diff --git a/xs/src/libslic3r/Point.hpp b/xs/src/libslic3r/Point.hpp
index 88b585307..b59100bfb 100644
--- a/xs/src/libslic3r/Point.hpp
+++ b/xs/src/libslic3r/Point.hpp
@@ -39,6 +39,7 @@ class Point
     };
     bool operator==(const Point& rhs) const { return this->x == rhs.x && this->y == rhs.y; }
     bool operator!=(const Point& rhs) const { return ! (*this == rhs); }
+    bool operator<(const Point& rhs) const { return this->x < rhs.x || (this->x == rhs.x && this->y < rhs.y); }
     std::string wkt() const;
     std::string dump_perl() const;
     void scale(double factor);