From 0c22250740986a702cdf3d9d19db51ca423ce1bd Mon Sep 17 00:00:00 2001
From: Alessandro Ranellucci <aar@cpan.org>
Date: Sat, 25 Aug 2012 16:30:11 +0200
Subject: [PATCH] New option to disable retraction when moving between infill
 paths inside the same island. #29

---
 README.markdown       |  3 +++
 lib/Slic3r/Config.pm  |  7 +++++++
 lib/Slic3r/GCode.pm   | 14 ++++++--------
 lib/Slic3r/GUI/Tab.pm |  2 +-
 slic3r.pl             |  3 +++
 5 files changed, 20 insertions(+), 9 deletions(-)

diff --git a/README.markdown b/README.markdown
index a335f0cb..46c779a8 100644
--- a/README.markdown
+++ b/README.markdown
@@ -170,6 +170,9 @@ The author of the Silk icon set is Mark James.
         --layer-gcode       Load layer-change G-code from the supplied file (default: nothing).
         --extra-perimeters  Add more perimeters when needed (default: yes)
         --randomize-start   Randomize starting point across layers (default: yes)
+        --only-retract-when-crossing-perimeters
+                            Disable retraction when travelling between infill paths inside the same island.
+                            (default: no)
         --solid-infill-below-area
                             Force solid infill when a region has a smaller area than this threshold
                             (mm^2, default: 70)
diff --git a/lib/Slic3r/Config.pm b/lib/Slic3r/Config.pm
index 36aaa5ae..97992d5b 100644
--- a/lib/Slic3r/Config.pm
+++ b/lib/Slic3r/Config.pm
@@ -470,6 +470,13 @@ our $Options = {
         type    => 'bool',
         default => 1,
     },
+    'only_retract_when_crossing_perimeters' => {
+        label   => 'Only retract when crossing perimeters',
+        tooltip => 'Disables retraction when travelling between infill paths inside the same island.',
+        cli     => 'only-retract-when-crossing-perimeters!',
+        type    => 'bool',
+        default => 0,
+    },
     'support_material' => {
         label   => 'Generate support material',
         tooltip => 'Enable support material generation.',
diff --git a/lib/Slic3r/GCode.pm b/lib/Slic3r/GCode.pm
index b5e020ac..ae6d63c6 100644
--- a/lib/Slic3r/GCode.pm
+++ b/lib/Slic3r/GCode.pm
@@ -132,15 +132,13 @@ sub extrude_path {
     my $gcode = "";
     
     # retract if distance from previous position is greater or equal to the one
-    # specified by the user *and* to the maximum distance between infill lines
+    # specified by the user
     {
-        my $distance_from_last_pos = $self->last_pos->distance_to($path->points->[0]) * &Slic3r::SCALING_FACTOR;
-        my $distance_threshold = $self->extruder->retract_before_travel;
-        $distance_threshold = 2 * ($self->layer ? $self->layer->flow->width : $Slic3r::flow->width) / $Slic3r::Config->fill_density * sqrt(2)
-            if 0 && $Slic3r::Config->fill_density > 0 && $description =~ /fill/;
-    
-        if ($distance_from_last_pos >= $distance_threshold) {
-            $gcode .= $self->retract(travel_to => $path->points->[0]);
+        my $travel = Slic3r::Line->new($self->last_pos, $path->points->[0]);
+        if ($travel->length >= scale $self->extruder->retract_before_travel) {
+            if (!$Slic3r::Config->only_retract_when_crossing_perimeters || $path->role != EXTR_ROLE_FILL || !first { $_->expolygon->encloses_line($travel) } @{$self->layer->slices}) {
+                $gcode .= $self->retract(travel_to => $path->points->[0]);
+            }
         }
     }
     
diff --git a/lib/Slic3r/GUI/Tab.pm b/lib/Slic3r/GUI/Tab.pm
index cd68593a..16107b54 100644
--- a/lib/Slic3r/GUI/Tab.pm
+++ b/lib/Slic3r/GUI/Tab.pm
@@ -401,7 +401,7 @@ sub build {
         },
         {
             title => 'Advanced',
-            options => [qw(infill_every_layers fill_angle solid_infill_below_area)],
+            options => [qw(infill_every_layers fill_angle solid_infill_below_area only_retract_when_crossing_perimeters)],
         },
     ]);
     
diff --git a/slic3r.pl b/slic3r.pl
index 0f9baa58..2e9c8707 100755
--- a/slic3r.pl
+++ b/slic3r.pl
@@ -213,6 +213,9 @@ $j
     --layer-gcode       Load layer-change G-code from the supplied file (default: nothing).
     --extra-perimeters  Add more perimeters when needed (default: yes)
     --randomize-start   Randomize starting point across layers (default: yes)
+    --only-retract-when-crossing-perimeters
+                        Disable retraction when travelling between infill paths inside the same island.
+                        (default: no)
     --solid-infill-below-area
                         Force solid infill when a region has a smaller area than this threshold
                         (mm^2, default: $config->{solid_infill_below_area})