#! perl -slw
use strict;
use threads;
use Thread::Queue;
use Time::HiRes qw[ time ];
use GD;

sub rgb2n{ local $^W; unpack 'N', pack 'CCCC', 0, @_ }

my $i = GD::Image->new( 1000, 1000, 1 );

my $start = time;
for my $y ( 0 .. 999 ) {
    for my $x ( 0 .. 999 ) {
        $i->setPixel( $x, $y, rgb2n( map int( rand 256 ), 1.. 3 ) );
    }
}
my $end = time;
printf "Filling a 1000x1000 pixel image 1-pixel at a time took: %.9fs\n", $end - $start;
#open O, '>:raw', 'junk.png'; print O $i->png; close O; system 1, 'junk.png';

my @cols;
$start = time;
for my $y ( 0 .. 999 ) {
    my @row;
    for my $x ( 0 .. 999 ) {
        push @row, [ $x, $y ];
    }
    push @cols, \@row;
}

my $Q = new Thread::Queue;
$Q->enqueue( \@cols );

async{ my $rCols = $Q->dequeue; }->join;

$end = time;
printf "Populating 1000x1000 AoAoAs and tranferring to another thread took: %.9fs\n", $end - $start;