diff --git a/xs/src/libslic3r/MultiPoint.cpp b/xs/src/libslic3r/MultiPoint.cpp
index 639eb6bb74..8b181d7bb3 100644
--- a/xs/src/libslic3r/MultiPoint.cpp
+++ b/xs/src/libslic3r/MultiPoint.cpp
@@ -130,24 +130,6 @@ MultiPoint::remove_duplicate_points()
     return false;
 }
 
-void
-MultiPoint::append(const Point &point)
-{
-    this->points.push_back(point);
-}
-
-void
-MultiPoint::append(const Points &points)
-{
-    this->append(points.begin(), points.end());
-}
-
-void
-MultiPoint::append(const Points::const_iterator &begin, const Points::const_iterator &end)
-{
-    this->points.insert(this->points.end(), begin, end);
-}
-
 bool
 MultiPoint::intersection(const Line& line, Point* intersection) const
 {
diff --git a/xs/src/libslic3r/MultiPoint.hpp b/xs/src/libslic3r/MultiPoint.hpp
index 60e24e17ea..0795e7a15b 100644
--- a/xs/src/libslic3r/MultiPoint.hpp
+++ b/xs/src/libslic3r/MultiPoint.hpp
@@ -18,7 +18,11 @@ class MultiPoint
     
     operator Points() const;
     MultiPoint() {};
-    explicit MultiPoint(const Points &_points): points(_points) {};
+    MultiPoint(const MultiPoint &other) : points(other.points) {}
+    MultiPoint(MultiPoint &&other) : points(std::move(other.points)) {}
+    explicit MultiPoint(const Points &_points): points(_points) {}
+    MultiPoint& operator=(const MultiPoint &other) { points = other.points; return *this; }
+    MultiPoint& operator=(MultiPoint &&other) { points = std::move(other.points); return *this; }
     void scale(double factor);
     void translate(double x, double y);
     void translate(const Point &vector);
@@ -38,9 +42,17 @@ class MultiPoint
     bool has_duplicate_points() const;
     // Remove exact duplicates, return true if any duplicate has been removed.
     bool remove_duplicate_points();
-    void append(const Point &point);
-    void append(const Points &points);
-    void append(const Points::const_iterator &begin, const Points::const_iterator &end);
+    void append(const Point &point) { this->points.push_back(point); }
+    void append(const Points &src) { this->append(src.begin(), src.end()); }
+    void append(const Points::const_iterator &begin, const Points::const_iterator &end) { this->points.insert(this->points.end(), begin, end); }
+    void append(Points &&src)
+    {
+        if (this->points.empty())
+            this->points = std::move(src);
+        else
+            std::move(std::begin(src), std::end(src), std::back_inserter(this->points));
+    }
+
     bool intersection(const Line& line, Point* intersection) const;
     std::string dump_perl() const;
     
diff --git a/xs/src/libslic3r/Point.cpp b/xs/src/libslic3r/Point.cpp
index 2ee5dabdd6..db90765d4d 100644
--- a/xs/src/libslic3r/Point.cpp
+++ b/xs/src/libslic3r/Point.cpp
@@ -174,14 +174,6 @@ Point::nearest_waypoint(const Points &points, const Point &dest, Point* point) c
     return true;
 }
 
-double
-Point::distance_to(const Point &point) const
-{
-    double dx = ((double)point.x - this->x);
-    double dy = ((double)point.y - this->y);
-    return sqrt(dx*dx + dy*dy);
-}
-
 /* distance to the closest point of line */
 double
 Point::distance_to(const Line &line) const
diff --git a/xs/src/libslic3r/Point.hpp b/xs/src/libslic3r/Point.hpp
index 0405ec0786..396d629a4b 100644
--- a/xs/src/libslic3r/Point.hpp
+++ b/xs/src/libslic3r/Point.hpp
@@ -54,7 +54,8 @@ class Point
     size_t nearest_waypoint_index(const Points &points, const Point &point) const;
     bool nearest_point(const Points &points, Point* point) const;
     bool nearest_waypoint(const Points &points, const Point &dest, Point* point) const;
-    double distance_to(const Point &point) const;
+    double distance_to(const Point &point) const { return sqrt(distance_to_sq(point)); }
+    double distance_to_sq(const Point &point) const { double dx = double(point.x - this->x); double dy = double(point.y - this->y); return dx*dx + dy*dy; }
     double distance_to(const Line &line) const;
     double perp_distance_to(const Line &line) const;
     double ccw(const Point &p1, const Point &p2) const;
diff --git a/xs/src/libslic3r/Polygon.hpp b/xs/src/libslic3r/Polygon.hpp
index b0a7ea40a0..7c8612d69b 100644
--- a/xs/src/libslic3r/Polygon.hpp
+++ b/xs/src/libslic3r/Polygon.hpp
@@ -14,14 +14,19 @@ class Polygon;
 typedef std::vector<Polygon> Polygons;
 
