From abb8e254760ea536a17c97cc78191c1cc6403a93 Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Sun, 7 Jan 2018 20:21:44 +0000
Subject: [PATCH] distort-stl: works now but needs to do something about lines

---
 distort-stl | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/distort-stl b/distort-stl
index da9b4ae..4820e03 100755
--- a/distort-stl
+++ b/distort-stl
@@ -29,13 +29,13 @@ sub shift_arg () {
     scalar shift @ARGV;
 }
 
-sub pointmap_distortion {
+sub pointmap_project_cylinder {
     my ($x,$y,$z) = @_;
     my $radius = shift_arg;
-    my $r = $y + $radius;
+    my $r = $radius - $y;
     my $theta = $x / $radius;
-    return ($r * cos($theta),
-	    $r * sin($theta),
+    return ($r * sin($theta),
+	    -$r * cos($theta),
 	    $z);
 }
 
@@ -62,7 +62,8 @@ while (<I>) {
 	my @xyz = split /\s+/, $_;
 	while (@ARGV) {
 	    my $op = shift_arg;
-	    @xyz = &{ $::{"pointmap_$op"} }( @xyz );
+	    $op =~ y/-/_/;
+	    @xyz = &{ ${*::}{"pointmap_$op"} }( @xyz );
 	}
 	@xyz = map { sprintf "%.18g", $_ } @xyz;
 	$_ = "$lhs@xyz\n";
-- 
2.30.2