test/OpenGL/tutorial/lesson02.sdlpl

   1 #!/usr/bin/env perl
   2 #
   3 # lesson02.pl
   4 #
   5 # Copyright (C) 2005 David J. Goehrig <dgoehrig@cpan.org>
   6 #
   7 # ------------------------------------------------------------------------------
   8 #
   9 # This library is free software; you can redistribute it and/or
  10 # modify it under the terms of the GNU Lesser General Public
  11 # License as published by the Free Software Foundation; either
  12 # version 2.1 of the License, or (at your option) any later version.
  13 #
  14 # This library is distributed in the hope that it will be useful,
  15 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17 # Lesser General Public License for more details.
  18 #
  19 # You should have received a copy of the GNU Lesser General Public
  20 # License along with this library; if not, write to the Free Software
  21 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  22 #
  23 # ------------------------------------------------------------------------------
  24 #
  25 # Please feel free to send questions, suggestions or improvements to:
  26 #
  27 #       David J. Goehrig
  28 #       dgoehrig@cpan.org
  29 #
  30
  31 use strict;
  32 use Getopt::Long;
  33 use SDL;
  34 use SDL::App;
  35 use SDL::OpenGL;
  36 use SDL::Event;
  37
  38 my $arg_screen_width =640;
  39 my $arg_screen_height=512;
  40 my $arg_fullscreen=0;
  41
  42 GetOptions(
  43            "width:i"        => \$arg_screen_width,
  44            "height:i"       => \$arg_screen_height,
  45            "fullscreen!"    => \$arg_fullscreen,
  46
  47           ) or die $!;
  48
  49 main();
  50 exit;
  51
  52
  53 sub main
  54   {
  55    my $done=0;
  56
  57    my $app = new SDL::App ( -title => "Jeff Molofee's GL Code Tutorial ... NeHe '99",
  58                             -icon => "icon.png",
  59                             -width => $arg_screen_width,
  60                             -height =>$arg_screen_height,
  61                             -d => 16,
  62                             -gl => 1,
  63
  64                           );
  65         $app->fullscreen() if ($arg_fullscreen);
  66
  67    SDL::ShowCursor (0);
  68
  69    my $event = new SDL::Event;
  70    $event->set(SDL_SYSWMEVENT,SDL_IGNORE);#
  71
  72    InitGL($arg_screen_width, $arg_screen_height);
  73
  74    while ( ! $done ) {
  75
  76     DrawGLScene();
  77
  78     $app->sync();
  79
  80     $event->pump;
  81     $event->poll;
  82
  83
  84     if ( $event->type == SDL_QUIT ) {
  85      $done = 1;
  86     }
  87
  88     if ( $event->type == SDL_KEYDOWN ) {
  89      if ( $event->key_sym == SDLK_ESCAPE ) {
  90       $done = 1;
  91      }
  92     }
  93    }
  94   }
  95
  96
  97
  98
  99
 100
 101 #########################################################################
 102 #Pretty much in original form, but 'Perlised'
 103
 104
 105 sub InitGL
 106   {
 107    my ($Width, $Height)=@_;
 108
 109    glViewport(0, 0, $Width, $Height);
 110    glClearColor(0.0, 0.0, 0.0, 0.0);                            # This Will Clear The Background Color To Black
 111    glClearDepth(1.0);                                           # Enables Clearing Of The Depth Buffer
 112    glDepthFunc(GL_LESS());                                      # The Type Of Depth Test To Do
 113    glEnable(GL_DEPTH_TEST());                                   # Enables Depth Testing
 114    glShadeModel(GL_SMOOTH());                                   # Enables Smooth Color Shading
 115
 116    glMatrixMode(GL_PROJECTION());
 117    glLoadIdentity();                                            # Reset The Projection Matrix
 118
 119    gluPerspective(45.0, $Width/$Height, 0.1, 100.0);            # Calculate The Aspect Ratio Of The Window
 120
 121    glMatrixMode(GL_MODELVIEW());
 122   }
 123
 124
 125
 126 # The main drawing function.
 127 sub DrawGLScene
 128   {
 129    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);          # Clear The Screen And The Depth Buffer
 130    glLoadIdentity();                                            # Reset The View
 131
 132    glTranslate(-1.5,0.0,-6.0);                                  # Move Left 1.5 Units And Into The Screen 6.0
 133
 134    # draw a triangle
 135    glBegin(GL_POLYGON);                                         # start drawing a polygon
 136    glVertex( 0.0, 1.0, 0.0);                                    # Top
 137    glVertex( 1.0,-1.0, 0.0);                                    # Bottom Right
 138    glVertex(-1.0,-1.0, 0.0);                                    # Bottom Left
 139    glEnd();                                                     # we're done with the polygon
 140
 141    glTranslate(3.0,0.0,0.0);                                    # Move Right 3 Units
 142
 143    # draw a square (quadrilateral)
 144    glBegin(GL_QUADS);                                           # start drawing a polygon (4 sided)
 145    glVertex(-1.0, 1.0, 0.0);                                    # Top Left
 146    glVertex( 1.0, 1.0, 0.0);                                    # Top Right
 147    glVertex( 1.0,-1.0, 0.0);                                    # Bottom Right
 148    glVertex(-1.0,-1.0, 0.0);                                    # Bottom Left
 149    glEnd();                                                     # done with the polygon
 150
 151
 152   }
 153
 154
 155
 156