From 94e673e0508999830b14f8509cba257de0d38ce4 Mon Sep 17 00:00:00 2001
From: Alessandro Ranellucci <aar@cpan.org>
Date: Fri, 24 Feb 2012 23:12:16 +0100
Subject: [PATCH] Backwards compatibility for people using relative E distances
 on RepRap firmwares

---
 lib/Slic3r/Print.pm | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/lib/Slic3r/Print.pm b/lib/Slic3r/Print.pm
index 03da5dd2f..3a1101131 100644
--- a/lib/Slic3r/Print.pm
+++ b/lib/Slic3r/Print.pm
@@ -547,8 +547,12 @@ sub export_gcode {
     print  $fh "G21 ; set units to millimeters\n";
     if ($Slic3r::gcode_flavor =~ /^(?:reprap|teacup|makerbot)$/) {
         printf $fh "G92 %s0 ; reset extrusion distance\n", $Slic3r::extrusion_axis;
-        if (!$Slic3r::use_relative_e_distances && $Slic3r::gcode_flavor =~ /^(?:reprap|makerbot)$/) {
-            print $fh "M82 ; use absolute distances for extrusion\n";
+        if ($Slic3r::gcode_flavor =~ /^(?:reprap|makerbot)$/) {
+            if ($Slic3r::use_relative_e_distances) {
+                print $fh "M83 ; use relative distances for extrusion\n";
+            } else {
+                print $fh "M82 ; use absolute distances for extrusion\n";
+            }
         }
     }