#!/usr/bin/perl

use strict;
use warnings;
use SDL::App;
use SDL::OpenGL;

my ($done, $frame);
my ($conf, $sdl_app);

START: main();


sub main
{
    init();
    main_loop();
    cleanup();
}
sub init
{
    $| = 1;
    init_conf();
    init_window();
}
sub init_conf
{
    $conf = {
        title  => 'Game',
        width  => 1200,
        height => 900,
        fovy   => 125,
    };
}
sub init_window
{
    my ($title, $w, $h) = @$conf{qw( title width height )};

    $sdl_app = SDL::App->new(-title  => $title,
                             -width  => $w,
                             -height => $h,
                             -gl     => 1,
                            );
    SDL::ShowCursor(0);
}
sub main_loop
{
    while (not $done) {
        $frame++;
        do_frame();
    }
}
sub do_frame
{
    prep_frame();
    draw_frame();
    end_frame();
}
sub prep_frame
{
    glClear(GL_COLOR_BUFFER_BIT);
}
sub draw_frame
{
    set_projection_3d();
    set_view_3d();
    draw_view();

    print '.';
    sleep 1;
    $done = 1 if $frame == 4;
}
sub set_projection_3d
{
    my ($fovy, $w, $h) = @$conf{qw( fovy width height )};
    my $aspect = $w / $h;

    glMatrixMode(GL_PROJECTION);
    glLoadIdentity;
    gluPerspective($fovy, $aspect, 1, 1000);

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity;
}
sub set_view_3d
{
    # Move the viewpoint so we can see the origin
    glTranslate(0, -2, -10);
}
sub draw_view
{
    gen_fractal();
    
}
sub iterate
{
my $inp=$_[0];
my $iterations=$_[1];
my(%rules) = @_;
my $out=$inp;
my $i;
for (my $i2=0;$i2<$iterations;$i2++){
$inp=$out;
foreach $i (split(//,$inp)){
$out.= $rules{$i};}
}
return $out;
}
sub gen_fractal()
{
    my %rule = ( 'n' , 'nlnrrnln',
           'l' ,    'lnrnrnlln',
           "L",    'LnnRnnL',
           "r", 'rnllnrrn',
           "R",'RnnLnnR');
        my %rule2 = ( 'n' , 0,
           'l' ,    60,
           "L",    120,
           "r", -60,
           "R",-120,
           "F",0);
           my ($count,$posi,$a2);
           my @pos=(0,0,0);
           my @oldpos=(0,0,0);
           my ($x,$y,$z,$rot,$flux,$cnt);
    foreach my $a(split(//,iterate('nLnLnL',4,%rule))){
        $cnt+=1;
        $rot+=.01745*$rule2{$a};
        if ($a eq'n'){
        $x=cos($rot);
        $y=sin($rot);
    }else{$x=0;$y=0}
        @pos=($pos[0]+$x,$pos[1]+$y,0);
        for (my $step=0;$step<10;$step++){
        draw_cube([$pos[0]-($x/10*$step),$pos[1]-($y/10*$step),$pos[2]],.03,(.2,.2,.2));}
        
    }
@oldpos=($pos[0],$pos[1],0)
}

sub draw_axes
{
    # Lines from origin along positive axes, for orientation
    # X axis = red, Y axis = green, Z axis = blue
    glBegin(GL_LINES);
    glColor(1, 0, 0);
    glVertex(0, 0, 0);
    glVertex(1, 0, 0);

    glColor(0, 1, 0);
    glVertex(0, 0, 0);
    glVertex(0, 1, 0);

    glColor(0, 0, 1);
    glVertex(0, 0, 0);
    glVertex(0, 0, 1);
    glEnd;
}

sub draw_cube
{
    # A simple cube
    my $s =$_[1];
    my (@col)=@_;
    my $x= $_[0][0];my $y= $_[0][1];my $z= $_[0][2];
    my @indices = qw( 4 5 6 7   1 2 6 5   0 1 5 4
                      0 3 2 1   0 4 7 3   2 3 7 6 );
    glColor($col[0], $col[1], $col[2]);
    my @vertices = ([-$s+$x, -$s+$y, -$s+$z], [ $s+$x, -$s+$y, -$s+$z],
                    [ $s+$x,  $s+$y, -$s+$z], [-$s+$x,  $s+$y, -$s+$z],
                    [-$s+$x, -$s+$y,  $s+$z], [ $s+$x, -$s+$y,  $s+$z],
                    [ $s+$x,  $s+$y,  $s+$z], [-$s+$x,  $s+$y,  $s+$z]);

    glBegin(GL_QUADS);
    foreach my $face (0 .. 5) {
        foreach my $vertex (0 .. 3) {
            my $index  = $indices[4 * $face + $vertex];
            my $coords = $vertices[$index];
            glVertex(@$coords);
        }
    }
    glEnd;
}
sub end_frame
{
    $sdl_app->sync;
}
sub cleanup
{
    print "\nDone.\n"
}