test/OpenGL/tutorial/lesson04.pl

   1 #!/usr/bin/perl -w
   2 # This code was created by Jeff Molofee '99
   3 # (ported to SDL by Sam Lantinga '2000)
   4 # (ported to Perl/SDL by Wayne Keenan '2000)
   5 #
   6 # If you've found this code useful, please let me know.
   7 #
   8 # Visit me at www.demonews.com/hosted/nehe
   9
  10 use strict;
  11 use Getopt::Long;
  12
  13 use SDL;
  14 use SDL::App;
  15 use SDL::OpenGL;
  16 use SDL::Event;
  17
  18 my $arg_screen_width =640;
  19 my $arg_screen_height=512;
  20 my $arg_fullscreen=0;
  21 my $delay=30;
  22
  23 GetOptions(
  24            "width:i"        => \$arg_screen_width,
  25            "height:i"       => \$arg_screen_height,
  26            "fullscreen!"    => \$arg_fullscreen,
  27            "delay:i"        => \$delay,
  28           ) or die <<USAGE;
  29 Usage $0 -w 800 -h 600 -d 10 --fullscreen
  30 USAGE
  31
  32 #/* rotation angle for the triangle. */
  33 my $rtri = 0.0;
  34
  35 #/* rotation angle for the quadrilateral. */
  36 my $rquad = 0.0;
  37
  38
  39 main();
  40 exit;
  41
  42
  43 sub main
  44   {
  45    my $done=0;
  46    my $app = new SDL::App ( -title => "Jeff Molofee's GL Code Tutorial ... NeHe '99",
  47                             -icon => "icon.png",
  48                             -width => $arg_screen_width,
  49                             -height =>$arg_screen_height,
  50                             -gl => 1,
  51                           );
  52    $app->fullscreen() if $arg_fullscreen;
  53
  54    SDL::ShowCursor(0);
  55
  56    my $event = new SDL::Event;
  57    $event->set(SDL_SYSWMEVENT,SDL_IGNORE);#
  58
  59
  60
  61    InitGL($arg_screen_width, $arg_screen_height);
  62
  63    while ( ! $done ) {
  64
  65     DrawGLScene();
  66
  67     $app->sync();
  68     $app->delay($delay);
  69
  70     $event->pump;
  71     $event->poll;
  72
  73
  74     if ( $event->type == SDL_QUIT ) {
  75      $done = 1;
  76     }
  77
  78     if ( $event->type == SDL_KEYDOWN ) {
  79      if ( $event->key_sym == SDLK_ESCAPE ) {
  80       $done = 1;
  81      }
  82     }
  83    }
  84   }
  85
  86
  87
  88
  89
  90
  91 #########################################################################
  92 #Pretty much in original form, but 'Perlised'
  93
  94
  95
  96
  97
  98 sub InitGL
  99   {
 100    my ($Width, $Height)=@_;
 101
 102    glViewport(0, 0, $Width, $Height);
 103    glClearColor(0.0, 0.0, 0.0, 0.0);                            # This Will Clear The Background Color To Black
 104    glClearDepth(1.0);                                           # Enables Clearing Of The Depth Buffer
 105    glDepthFunc(GL_LESS);                                        # The Type Of Depth Test To Do
 106    glEnable(GL_DEPTH_TEST);                                     # Enables Depth Testing
 107    glShadeModel(GL_SMOOTH);                                     # Enables Smooth Color Shading
 108
 109    glMatrixMode(GL_PROJECTION);
 110    glLoadIdentity();                                            # Reset The Projection Matrix
 111
 112    gluPerspective(45.0, $Width/$Height, 0.1, 100.0);            # Calculate The Aspect Ratio Of The Window
 113
 114    glMatrixMode(GL_MODELVIEW);
 115   }
 116
 117
 118
 119 # The main drawing function.
 120 sub DrawGLScene
 121   {
 122    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);          # Clear The Screen And The Depth Buffer
 123    glLoadIdentity();                                            # Reset The View
 124
 125    glTranslate(-1.5,0.0,-6.0);          # Move Left 1.5 Units And Into The Screen 6.0
 126
 127   glRotate($rtri,0.0,1.0,0.0);          # Rotate The Triangle On The Y axis
 128   # draw a triangle (in smooth coloring mode)
 129   glBegin(GL_POLYGON);                          # start drawing a polygon
 130   glColor(1.0,0.0,0.0);                 # Set The Color To Red
 131   glVertex( 0.0, 1.0, 0.0);             # Top
 132   glColor(0.0,1.0,0.0);                 # Set The Color To Green
 133   glVertex( 1.0,-1.0, 0.0);             # Bottom Right
 134   glColor(0.0,0.0,1.0);                 # Set The Color To Blue
 135   glVertex(-1.0,-1.0, 0.0);             # Bottom Left
 136   glEnd();                                      # we're done with the polygon (smooth color interpolation)
 137
 138   glLoadIdentity();                             # make sure we're no longer rotated.
 139   glTranslate(1.5,0.0,-6.0);            # Move Right 3 Units, and back into the screen 6.0
 140
 141   glRotate($rquad,1.0,0.0,0.0);         # Rotate The Quad On The X axis
 142   # draw a square (quadrilateral)
 143   glColor(0.5,0.5,1.0);                 # set color to a blue shade.
 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   $rtri+=15.0;                                  # Increase The Rotation Variable For The Triangle
 152   $rquad-=15.0;                                 # Decrease The Rotation Variable For The Quad
 153
 154
 155   }
 156
 157
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 159