It's probably a crazy idea but I've created a simple script for the Barnsley
Fern fractal. The script works but it brings my PC, an 2011 iMac, to it's
knees (OpenSCAD takes over 10Gb of memory with the script below and I want
to increase the number of objects even further). I was wondering if someone
has any suggestions to improve/optimize the script and make it less memory
hungry. Or is OpenSCAD not suitable for this kind of work. Thanks.

m1 = [[0,0],[0,0.16]];

c1 = [0,0];

m2 = [[0.85,0.04],[-0.04,0.85]];

c2 = [0, 0.16];

m3 = [[0.2,-0.26],[0.23,0.22]];

c3 = [0,1.6];

m4 = [[-0.15,0.28],[0.26,0.24]];

c4 = [0,0.44];

function f1(p) = m1 * p + c1;

function f2(p) = m2 * p + c2;

function f3(p) = m3 * p + c3;

function f4(p) = m4 * p + c4;

module plotCircle(p) {
translate(100 * p) circle(r=0.5,$fn=50);
}

module BarnsleyFern(p,index) {
r = rands(0,1,1)[0];
plotCircle(p);
if (r <= 0.01) {
BarnsleyFern(f1(p), index-1);
}
else if (r > 0.01 && r <=0.86) {
BarnsleyFern(f2(p),index-1);
}
else if (r > 0.86 && r <=0.94) {
BarnsleyFern(f3(p),index-1);
}
else if (r > 0.94 && r < 0.99) {
BarnsleyFern(f4(p),index-1);
}
}

p = [0,0];
BarnsleyFern(p,20000);

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That exact script takes less than a second for me and memory does
not grow over 350MB when running multiple times (using the latest
nightly build on Linux).

ciao,
Torsten.

Thanks Thorsten, I will try the latest development snapshot.

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You're right Torsten, I've tried the latest experimental build for OSX and it
makes a huge difference in memory. I've updated the code because I hadn't
been very thoughtful about the base case (see below for updated code). One
more thing. The recursive loop refuses to go beyond 1300 (or so). After that
I get the message: ERROR: Recursion detected calling module 'BarnsleyFern'
Any thoughts on that. Thanks guys.

m1 = [[0,0],[0,0.16]];

c1 = [0,0];

m2 = [[0.85,0.04],[-0.04,0.85]];

c2 = [0, 0.16];

m3 = [[0.2,-0.26],[0.23,0.22]];

c3 = [0,1.6];

m4 = [[-0.15,0.28],[0.26,0.24]];

c4 = [0,0.44];

function f1(p) = m1 * p + c1;

function f2(p) = m2 * p + c2;

function f3(p) = m3 * p + c3;

function f4(p) = m4 * p + c4;

module plotCircle(p) {
translate(100 * p) circle(r=0.5,$fn=50);
}

module BarnsleyFern(p,index) {
r = rands(0,1,1)[0];
plotCircle(p);
//echo(r,index);
if (r <= 0.01) {
BarnsleyFern(f1(p), index-1);
}
else if (r > 0.01 && r <=0.86) {
BarnsleyFern(f2(p),index-1);
}
else if (r > 0.86 && r <=0.94) {
BarnsleyFern(f3(p),index-1);
}
else if (index > 0) {
BarnsleyFern(f4(p),index-1);
}
}

p = [0,0];
BarnsleyFern(p,1400);

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Colin, thanks for your reply. I use P5.js (which is similar to Processing but
uses Javascript instead of Java) from time to time but it's just that I like
to 'torture' OpenSCAD to see where it's limits are ;-)

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