 class Polygon : public MultiPoint {
-    public:
+public:
     operator Polygons() const;
     operator Polyline() const;
     Point& operator[](Points::size_type idx);
     const Point& operator[](Points::size_type idx) const;
     
-    Polygon() {};
-    explicit Polygon(const Points &points): MultiPoint(points) {};
+    Polygon() {}
+    explicit Polygon(const Points &points): MultiPoint(points) {}
+    Polygon(const Polygon &other) : MultiPoint(other.points) {}
+    Polygon(Polygon &&other) : MultiPoint(std::move(other.points)) {}
+    Polygon& operator=(const Polygon &other) { points = other.points; return *this; }
+    Polygon& operator=(Polygon &&other) { points = std::move(other.points); return *this; }
+
     Point last_point() const;
     virtual Lines lines() const;
     Polyline split_at_vertex(const Point &point) const;
diff --git a/xs/src/libslic3r/Polyline.hpp b/xs/src/libslic3r/Polyline.hpp
index b8c04a12ad..007fcba62d 100644
--- a/xs/src/libslic3r/Polyline.hpp
+++ b/xs/src/libslic3r/Polyline.hpp
@@ -15,7 +15,36 @@ typedef std::vector<Polyline> Polylines;
 typedef std::vector<ThickPolyline> ThickPolylines;
 
 class Polyline : public MultiPoint {
-    public:
+public:
+    Polyline() {};
+    Polyline(const Polyline &other) : MultiPoint(other.points) {}
+    Polyline(Polyline &&other) : MultiPoint(std::move(other.points)) {}
+    Polyline& operator=(const Polyline &other) { points = other.points; return *this; }
+    Polyline& operator=(Polyline &&other) { points = std::move(other.points); return *this; }
+    
+    void append(const Point &point) { this->points.push_back(point); }
+    void append(const Points &src) { this->append(src.begin(), src.end()); }
+    void append(const Points::const_iterator &begin, const Points::const_iterator &end) { this->points.insert(this->points.end(), begin, end); }
+    void append(Points &&src)
+    {
+        if (this->points.empty())
+            this->points = std::move(src);
+        else
+            std::move(std::begin(src), std::end(src), std::back_inserter(this->points));
+    }
+    void append(const Polyline &src) 
+    { 
+        points.insert(points.end(), src.points.begin(), src.points.end());
+    }
+
+    void append(Polyline &&src) 
+    {
+        if (this->points.empty())
+            this->points = std::move(src.points);
+        else
+            std::move(std::begin(src.points), std::end(src.points), std::back_inserter(this->points));
+    }
+
     operator Polylines() const;
     operator Line() const;
     Point last_point() const;
@@ -63,6 +92,19 @@ inline Lines to_lines(const Polylines &polys)
     return lines;
 }
 
+inline void polylines_append(Polylines &dst, const Polylines &src) 
+{ 
+    dst.insert(dst.end(), src.begin(), src.end());
+}
+
+inline void polylines_append(Polylines &dst, Polylines &&src) 
+{
+    if (dst.empty())
+        dst = std::move(src);
+    else
+        std::move(std::begin(src), std::end(src), std::back_inserter(dst));
+}
+
 class ThickPolyline : public Polyline {
     public:
     std::vector<coordf_t> width;