From c3dde7477614faeff7dbc6995c458634f8ac840e Mon Sep 17 00:00:00 2001
From: Alessandro Ranellucci <aar@cpan.org>
Date: Sun, 24 Feb 2013 16:40:14 +0100
Subject: [PATCH] Fix brim and extra perimeters after recent changes to
 ->slices

---
 lib/Slic3r/Print.pm        |  2 +-
 lib/Slic3r/Print/Object.pm | 18 +++++++++---------
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/lib/Slic3r/Print.pm b/lib/Slic3r/Print.pm
index 322b8fa48..8676cd219 100644
--- a/lib/Slic3r/Print.pm
+++ b/lib/Slic3r/Print.pm
@@ -635,7 +635,7 @@ sub make_brim {
             polygon         => Slic3r::Polygon->new($_),
             role            => EXTR_ROLE_SKIRT,
             flow_spacing    => $flow->spacing,
-        ) for Slic3r::Geometry::Clipper::offset(\@islands, $i * $flow->scaled_spacing, undef, JT_SQUARE);
+        ) for Slic3r::Geometry::Clipper::offset(\@islands, ($i - 0.5) * $flow->scaled_spacing, undef, JT_SQUARE); # -0.5 because islands are not represented by their centerlines
         # TODO: we need the offset inwards/offset outwards logic to avoid overlapping extrusions
     }
 }
diff --git a/lib/Slic3r/Print/Object.pm b/lib/Slic3r/Print/Object.pm
index 638482fbc..c33660230 100644
--- a/lib/Slic3r/Print/Object.pm
+++ b/lib/Slic3r/Print/Object.pm
@@ -208,15 +208,15 @@ sub make_perimeters {
             for my $layer_id (0 .. $self->layer_count-2) {
                 my $layerm          = $self->layers->[$layer_id]->regions->[$region_id];
                 my $upper_layerm    = $self->layers->[$layer_id+1]->regions->[$region_id];
-                my $perimeter_flow  = $layerm->perimeter_flow;
+                my $perimeter_spacing       = $layerm->perimeter_flow->scaled_spacing;
                 
-                my $overlap = $perimeter_flow->scaled_spacing;  # one perimeter
+                my $overlap = $perimeter_spacing;  # one perimeter
                 
                 # compute polygons representing the thickness of the first external perimeter of
                 # the upper layer slices
                 my $upper = diff_ex(
-                    [ map @$_, map $_->expolygon->offset_ex(+ 0.5 * $perimeter_flow->scaled_spacing), @{$upper_layerm->slices} ],
-                    [ map @$_, map $_->expolygon->offset_ex(- $overlap + (0.5 * $perimeter_flow->scaled_spacing)), @{$upper_layerm->slices} ],
+                    [ map @{$_->expolygon}, @{$upper_layerm->slices} ],
+                    [ map @$_, map $_->expolygon->offset_ex(-$overlap), @{$upper_layerm->slices} ],
                 );
                 next if !@$upper;
                 
@@ -225,10 +225,10 @@ sub make_perimeters {
                 my $ignore = [];
                 {
                     my $diff = diff_ex(
-                        [ map @$_, map $_->expolygon->offset_ex(- ($Slic3r::Config->perimeters-0.5) * $perimeter_flow->scaled_spacing), @{$layerm->slices} ],
-                        [ map @{$_->expolygon}, @{$upper_layerm->slices} ],
+                        [ map @$_, map $_->expolygon->offset_ex(- $Slic3r::Config->perimeters * $perimeter_spacing), @{$layerm->slices} ],
+                        [ map @$_, map $_->expolygon->offset_ex(- 0.5*$perimeter_spacing), @{$upper_layerm->slices} ],
                     );
-                    $ignore = [ map @$_, map $_->offset_ex($perimeter_flow->scaled_spacing), @$diff ];
+                    $ignore = [ map @$_, map $_->offset_ex($perimeter_spacing), @$diff ];
                 }
                 
                 foreach my $slice (@{$layerm->slices}) {
@@ -238,9 +238,9 @@ sub make_perimeters {
                         # of our slice
                         my $hypothetical_perimeter;
                         {
-                            my $outer = [ map @$_, $slice->expolygon->offset_ex(- ($hypothetical_perimeter_num-1.5) * $perimeter_flow->scaled_spacing - scaled_epsilon) ];
+                            my $outer = [ map @$_, $slice->expolygon->offset_ex(- ($hypothetical_perimeter_num-1) * $perimeter_spacing - scaled_epsilon) ];
                             last CYCLE if !@$outer;
-                            my $inner = [ map @$_, $slice->expolygon->offset_ex(- ($hypothetical_perimeter_num-0.5) * $perimeter_flow->scaled_spacing) ];
+                            my $inner = [ map @$_, $slice->expolygon->offset_ex(- $hypothetical_perimeter_num * $perimeter_spacing) ];
                             last CYCLE if !@$inner;
                             $hypothetical_perimeter = diff_ex($outer, $inner);
                         }