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#!/usr/bin/perl
# This code was created by Jeff Molofee '99
# (ported to SDL by Sam Lantinga '2000)
# (ported to Perl/SDL by Wayne Keenan '2000)
#
# If you've found this code useful, please let me know.
#
# Visit me at www.demonews.com/hosted/nehe
use strict;
use Getopt::Long;
use SDL::App;
use SDL::OpenGL;
use SDL::Event;
use SDL::Cursor;
my $arg_screen_width =640;
my $arg_screen_height=512;
my $arg_fullscreen=0;
my $delay = 30;
GetOptions(
"width:i" => \$arg_screen_width,
"height:i" => \$arg_screen_height,
"fullscreen!" => \$arg_fullscreen,
"delay:i" => \$delay,
) or die $!;
main();
exit;
sub main
{
my $done=0;
my $app = new SDL::App ( -title => "Jeff Molofee's GL Code Tutorial ... NeHe '99",
-icon => "icon.png",
-width => $arg_screen_width,
-height =>$arg_screen_height,
-opengl => 1,
);
$app->fullscreen if ($arg_fullscreen);
SDL::ShowCursor(0);
my $event = new SDL::Event;
$event->set(SDL_SYSWMEVENT(),SDL_IGNORE());#
InitGL($arg_screen_width, $arg_screen_height);
while ( ! $done ) {
DrawGLScene();
$app->sync();
$app->delay($delay);
$event->pump;
$event->poll;
if ( $event->type == SDL_QUIT() ) {
$done = 1;
}
if ( $event->type == SDL_KEYDOWN() ) {
if ( $event->key_sym == SDLK_ESCAPE() ) {
$done = 1;
}
}
}
}
#########################################################################
#Pretty much in original form, but 'Perlised'
#/* rotation angle for the triangle. */
my $rtri = 0.0;
#/* rotation angle for the quadrilateral. */
my $rquad = 0.0;
sub InitGL
{
my ($Width, $Height)=@_;
glViewport(0, 0, $Width, $Height);
glClearColor(0.0, 0.0, 0.0, 0.0); # This Will Clear The Background Color To Black
glClearDepth(1.0); # Enables Clearing Of The Depth Buffer
glDepthFunc(GL_LESS); # The Type Of Depth Test To Do
glEnable(GL_DEPTH_TEST); # Enables Depth Testing
glShadeModel(GL_SMOOTH); # Enables Smooth Color Shading
glMatrixMode(GL_PROJECTION);
glLoadIdentity(); # Reset The Projection Matrix
gluPerspective(45.0, $Width/$Height, 0.1, 100.0); # Calculate The Aspect Ratio Of The Window
glMatrixMode(GL_MODELVIEW);
}
# The main drawing function.
sub DrawGLScene
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); # Clear The Screen And The Depth Buffer
glLoadIdentity(); # Reset The View
glTranslate(-1.5,0.0,-6.0); # Move Left 1.5 Units And Into The Screen 6.0
glRotate($rtri,0.0,1.0,0.0); # Rotate The Pyramid On The Y axis
# draw a pyramid (in smooth coloring mode)
glBegin(GL_POLYGON); # start drawing a pyramid
# front face of pyramid
glColor(1.0,0.0,0.0); # Set The Color To Red
glVertex(0.0, 1.0, 0.0); # Top of triangle (front)
glColor(0.0,1.0,0.0); # Set The Color To Green
glVertex(-1.0,-1.0, 1.0); # left of triangle (front)
glColor(0.0,0.0,1.0); # Set The Color To Blue
glVertex(1.0,-1.0, 1.0); # right of traingle (front)
# right face of pyramid
glColor(1.0,0.0,0.0); # Red
glVertex( 0.0, 1.0, 0.0); # Top Of Triangle (Right)
glColor(0.0,0.0,1.0); # Blue
glVertex( 1.0,-1.0, 1.0); # Left Of Triangle (Right)
glColor(0.0,1.0,0.0); # Green
glVertex( 1.0,-1.0, -1.0); # Right Of Triangle (Right)
# back face of pyramid
glColor(1.0,0.0,0.0); # Red
glVertex( 0.0, 1.0, 0.0); # Top Of Triangle (Back)
glColor(0.0,1.0,0.0); # Green
glVertex( 1.0,-1.0, -1.0); # Left Of Triangle (Back)
glColor(0.0,0.0,1.0); # Blue
glVertex(-1.0,-1.0, -1.0); # Right Of Triangle (Back)
