From 6454abfd5fbeb7140edcadee6a4b358e93fba35b Mon Sep 17 00:00:00 2001
From: DN <dn63@users.noreply.github.com>
Date: Wed, 4 Apr 2018 21:43:58 -0600
Subject: [PATCH] Raft pattern angles (#3001) (#4334)

Fixes #3001
---
 lib/Slic3r/Print/SupportMaterial.pm | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/Slic3r/Print/SupportMaterial.pm b/lib/Slic3r/Print/SupportMaterial.pm
index d3be45394..202d010e1 100644
--- a/lib/Slic3r/Print/SupportMaterial.pm
+++ b/lib/Slic3r/Print/SupportMaterial.pm
@@ -753,7 +753,9 @@ sub generate_toolpaths {
         
         # interface and contact infill
         if (@$interface || @$contact_infill) {
-            $fillers{interface}->set_angle(deg2rad($interface_angle));
+            # make interface layers alternate angles by 90 degrees
+            my $alternate_angle = $interface_angle + (90 * (($layer_id + 1) % 2));
+            $fillers{interface}->set_angle(deg2rad($alternate_angle));
             $fillers{interface}->set_min_spacing($_interface_flow->spacing);
             
             # find centerline of the external loop