From 59ab2fd29031c4d5930a44d7275347074a8746fb Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Sun, 7 Jan 2018 22:24:37 +0000
Subject: [PATCH] distort-stl: new approach, wip fixes

---
 distort-stl | 33 +++++++++++++++++++--------------
 1 file changed, 19 insertions(+), 14 deletions(-)

diff --git a/distort-stl b/distort-stl
index eb3a7a1..1b512f8 100755
--- a/distort-stl
+++ b/distort-stl
@@ -25,8 +25,11 @@
 use strict;
 use autodie;
 
-use File::Temp;
 use List::Util;
+use POSIX;
+use File::Temp ();
+
+sub TAU () { M_PI * 2; }
 
 our $fa = 10;
 
@@ -38,19 +41,19 @@ sub shift_arg () {
 }
 
 sub subdivide_triangle ($$) {
-    my ($it, $fn) = @_;
+    my ($t, $fn) = @_;
     my @mids;
     foreach my $ix (0..2) {
 	my $jx = ($ix+1) % 3;
 	my @midp;
 	foreach my $ci (0..2) {
-	    push @midp, 0.5 * ($it->[$ix][$ci] + $it->[$jx][$ci]);
+	    push @midp, 0.5 * ($t->[$ix][$ci] + $t->[$jx][$ci]);
 	}
 	push @mids, @midp;
     }
     foreach my $ix (0..2) {
 	my $kx = ($ix+2) % 3;
-	$fn->([ $it->[$ix], $mids[$ix], $it->[$kx] ]);
+	$fn->([ $t->[$ix], $mids[$ix], $t->[$kx] ]);
     }
     $fn->(\@mids);
 }
@@ -61,22 +64,22 @@ our $project_cylinder_radius;
 our $project_cylinder_max_d_theta;
 
 sub project_cylinder_tri {
-    my ($it) = @_;
+    my ($t) = @_;
 
-    my $radius = project_cylinder_radius;
+    my $radius = $project_cylinder_radius;
 
-    my @thetas = map { $_->[0] / $radius } @$it;
+    my @thetas = map { $_->[0] / $radius } @$t;
 
     foreach my $ix (0..2) {
 	if (abs($thetas[$ix] - $thetas[($ix+1)%3])
 	    > $project_cylinder_max_d_theta) {
-	    subdivide_triangle $it, \&project_cylinder_tri;
+	    subdivide_triangle $t, \&project_cylinder_tri;
 	    return;
 	}
     }
 
     my @ot;
-    foreach my $p (@it) {
+    foreach my $p ($t) {
 	my ($x,$y,$z) = @$p;
 	my $r = $radius - $y;
 	my $theta = $x / $radius;
@@ -115,19 +118,21 @@ open I, "admesh $admesh_stdout $itmp |";
 my $triangle;
 
 while (<I>) {
-    if (m/^\s+outer\s+loop/) {
+    s/^\s*//;
+    if (m/^outer\s+loop/) {
 	die if $triangle;
 	$triangle = [];
-    } elsif (s/^\s+vertex\s+//) {
+    } elsif (s/^vertex\s+//) {
 	my $lhs = $&;
 	s/\s+$//;
 	my @xyz = split /\s+/, $_;
 	die unless $triangle;
-	push @$triangle, \@xya;
-    } elsif (m/^\s+endloop/) {
+	push @$triangle, \@xyz;
+    } elsif (m/^endloop/) {
 	die unless @$triangle == 3;
 	push @triangles, $triangle;
-    } elsif (m/^\s+(?:solid|facet\s+normal|endfacet|endsolid)\s/) {
+	undef $triangle;
+    } elsif (m/^(?:solid|facet\s+normal|endfacet|endsolid)\s/) {
     } else {
 	die "$_ ?";
     }
-- 
2.30.2