# left face of pyramid.
glColor(1.0,0.0,0.0); # Red
glVertex( 0.0, 1.0, 0.0); # Top Of Triangle (Left)
glColor(0.0,0.0,1.0); # Blue
glVertex(-1.0,-1.0,-1.0); # Left Of Triangle (Left)
glColor(0.0,1.0,0.0); # Green
glVertex(-1.0,-1.0, 1.0); # Right Of Triangle (Left)
glEnd(); # Done Drawing The Pyramid
glLoadIdentity(); # make sure we're no longer rotated.
glTranslate(1.5,0.0,-7.0); # Move Right 3 Units, and back into the screen 7
glRotate($rquad,1.0,1.0,1.0); # Rotate The Cube On X, Y, and Z
# draw a cube (6 quadrilaterals)
glBegin(GL_QUADS); # start drawing the cube.
# top of cube
glColor(0.0,1.0,0.0); # Set The Color To Blue
glVertex( 1.0, 1.0,-1.0); # Top Right Of The Quad (Top)
glVertex(-1.0, 1.0,-1.0); # Top Left Of The Quad (Top)
glVertex(-1.0, 1.0, 1.0); # Bottom Left Of The Quad (Top)
glVertex( 1.0, 1.0, 1.0); # Bottom Right Of The Quad (Top)
# bottom of cube
glColor(1.0,0.5,0.0); # Set The Color To Orange
glVertex( 1.0,-1.0, 1.0); # Top Right Of The Quad (Bottom)
glVertex(-1.0,-1.0, 1.0); # Top Left Of The Quad (Bottom)
glVertex(-1.0,-1.0,-1.0); # Bottom Left Of The Quad (Bottom)
glVertex( 1.0,-1.0,-1.0); # Bottom Right Of The Quad (Bottom)
# front of cube
glColor(1.0,0.0,0.0); # Set The Color To Red
glVertex( 1.0, 1.0, 1.0); # Top Right Of The Quad (Front)
glVertex(-1.0, 1.0, 1.0); # Top Left Of The Quad (Front)
glVertex(-1.0,-1.0, 1.0); # Bottom Left Of The Quad (Front)
glVertex( 1.0,-1.0, 1.0); # Bottom Right Of The Quad (Front)
# back of cube.
glColor(1.0,1.0,0.0); # Set The Color To Yellow
glVertex( 1.0,-1.0,-1.0); # Top Right Of The Quad (Back)
glVertex(-1.0,-1.0,-1.0); # Top Left Of The Quad (Back)
glVertex(-1.0, 1.0,-1.0); # Bottom Left Of The Quad (Back)
glVertex( 1.0, 1.0,-1.0); # Bottom Right Of The Quad (Back)
# left of cube
glColor(0.0,0.0,1.0); # Blue
glVertex(-1.0, 1.0, 1.0); # Top Right Of The Quad (Left)
glVertex(-1.0, 1.0,-1.0); # Top Left Of The Quad (Left)
glVertex(-1.0,-1.0,-1.0); # Bottom Left Of The Quad (Left)
glVertex(-1.0,-1.0, 1.0); # Bottom Right Of The Quad (Left)
# Right of cube
glColor(1.0,0.0,1.0); # Set The Color To Violet
glVertex( 1.0, 1.0,-1.0); # Top Right Of The Quad (Right)
glVertex( 1.0, 1.0, 1.0); # Top Left Of The Quad (Right)
glVertex( 1.0,-1.0, 1.0); # Bottom Left Of The Quad (Right)
glVertex( 1.0,-1.0,-1.0); # Bottom Right Of The Quad (Right)
glEnd(); # Done Drawing The Cube
$rtri+=15.0; # Increase The Rotation Variable For The Triangle
$rquad-=15.0; # Decrease The Rotation Variable For The Quad
}
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