#/***********************************************************
#    koch.rb -- Koch (¥³¥Ã¥Û) ¶ÊÀþ
#***********************************************************/
require "plotter.rb"

PI = 3.141592653589793
DMAX = 0.005
$costbl = []
$sintbl = []


def koch
    if ($d <= DMAX)
        draw_rel($d * $costbl[$a % 6], $d * $sintbl[$a % 6])
    else 
        $d /= 3.0;  koch();  $a += 1;  koch()
        $a += 4;  koch();  $a += 1;  koch()
        $d *= 3
    end
end

gr_on
for $a in 0...6
    $costbl[$a] = Math::cos($a * PI / 3.0)
    $sintbl[$a] = Math::sin($a * PI / 3.0)
end
move(0, 0);  $d = 2;  $a = 0;  koch()
gr_off

exit 0