diff --git a/xs/lib/Slic3r/XS.pm b/xs/lib/Slic3r/XS.pm
index fb2649192..318cf7c7f 100644
--- a/xs/lib/Slic3r/XS.pm
+++ b/xs/lib/Slic3r/XS.pm
@@ -32,6 +32,11 @@ use overload
     '@{}' => sub { $_[0]->arrayref },
     'fallback' => 1;
 
+package Slic3r::Polyline::Ref;
+our @ISA = 'Slic3r::Polyline';
+
+sub DESTROY {}
+
 package Slic3r::Polyline::Collection;
 use overload
     '@{}' => sub { $_[0]->arrayref },
@@ -42,6 +47,11 @@ use overload
     '@{}' => sub { $_[0]->arrayref },
     'fallback' => 1;
 
+package Slic3r::Polygon::Ref;
+our @ISA = 'Slic3r::Polygon';
+
+sub DESTROY {}
+
 package Slic3r::ExPolygon::Collection;
 use overload
     '@{}' => sub { $_[0]->arrayref },
diff --git a/xs/t/07_extrusionpath.t b/xs/t/07_extrusionpath.t
index 835f25a21..78e084ccd 100644
--- a/xs/t/07_extrusionpath.t
+++ b/xs/t/07_extrusionpath.t
@@ -16,7 +16,7 @@ my $path = Slic3r::ExtrusionPath->new(
     polyline => Slic3r::Polyline->new(@$points),
     role     => Slic3r::ExtrusionPath::EXTR_ROLE_EXTERNAL_PERIMETER,
 );
-isa_ok $path->polyline, 'Slic3r::Polyline', 'path polyline';
+isa_ok $path->polyline, 'Slic3r::Polyline::Ref', 'path polyline';
 is_deeply $path->polyline->pp, $points, 'path points roundtrip';
 
 $path->reverse;
diff --git a/xs/t/08_extrusionloop.t b/xs/t/08_extrusionloop.t
index a218825f1..bd729361f 100644
--- a/xs/t/08_extrusionloop.t
+++ b/xs/t/08_extrusionloop.t
@@ -17,7 +17,7 @@ my $loop = Slic3r::ExtrusionLoop->new(
     polygon  => Slic3r::Polygon->new(@$square),
     role     => Slic3r::ExtrusionPath::EXTR_ROLE_EXTERNAL_PERIMETER,
 );
-isa_ok $loop->polygon, 'Slic3r::Polygon', 'loop polygon';
+isa_ok $loop->polygon, 'Slic3r::Polygon::Ref', 'loop polygon';
 is_deeply $loop->polygon->pp, $square, 'polygon points roundtrip';
 
 $loop = $loop->clone;
diff --git a/xs/t/12_extrusionpathcollection.t b/xs/t/12_extrusionpathcollection.t
index 176eac5c6..5d1704f0a 100644
--- a/xs/t/12_extrusionpathcollection.t
+++ b/xs/t/12_extrusionpathcollection.t
@@ -4,7 +4,7 @@ use strict;
 use warnings;
 
 use Slic3r::XS;
-use Test::More tests => 12;
+use Test::More tests => 13;
 
 my $points = [
     [100, 100],
@@ -35,12 +35,18 @@ is scalar(@$collection), 3, 'append ExtrusionPath';
 $collection->append($loop);
 is scalar(@$collection), 4, 'append ExtrusionLoop';
 
-isa_ok $collection->[1], 'Slic3r::ExtrusionPath::Collection', 'correct object returned for collection';
-isa_ok $collection->[2], 'Slic3r::ExtrusionPath', 'correct object returned for path';
-isa_ok $collection->[3], 'Slic3r::ExtrusionLoop', 'correct object returned for loop';
+isa_ok $collection->[1], 'Slic3r::ExtrusionPath::Collection::Ref', 'correct object returned for collection';
+isa_ok $collection->[2], 'Slic3r::ExtrusionPath::Ref', 'correct object returned for path';
+isa_ok $collection->[3], 'Slic3r::ExtrusionLoop::Ref', 'correct object returned for loop';
 
 is scalar(@{$collection->[1]}), 1, 'appended collection was duplicated';
 
+{
+    my $collection_loop = $collection->[3];
+    $collection_loop->polygon->scale(2);
+    is_deeply $collection->[3]->polygon->pp, $collection_loop->polygon->pp, 'items are returned by reference';
+}
+
 {
     my $collection = Slic3r::ExtrusionPath::Collection->new(
         map Slic3r::ExtrusionPath->new(polyline => $_, role => 0),
diff --git a/xs/xsp/ExtrusionLoop.xsp b/xs/xsp/ExtrusionLoop.xsp
index ecc117ef1..9c9249bf2 100644
--- a/xs/xsp/ExtrusionLoop.xsp
+++ b/xs/xsp/ExtrusionLoop.xsp
@@ -39,12 +39,12 @@ _new(CLASS, polygon_sv, role, height, flow_spacing)
 Polygon*
 ExtrusionLoop::polygon(...)
     PREINIT:
-        const char* CLASS = "Slic3r::Polygon";
+        const char* CLASS = "Slic3r::Polygon::Ref";
     CODE:
         if (items > 1) {
             THIS->polygon.from_SV_check( ST(1) );
         }
-        RETVAL = new Polygon(THIS->polygon);
+        RETVAL = &(THIS->polygon);
     OUTPUT:
         RETVAL
 
diff --git a/xs/xsp/ExtrusionPath.xsp b/xs/xsp/ExtrusionPath.xsp
index 7e52ac00c..9978e952e 100644
--- a/xs/xsp/ExtrusionPath.xsp
+++ b/xs/xsp/ExtrusionPath.xsp
@@ -41,12 +41,12 @@ _new(CLASS, polyline_sv, role, height, flow_spacing)
 Polyline*
 ExtrusionPath::polyline(...)
     PREINIT:
-        const char* CLASS = "Slic3r::Polyline";
+        const char* CLASS = "Slic3r::Polyline::Ref";
     CODE:
         if (items > 1) {
             THIS->polyline.from_SV_check( ST(1) );
         }
-        RETVAL = new Polyline(THIS->polyline);
+        RETVAL = &(THIS->polyline);
     OUTPUT:
         RETVAL