test/OpenGL/tutorial/lesson03.sdlpl

   1 #!/usr/bin/env perl
   2 #
   3 # lesson03.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 use strict;
  31 use Getopt::Long;
  32 use SDL;
  33 use SDL::App;
  34 use SDL::OpenGL;
  35 use SDL::Event;
  36
  37 my $arg_screen_width =640;
  38 my $arg_screen_height=512;
  39 my $arg_fullscreen=0;
  40
  41 GetOptions(
  42            "width:i"        => \$arg_screen_width,
  43            "height:i"       => \$arg_screen_height,
  44            "fullscreen!"    => \$arg_fullscreen,
  45           ) or die $!;
  46
  47 main();
  48 exit;
  49
  50
  51 sub main
  52   {
  53    my $done=0;
  54
  55    my $app = new SDL::App ( -title => "Jeff Molofee's GL Code Tutorial ... NeHe '99",
  56                             -icon => "icon.png",
  57                             -width => $arg_screen_width,
  58                             -height =>$arg_screen_height,
  59                              -d => 16,
  60                              -opengl => 1,
  61                           );
  62    $app->fullscreen() if $arg_fullscreen;
  63
  64    SDL::ShowCursor(0);
  65
  66    my $event = new SDL::Event;
  67    $event->set(SDL_SYSWMEVENT,SDL_IGNORE);#
  68
  69
  70
  71    InitGL($arg_screen_width, $arg_screen_height);
  72
  73    while ( ! $done ) {
  74
  75     DrawGLScene();
  76
  77     $app->sync();
  78
  79     $event->pump;
  80     $event->poll;
  81
  82
  83     if ( $event->type == SDL_QUIT ) {
  84      $done = 1;
  85     }
  86
  87     if ( $event->type == SDL_KEYDOWN ) {
  88      if ( $event->key_sym == SDLK_ESCAPE ) {
  89       $done = 1;
  90      }
  91     }
  92    }
  93   }
  94
  95
  96
  97
  98
  99
 100 #########################################################################
 101 #Pretty much in original form, but 'Perlised'
 102
 103
 104 sub InitGL
 105   {
 106    my ($Width, $Height)=@_;
 107
 108    glViewport(0, 0, $Width, $Height);
 109    glClearColor(0.0, 0.0, 0.0, 0.0);                            # This Will Clear The Background Color To Black
 110    glClearDepth(1.0);                                           # Enables Clearing Of The Depth Buffer
 111    glDepthFunc(GL_LESS);                                        # The Type Of Depth Test To Do
 112    glEnable(GL_DEPTH_TEST);                                     # Enables Depth Testing
 113    glShadeModel(GL_SMOOTH);                                     # Enables Smooth Color Shading
 114
 115    glMatrixMode(GL_PROJECTION);
 116    glLoadIdentity();                                            # Reset The Projection Matrix
 117
 118    gluPerspective(45.0, $Width/$Height, 0.1, 100.0);            # Calculate The Aspect Ratio Of The Window
 119
 120    glMatrixMode(GL_MODELVIEW);
 121   }
 122
 123
 124
 125 # The main drawing function.
 126 sub DrawGLScene
 127   {
 128    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);          # Clear The Screen And The Depth Buffer
 129    glLoadIdentity();                                            # Reset The View
 130
 131    glTranslate(-1.5,0.0,-6.0);          # Move Left 1.5 Units And Into The Screen 6.0
 132
 133    # draw a triangle (in smooth coloring mode)
 134    glBegin(GL_POLYGON);                         # start drawing a polygon
 135    glColor(1.0,0.0,0.0);                        # Set The Color To Red
 136    glVertex( 0.0, 1.0, 0.0);                    # Top
 137    glColor(0.0,1.0,0.0);                        # Set The Color To Green
 138    glVertex( 1.0,-1.0, 0.0);                    # Bottom Right
 139    glColor(0.0,0.0,1.0);                        # Set The Color To Blue
 140    glVertex(-1.0,-1.0, 0.0);                    # Bottom Left
 141    glEnd();                                     # we're done with the polygon (smooth color interpolation)
 142
 143    glTranslate(3.0,0.0,0.0);                    # Move Right 3 Units
 144
 145    # draw a square (quadrilateral)
 146    glColor(0.5,0.5,1.0);                        # set color to a blue shade.
 147    glBegin(GL_QUADS);                           # start drawing a polygon (4 sided)
 148    glVertex(-1.0, 1.0, 0.0);                    # Top Left
 149    glVertex( 1.0, 1.0, 0.0);                    # Top Right
 150    glVertex( 1.0,-1.0, 0.0);                    # Bottom Right
 151    glVertex(-1.0,-1.0, 0.0);                    # Bottom Left
 152    glEnd();                                     # done with the polygon
 153
 154
 155
 156
 157   }
 158
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 160
 161