#!/usr/bin/perl -w
# dango0.pl - Don Yang (uguu.org)
#
# 12/08/07

use strict;
use constant WIDTH => 79;
use constant HEIGHT => 24;
use constant TIME_RES1 => 50;
use constant TIME_RES2 => 50;

my ($ax, $ay, $ah, $av1, $av2, $aex);
$ah = 23;
$av1 = 9.5;
$av2 = 5.5;
$aex = -2;

my $t = time() % (TIME_RES1 + TIME_RES2);

my $a = sin(2 * $t * atan2(0, -1) / (TIME_RES1 + TIME_RES2));
$ah = 20.5 - 3 * $a;
$av1 += 1.0 * $a;
$av2 -= 1.0 * $a;

if( $t < TIME_RES1 )
{
   $t /= TIME_RES1;
   $ax = 56 - 33 * $t;
   my $d = 2 * $t - 1;
   $ay = 10 + $d * $d * 8;
}
else
{
   $t = ($t - TIME_RES1) / TIME_RES2;
   $ax = 23 + 33 * $t;
   $ay = 18;
}

for(my $sy = 0; $sy < HEIGHT; $sy++)
{
   my $dya = ($sy - $ay) / ($sy < $ay ? $av1 : $av2);
   for(my $sx = 0; $sx < WIDTH; $sx++)
   {
      my $dxa = ($sx - $ax) / $ah;

      my $c = ' ';
      if( $dxa * $dxa + $dya * $dya <= 1 &&
          !($sy > $ay - 5 - 2 * $a && $sy <= $ay - 2 - 2 * $a &&
            ($sx == int($ax - 3 + $aex) || $sx == int($ax + 3 + $aex))) )
      {
         $c = 'X';
      }
      print $c;
   }
   print "\n";
}