From kragen@dnaco.net Sun Jul  5 17:54:41 1998
Date: Sun, 5 Jul 1998 17:54:40 -0400 (EDT)
From: Kragen <kragen@dnaco.net>
To: fractint@xmission.com
Subject: rep-tile L-systems
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I'm trying to write an L-system that will recursively subdivide a polygon
with copies of itself, a "rep-tile".  The particular rep-tile I'm trying
to do looks like this:

+-----+
|     |
|  +--+
|  |  |
+--+  +--+--+
|  |     |  |
|  +--+--+  |
|     |     |
+-----+-----+

(If that doesn't look like a polygon to you, maybe you're using a
variable-width font in your mailreader.  Switching to a fixed-width font
would help.)

I can't seem to figure out how to do it.  The closest I've got is this:

triangled {
        angle 8
        axiom +x
        x=x[@iq2f@q2x][-ff+++x][+ff---x]
        f=ff
}

This produces things in the right positions and orientations, but
they're not the right things, really, and some lines in the resulting
image get drawn numerous times.  It *is* interesting to look at, though.
(And it would make a hell of a city plan, too.  :)

(Same caveat: I haven't tested this with Fractint.)

Anyone have tips on how to do rep-tile L-systems?

btw, I came up with some more variations on the Koch snowflake I posted
yesterday, some of which are more visually interesting.  I'll post them
if anyone wants to look at them.

Kragen