#!/usr/local/bin/ised --f
@0{0 3 1 2};   #! x to x+yf
@1{2 0 4 1};   #! y to fx-y
@2{2};         #! f to f
@3{3};         #! + to +
@4{4};         #! - to -
@10{$$$$$$$$$$$$$0}; #! 13 iterations

#! generating coordinates
@11{ {0 0 0 1 -1}_{$10\{0 1}} };#! 0 and 1 (x and y) are dropped as they don't represent movement. f is forward, + is left, - is right
@12(0 $11 -1);                  #! cumulative of angle changes gives absolute orientations
#! the same rules as for koch curve
@13(0 {1 0 -1 0}_$12 -1); #! x cumulative
@14(0 {0 1 0 -1}_$12 -1); #! y cumulative
--t '$13;$14'