diff --git a/src/libslic3r/Fill/Fill.cpp b/src/libslic3r/Fill/Fill.cpp
index b582be3b002..c85c69e8e56 100644
--- a/src/libslic3r/Fill/Fill.cpp
+++ b/src/libslic3r/Fill/Fill.cpp
@@ -9805,9 +9805,9 @@ static bool top_surface_image_append_recolored_perimeter_path(ExtrusionEntitiesP
     };
 
     for (size_t point_idx = 1; point_idx < path.polyline.points.size(); ++point_idx) {
-        const Point &p0 = path.polyline.points[point_idx - 1];
-        const Point &p1 = path.polyline.points[point_idx];
-        const double len_mm = unscale<double>(p0.distance_to(p1));
+        const Point3 &p0 = path.polyline.points[point_idx - 1];
+        const Point3 &p1 = path.polyline.points[point_idx];
+        const double len_mm = unscale<double>(p0.to_point().distance_to(p1.to_point()));
         if (!std::isfinite(len_mm) || len_mm <= EPSILON)
             continue;
         const int steps = std::max(1, int(std::floor(len_mm / min_run_mm)));
diff --git a/src/libslic3r/Polyline.hpp b/src/libslic3r/Polyline.hpp
index 88671391db9..c14d6329e94 100644
--- a/src/libslic3r/Polyline.hpp
+++ b/src/libslic3r/Polyline.hpp
@@ -302,6 +302,8 @@ public:
 
     virtual Lines3 lines() const;
 
+    bool is_closed() const { return this->points.size() >= 2 && this->points.front() == this->points.back(); }
+
     // Convert to 2D Polyline by dropping Z coordinates
     Polyline to_polyline() const;