Sierpinski square curve: Difference between revisions

=={{header|EasyLang}}==

[https://easylang.online/show/#cod=jVLRasMgFH33Kw4SxoZE0nYdjOFrviFQ+iCJXYVUg2Zt8vfDxiRN28Feop57zrl6chtnS6iukaZCrc6qBofstD0lcD+18sluD04AHKxDjdYOrIAAkCaBAKXxGDhlAm3gW1cepfPRK9YjRUNgBd+qBuvB0UzNZiYAfRhxvYdAmSyqsf+LmEhgWC0dVO3VH6I7N04etuPqL7IZQ5HmKuOEkyZEVzl5mWvf4IOq1kZddNUekfFNADoIbDN8oYfAOgvQyZ4VOvTkH8npQygL0JzO9+zABErrUWk3o31AvTZLNFxobHbNZXJMbxwr7SDwGpY0POcNJ1th85E9ythzGXsm42NkMajwDlbkLHwomeZMYAdaUNAiT3OWp5Ex7Cn2JM7p+/2Ektu/8JkR8gs= Run it]

<syntaxhighlight>

proc expand level . axiom$ rules$[] .

for l to level

an$ = ""

for c$ in strchars axiom$

for i = 1 step 2 to len rules$[]

if rules$[i] = c$

an$ &= rules$[i + 1]

else

an$ &= c$

.

.

.

swap axiom$ an$

.

.

proc draw axiom$ ang . .

linewidth 0.3

x = 50 ; y = 20

move x y

for c$ in strchars axiom$

if c$ = "F"

x += cos dir

y += sin dir

line x y

elif c$ = "-"

dir = (dir - ang) mod 360

elif c$ = "+"

dir = (dir + ang) mod 360

.

.

.

axiom$ = "F+XF+F+XF"

rules$[] = [ "X" "XF-F+F-XF+F+XF-F+F-X" ]

expand 4 axiom$ rules$[]

draw axiom$ 90

</syntaxhighlight>