Don't return first_point() and last_point() by reference

lib/Slic3r/GCode.pm

@@ -356,7 +356,7 @@ sub extrude_path {
         }
     }
     $gcode .= ";_BRIDGE_FAN_END\n" if $path->is_bridge;
-    $self->last_pos($path->last_point->clone);
+    $self->last_pos($path->last_point);
     
     if ($self->config->cooling) {
         my $path_time = $path_length / $F * 60;

lib/Slic3r/Layer/Region.pm

@@ -252,7 +252,7 @@ sub make_perimeters {
         # use a nearest neighbor search to order these children
         # TODO: supply second argument to chained_path_items() too?
         my @nodes = @{Slic3r::Geometry::chained_path_items(
-            [ map [ ($_->{outer} // $_->{hole})->first_point->clone, $_ ], @$polynodes ],
+            [ map [ ($_->{outer} // $_->{hole})->first_point, $_ ], @$polynodes ],
         )};
         
         my @loops = ();

xs/src/ExtrusionEntity.cpp

@@ -15,15 +15,15 @@ ExtrusionPath::reverse()
 }
 
 Point*
-ExtrusionPath::first_point()
+ExtrusionPath::first_point() const
 {
-    return &(this->polyline.points.front());
+    return new Point(this->polyline.points.front());
 }
 
 Point*
-ExtrusionPath::last_point()
+ExtrusionPath::last_point() const
 {
-    return &(this->polyline.points.back());
+    return new Point(this->polyline.points.back());
 }
 
 ExtrusionLoop*
@@ -66,15 +66,15 @@ ExtrusionLoop::reverse()
 }
 
 Point*
-ExtrusionLoop::first_point()
+ExtrusionLoop::first_point() const
 {
-    return &(this->polygon.points.front());
+    return new Point(this->polygon.points.front());
 }
 
 Point*
-ExtrusionLoop::last_point()
+ExtrusionLoop::last_point() const
 {
-    return &(this->polygon.points.front());  // in polygons, first == last
+    return new Point(this->polygon.points.front());  // in polygons, first == last
 }
 
 }

xs/src/ExtrusionEntity.hpp

@@ -31,8 +31,8 @@ class ExtrusionEntity
     double height;  // vertical thickness of the extrusion expressed in mm
     double flow_spacing;
     virtual void reverse() = 0;
-    virtual Point* first_point() = 0;
+    virtual Point* first_point() const = 0;
-    virtual Point* last_point() = 0;
+    virtual Point* last_point() const = 0;
 };
 
 typedef std::vector<ExtrusionEntity*> ExtrusionEntitiesPtr;
@@ -43,8 +43,8 @@ class ExtrusionPath : public ExtrusionEntity
     ExtrusionPath* clone() const;
     Polyline polyline;
     void reverse();
-    Point* first_point();
+    Point* first_point() const;
-    Point* last_point();
+    Point* last_point() const;
 };
 
 class ExtrusionLoop : public ExtrusionEntity
@@ -56,8 +56,8 @@ class ExtrusionLoop : public ExtrusionEntity
     ExtrusionPath* split_at_first_point();
     bool make_counter_clockwise();
     void reverse();
-    Point* first_point();
+    Point* first_point() const;
-    Point* last_point();
+    Point* last_point() const;
 };
 
 }

xs/src/ExtrusionEntityCollection.cpp

@@ -22,13 +22,13 @@ ExtrusionEntityCollection::reverse()
 }
 
 Point*
-ExtrusionEntityCollection::first_point()
+ExtrusionEntityCollection::first_point() const
 {
     return this->entities.front()->first_point();
 }
 
 Point*
-ExtrusionEntityCollection::last_point()
+ExtrusionEntityCollection::last_point() const
 {
     return this->entities.back()->last_point();
 }

xs/src/ExtrusionEntityCollection.hpp

@@ -16,8 +16,8 @@ class ExtrusionEntityCollection : public ExtrusionEntity
     ExtrusionEntityCollection* chained_path(bool no_reverse) const;
     ExtrusionEntityCollection* chained_path_from(Point* start_near, bool no_reverse) const;
     void reverse();
-    Point* first_point();
+    Point* first_point() const;
-    Point* last_point();
+    Point* last_point() const;
 };
 
 }

xs/src/MultiPoint.cpp

@@ -33,15 +33,9 @@ MultiPoint::reverse()
 }
 
 Point*
-MultiPoint::first_point()
-{
-    return &(this->points.front());
-}
-
-const Point*
 MultiPoint::first_point() const
 {
-    return &(this->points.front());
+    return new Point(this->points.front());
 }
 
 void

xs/src/MultiPoint.hpp

@@ -19,9 +19,8 @@ class MultiPoint
     void translate(double x, double y);
     void rotate(double angle, Point* center);
     void reverse();
-    Point* first_point();
+    Point* first_point() const;
-    const Point* first_point() const;
+    virtual Point* last_point() const = 0;
-    virtual Point* last_point() = 0;
 };
 
 }

xs/src/Polygon.cpp

@@ -6,9 +6,9 @@
 namespace Slic3r {
 
 Point*
-Polygon::last_point()
+Polygon::last_point() const
 {
-    return &(this->points.front());  // last point == first point for polygons
+    return new Point(this->points.front());  // last point == first point for polygons
 }
 
 SV*

xs/src/Polygon.hpp

@@ -11,7 +11,7 @@ namespace Slic3r {
 
 class Polygon : public MultiPoint {
     public:
-    Point* last_point();
+    Point* last_point() const;
     SV* to_SV_ref() const;
     SV* to_SV_clone_ref() const;
     Lines lines();

xs/src/Polyline.cpp

@@ -3,15 +3,9 @@
 namespace Slic3r {
 
 Point*
-Polyline::last_point()
-{
-    return &(this->points.back());
-}
-
-const Point*
 Polyline::last_point() const
 {
-    return &(this->points.back());
+    return new Point(this->points.back());
 }
 
 Lines

xs/src/Polyline.hpp

@@ -8,8 +8,7 @@ namespace Slic3r {
 
 class Polyline : public MultiPoint {
     public:
-    Point* last_point();
+    Point* last_point() const;
-    const Point* last_point() const;
     Lines lines();
     SV* to_SV_ref() const;
     SV* to_SV_clone_ref() const;