From 04aa240265ea35d881dd5d395255bf9db23fcb52 Mon Sep 17 00:00:00 2001
From: Alessandro Ranellucci <aar@cpan.org>
Date: Tue, 13 Jan 2015 20:51:31 +0100
Subject: [PATCH] Only apply perimeter/infill overlap to the endpoints of
 rectilinear infill (and do that in a more proper way)

---
 lib/Slic3r/Fill.pm             |  2 +-
 lib/Slic3r/Fill/Concentric.pm  |  4 +---
 lib/Slic3r/Fill/Rectilinear.pm | 13 ++++++++++++-
 lib/Slic3r/Print/Object.pm     |  2 +-
 xs/xsp/Point.xsp               |  4 ++++
 5 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/lib/Slic3r/Fill.pm b/lib/Slic3r/Fill.pm
index 1881d461b..e3acbe551 100644
--- a/lib/Slic3r/Fill.pm
+++ b/lib/Slic3r/Fill.pm
@@ -142,7 +142,7 @@ sub make_fill {
     # we are going to grow such regions by overlapping them with the void (if any)
     # TODO: detect and investigate whether there could be narrow regions without
     # any void neighbors
-    my $distance_between_surfaces = $infill_flow->scaled_spacing * &Slic3r::INFILL_OVERLAP_OVER_SPACING;
+    my $distance_between_surfaces = $infill_flow->scaled_spacing;
     {
         my $collapsed = diff(
             [ map @{$_->expolygon}, @surfaces ],
diff --git a/lib/Slic3r/Fill/Concentric.pm b/lib/Slic3r/Fill/Concentric.pm
index 17f3fa225..1bc9b79f9 100644
--- a/lib/Slic3r/Fill/Concentric.pm
+++ b/lib/Slic3r/Fill/Concentric.pm
@@ -26,9 +26,7 @@ sub fill_surface {
         $self->spacing(unscale $distance);
     }
     
-    # compensate the overlap which is good for rectilinear but harmful for concentric
-    # where the perimeter/infill spacing should be equal to any other loop spacing
-    my @loops = my @last = @{offset(\@$expolygon, -&Slic3r::INFILL_OVERLAP_OVER_SPACING * $min_spacing / 2)};
+    my @loops = my @last = map $_->clone, @$expolygon;
     while (@last) {
         push @loops, @last = @{offset2(\@last, -($distance + 0.5*$min_spacing), +0.5*$min_spacing)};
     }
diff --git a/lib/Slic3r/Fill/Rectilinear.pm b/lib/Slic3r/Fill/Rectilinear.pm
index a50e12b09..b16b0bb0c 100644
--- a/lib/Slic3r/Fill/Rectilinear.pm
+++ b/lib/Slic3r/Fill/Rectilinear.pm
@@ -54,10 +54,21 @@ sub fill_surface {
     # the minimum offset for preventing edge lines from being clipped is scaled_epsilon;
     # however we use a larger offset to support expolygons with slightly skewed sides and 
     # not perfectly straight
-    my @polylines = @{intersection_pl(\@vertical_lines, $expolygon->offset(scale 0.02))};
+    my @polylines = @{intersection_pl(\@vertical_lines, $expolygon->offset(+scale 0.02))};
+    
+    my $extra = $self->_min_spacing * &Slic3r::INFILL_OVERLAP_OVER_SPACING;
+    foreach my $polyline (@polylines) {
+        my ($first_point, $last_point) = @$polyline[0,-1];
+        if ($first_point->y > $last_point->y) { #>
+            ($first_point, $last_point) = ($last_point, $first_point);
+        }
+        $first_point->set_y($first_point->y - $extra);  #--
+        $last_point->set_y($last_point->y + $extra);    #++
+    }
     
     # connect lines
     unless ($params{dont_connect} || !@polylines) {  # prevent calling leftmost_point() on empty collections
+        # offset the expolygon by max(min_spacing/2, extra)
         my ($expolygon_off) = @{$expolygon->offset_ex($self->_min_spacing/2)};
         my $collection = Slic3r::Polyline::Collection->new(@polylines);
         @polylines = ();
diff --git a/lib/Slic3r/Print/Object.pm b/lib/Slic3r/Print/Object.pm
index 93b69a0fa..4475e880f 100644
--- a/lib/Slic3r/Print/Object.pm
+++ b/lib/Slic3r/Print/Object.pm
@@ -1009,7 +1009,7 @@ sub combine_infill {
                      # Because fill areas for rectilinear and honeycomb are grown 
                      # later to overlap perimeters, we need to counteract that too.
                      + (($type == S_TYPE_INTERNALSOLID || $region->config->fill_pattern =~ /(rectilinear|honeycomb)/)
-                       ? $layerms[-1]->flow(FLOW_ROLE_SOLID_INFILL)->scaled_width * &Slic3r::INFILL_OVERLAP_OVER_SPACING
+                       ? $layerms[-1]->flow(FLOW_ROLE_SOLID_INFILL)->scaled_width
                        : 0)
                      )}, @$intersection;
 
diff --git a/xs/xsp/Point.xsp b/xs/xsp/Point.xsp
index 871911239..8386b146b 100644
--- a/xs/xsp/Point.xsp
+++ b/xs/xsp/Point.xsp
@@ -22,6 +22,10 @@
         %code{% RETVAL = THIS->x; %};
     long y()
         %code{% RETVAL = THIS->y; %};
+    void set_x(long val)
+        %code{% THIS->x = val; %};
+    void set_y(long val)
+        %code{% THIS->y = val; %};
     int nearest_point_index(Points points);
     Point* nearest_point(Points points)
         %code{% RETVAL = new Point(); THIS->nearest_point(points, RETVAL); %};