#!/usr/bin/env perl
#
# walls and water, or perhaps something like a terminal rug design
use 5.14.0;
use warnings;
use Game::TextPatterns;
use List::Util qw(min);
my $cols = 8;
my $rows = 8;
my $fill = rand(0.5) + 0.05;
my $field =
  Game::TextPatterns->new( pattern => "." )->multiply( $cols, $rows )
  ->white_noise( '#', $fill )->flip_four->four_up('.');
# water pattern is larger to produce some irregularity that may contrast
# with the walls
my $water =
  Game::TextPatterns->new( pattern => "." )->multiply( $cols + 2, $rows + 2 )
  ->flip_four->white_noise( '~', rand() / 4 + rand() / 4 )->four_up('.');
$field->mask( '.', $water );
# and these operations make the new field geometric with itself
$field->trim( min( $field->dimensions ) / 4 );
$field = $field->clone->four_up;
$field->trim( min( $field->dimensions ) / 4 );
$field = $field->clone->four_up;
$field->trim( min( $field->dimensions ) / 4 );
$field = $field->clone->four_up;
print $field->border( 1, '#' )->string;