Translate(3.75, -3.0, 0.0);
    GL::Material(GL::FRONT, GL::AMBIENT, mat_ambient_color);
    GL::Material(GL::FRONT, GL::DIFFUSE, mat_diffuse);
    GL::Material(GL::FRONT, GL::SPECULAR, no_mat);
    GL::Material(GL::FRONT, GL::SHININESS, no_shininess);
    GL::Material(GL::FRONT, GL::EMISSION, mat_emission);
    GLUT::SolidSphere(1.0, 16, 16);
    GL::PopMatrix();

    GL::Flush();
}

myReshape = proc {|w, h|
    GL::Viewport(0, 0, w, h);
    GL::MatrixMode(GL::PROJECTION);
    GL::LoadIdentity();
    if (w <= (h * 2))
	GL::Ortho (-6.0, 6.0, -3.0*(h.to_f*2)/w, 
	    3.0*(h.to_f*2)/w, -10.0, 10.0);
    else
	GL::Ortho (-6.0*w.to_f/(h*2), 
	    6.0*w.to_f/(h*2), -3.0, 3.0, -10.0, 10.0);
    end
    GL::MatrixMode(GL::MODELVIEW);
}

#/*  Main Loop
# *  Open window with initial window size, title bar, 
# *  RGBA display mode, and handle input events.
# */
    GLUT::Init();
    GLUT::InitDisplayMode (GLUT::SINGLE | GLUT::RGB | GLUT::DEPTH);
    GLUT::InitWindowSize (600, 450);
    GLUT::CreateWindow();
    myinit();
    GLUT::ReshapeFunc(myReshape);
    GLUT::DisplayFunc(display);
    GLUT::MainLoop();

