X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=treefoil.scad.pl;h=ee233a948661e66ebc82cdb80d4dc94ac8d059ec;hb=6dba99d4594590c1af949fbd0379d366a05c2ca6;hp=3bf401243ed1e162793bea0d94f09df8c80c832e;hpb=05430bd27f2161a1cfce3f1ddbfba28c20ee8eee;p=reprap-play.git

diff --git a/treefoil.scad.pl b/treefoil.scad.pl
old mode 100644
new mode 100755
index 3bf4012..ee233a9
--- a/treefoil.scad.pl
+++ b/treefoil.scad.pl
@@ -1,4 +1,75 @@
-__DATA__
+#!/usr/bin/perl -w
+
+# Use:
+#   - support X/Y dist 0.5mm
+
+use strict;
+
+our $shape = <<'END';
 xyyZZYYXYxxyzYYZXzzxyXXYXXXZxxxyyXXZyyyzXXzz
 zxxYYXXZXzzxyXXYZyyzxZZXZZZYzzzxxZZYxxxyZZyy
 yzzXXZZYZyyzxZZXYxxyzYYZYYYXyyyzzYYXzzzxYYxx
+END
+# simple version (unknotted, [0,1,2]^3):
+# YxxyzYYZXzzxyXXYZyyzxZZX
+
+sub o { print @_ or die $!; }
+
+o <<'END';
+// -*- autogenerated, do not edit -*-
+
+module Trace() {
+END
+
+my @p = qw(0 0 0);
+
+$"=',';
+
+while ($shape =~ s/^\s*(\w)//) {
+    my $ix = index('xyz', (lc $1));
+    my $sign = $1 =~ /[A-Z]/ ? +1 : -1;
+    my @q = @p;
+    $q[$ix] += $sign;
+    o "    TraceEdge([@p],[@q]);\n";
+    @p = @q;
+}
+
+die @p unless "@p" eq '0,0,0';
+
+o "}\n\n";
+
+while (<DATA>) { o $_ }
+
+__DATA__
+
+thick = 6;
+edgeu = 10;
+
+// calculated
+
+octa_long = thick;
+octa_short = octa_long / (1 + sqrt(2));
+
+module OctaThing() {
+    hull(){
+	for (r = [[0,0,0], [90,0,0], [0,90,0]]) {
+	    rotate(r)
+		cube([ octa_short,octa_short, octa_long ], center=true);
+	}
+    }
+}
+
+module TraceEdge(p,q) {
+    hull(){
+        for (x=[p,q]) {
+            translate(x * edgeu)
+                OctaThing();
+        }
+    }
+}
+
+rotate([0,0,45])
+  rotate([0,90,0])
+  Trace();
+
+