#based on perl -MSDL::Tutorial::Drawing 
use strict;
use warnings;

use SDL::App;
use SDL::Rect;
use SDL::Color;

use vars::i '@iterative_set' => 
(

    sub {
        my @pt = ( 400, 50 );
        return( ( $pt[0] + $_[0] ) / 2, ( $pt[1] + $_[1] ) / 2 );
    },
    sub {
        my @pt = ( 50, 400 );
        return( ( $pt[0] + $_[0] ) / 2, ( $pt[1] + $_[1] ) / 2 );
    },
    sub {
        my @pt = ( 750, 400 );
        return( ( $pt[0] + $_[0] ) / 2, ( $pt[1] + $_[1] ) / 2 );
    },

);


# change these values as necessary
my $title                      = 'My SDL Rectangle-Drawing App';
my ($width, $height, $depth)   = ( 740,   640, 16   );
my ($red, $green, $blue)       = ( 0x00, 0x00, 0xff );
my ($rect_width, $rect_height) = ( 1,   1 );
my ($rect_x,     $rect_y)      = ( 270,   190       );

my $app = SDL::App->new(
	-width  => $width,
	-height => $height,
	-depth  => $depth,
);

my $color = SDL::Color->new(
	-r => $red,
	-g => $green,
	-b => $blue,
);
{
    # start coordinates
    my $x    = 40;
    my $y    = 400;
    my $iter = 0;
    
    # weed out transients
    while( $iter++ != 100 ) {
    
        ( $x, $y ) = $iterative_set[ int rand 3 ]->( $x, $y );
    
    }
    
    $iter = 0;
    while( $iter++ < 10000 ) {
        ( $x, $y ) = $iterative_set[ int rand 3 ]->( $x, $y );
        
        my $rect = SDL::Rect->new(
            -height => $rect_height,
            -width  => $rect_width,
            -x      => $x,
            -y      => $y,
        );
        $app->fill( $rect, $color );
        $app->update( $rect );
    
    }
}




# your code here; remove the next line

use SDL::Constants 'SDL_QUIT';
$app->loop({
SDL_QUIT() => sub { exit(0); },
});