#/*
# * Copyright (c) 1993-1997, 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# * Unpublished-- rights reserved under the copyright laws of the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(R) is a registered trademark of Silicon Graphics, Inc.
# */
#
#/*
# *  list.c
# *  This program demonstrates how to make and execute a 
# *  display list.  Note that attributes, such as current 
# *  color and matrix, are changed.
# */
require "opengl"
require "glut"
require "mathn"

$listName = 0;

def init
   $listName = GL.GenLists(1);
   GL.NewList($listName, GL::COMPILE);
      GL.Color(1.0, 0.0, 0.0);  # /*  current color red  */
      GL.Begin(GL::TRIANGLES);
      GL.Vertex(0.0, 0.0);
      GL.Vertex(1.0, 0.0);
      GL.Vertex(0.0, 1.0);
      GL.End();
      GL.Translate(1.5, 0.0, 0.0); # /*  move position  */
   GL.EndList();
   GL.ShadeModel(GL::FLAT);
end

def drawLine
   GL.Begin(GL::LINES);
   GL.Vertex(0.0, 0.5);
   GL.Vertex(15.0, 0.5);
   GL.End();
end

display = Proc.new {
   GL.Clear(GL::COLOR_BUFFER_BIT);
   GL.Color(0.0, 1.0, 0.0);  # /*  current color green  */
   for i in (0..9 ) #  /*  draw 10 triangles    */
      GL.CallList($listName);
   end
   drawLine();  # /*  is this line green?  NO!  */
                 # /*  where is the line drawn?  */
   GL.Flush();
}

reshape = Proc.new {|w, h|
   GL.Viewport(0, 0, w, h);
   GL.MatrixMode(GL::PROJECTION);
   GL.LoadIdentity();
   if (w <= h) 
      GLU.Ortho2D(0.0, 2.0, -0.5 * h/w, 1.5 * h/w);
   else
      GLU.Ortho2D(0.0, 2.0 * w/h, -0.5, 1.5); 
   end
   GL.MatrixMode(GL::MODELVIEW);
   GL.LoadIdentity();
}

# /* ARGSUSED1 */
keyboard = Proc.new {|key, x, y|
   case (key)
      when 27
         exit(0);
   end
}

# /*  Main Loop
#  *  Open window with initial window size, title bar, 
#  *  RGBA display mode, and handle input events.
#  */
# int main(int argc, char** argv)
# {
   GLUT.Init
   GLUT.InitDisplayMode(GLUT::SINGLE | GLUT::RGB);
   GLUT.InitWindowSize(650, 50);
   GLUT.CreateWindow($0);
   init();
   GLUT.ReshapeFunc(reshape);
   GLUT.DisplayFunc(display);
   GLUT.KeyboardFunc(keyboard);
   GLUT.MainLoop();
#   return 0;
#}
