diff --git a/src/libslic3r/Fill/Lightning/Layer.cpp b/src/libslic3r/Fill/Lightning/Layer.cpp
index 1e1127a79..c996b9b7b 100644
--- a/src/libslic3r/Fill/Lightning/Layer.cpp
+++ b/src/libslic3r/Fill/Lightning/Layer.cpp
@@ -6,6 +6,7 @@
 #include "DistanceField.hpp"
 #include "TreeNode.hpp"
 
+#include "../../ClipperUtils.hpp"
 #include "../../Geometry.hpp"
 #include "Utils.hpp"
 
@@ -271,6 +272,7 @@ void Layer::reconnectRoots
     }
 }
 
+#if 0
 /*!
     * Moves the point \p from onto the nearest polygon or leaves the point as-is, when the comb boundary is not within the root of \p max_dist2 distance.
     * Given a \p distance more than zero, the point will end up inside, and conversely outside.
@@ -398,6 +400,7 @@ static unsigned int moveInside(const Polygons& polygons, Point& from, int distan
     }
     return static_cast<unsigned int>(-1);
 }
+#endif
 
 // Returns 'added someting'.
 Polylines Layer::convertToLines(const Polygons& limit_to_outline, const coord_t line_width) const
@@ -405,31 +408,11 @@ Polylines Layer::convertToLines(const Polygons& limit_to_outline, const coord_t
     if (tree_roots.empty())
         return {};
 
-    Polygons result_lines;
-    for (const auto& tree : tree_roots) {
-        // If even the furthest location in the tree is inside the polygon, the entire tree must be inside of the polygon.
-        // (Don't take the root as that may be on the edge and cause rounding errors to register as 'outside'.)
-        constexpr coord_t epsilon = 5;
-        Point should_be_inside = tree->getLocation();
-        moveInside(limit_to_outline, should_be_inside, epsilon, epsilon * epsilon);
-        if (inside(limit_to_outline, should_be_inside))
-            tree->convertToPolylines(result_lines, line_width);
-    }
+    Polylines result_lines;
+    for (const auto &tree : tree_roots)
+        tree->convertToPolylines(result_lines, line_width);
 
-    // TODO: allow for polylines!
-    Polylines split_lines;
-    for (Polygon &line : result_lines) {
-        if (line.size() <= 1)
-            continue;
-        Point last = line[0];
-        for (size_t point_idx = 1; point_idx < line.size(); point_idx++) {
-            Point here = line[point_idx];
-            split_lines.push_back({ last, here });
-            last = here;
-        }
-    }
-
-    return split_lines;
+    return intersection_pl(result_lines, limit_to_outline);
 }
 
 } // namespace Slic3r::Lightning
diff --git a/src/libslic3r/Fill/Lightning/TreeNode.cpp b/src/libslic3r/Fill/Lightning/TreeNode.cpp
index d1820410e..822550fc4 100644
--- a/src/libslic3r/Fill/Lightning/TreeNode.cpp
+++ b/src/libslic3r/Fill/Lightning/TreeNode.cpp
@@ -343,16 +343,16 @@ coord_t Node::prune(const coord_t& pruning_distance)
     return max_distance_pruned;
 }
 
-void Node::convertToPolylines(Polygons& output, const coord_t line_width) const
+void Node::convertToPolylines(Polylines &output, const coord_t line_width) const
 {
-    Polygons result;
+    Polylines result;
     result.emplace_back();
     convertToPolylines(0, result);
     removeJunctionOverlap(result, line_width);
     append(output, std::move(result));
 }
 
-void Node::convertToPolylines(size_t long_line_idx, Polygons& output) const
+void Node::convertToPolylines(size_t long_line_idx, Polylines &output) const
 {
     if (m_children.empty()) {
         output[long_line_idx].points.push_back(m_p);
@@ -372,12 +372,12 @@ void Node::convertToPolylines(size_t long_line_idx, Polygons& output) const
     }
 }
 
-void Node::removeJunctionOverlap(Polygons& result_lines, const coord_t line_width) const
+void Node::removeJunctionOverlap(Polylines &result_lines, const coord_t line_width) const
 {
     const coord_t reduction = line_width / 2; // TODO make configurable?
     size_t res_line_idx = 0;
     while (res_line_idx < result_lines.size()) {
-        Polygon &polyline = result_lines[res_line_idx];
+        Polyline &polyline = result_lines[res_line_idx];
         if (polyline.size() <= 1) {
             polyline = std::move(result_lines.back());
             result_lines.pop_back();
@@ -387,7 +387,7 @@ void Node::removeJunctionOverlap(Polygons& result_lines, const coord_t line_widt
         coord_t to_be_reduced = reduction;
         Point a = polyline.back();
         for (int point_idx = int(polyline.size()) - 2; point_idx >= 0; point_idx--) {
-            const Point b = polyline[point_idx];
+            const Point b = polyline.points[point_idx];
             const Point ab = b - a;
             const auto ab_len = coord_t(ab.cast<double>().norm());
             if (ab_len >= to_be_reduced) {
diff --git a/src/libslic3r/Fill/Lightning/TreeNode.hpp b/src/libslic3r/Fill/Lightning/TreeNode.hpp
index 55ef35e0a..fdb80d2e6 100644
--- a/src/libslic3r/Fill/Lightning/TreeNode.hpp
+++ b/src/libslic3r/Fill/Lightning/TreeNode.hpp
@@ -239,7 +239,7 @@ public:
      * 
      * \param output all branches in this tree connected into polylines
      */
-    void convertToPolylines(Polygons& output, coord_t line_width) const;
+    void convertToPolylines(Polylines &output, coord_t line_width) const;
 
     /*! If this was ever a direct child of the root, it'll have a previous grounding location.
      *
@@ -258,9 +258,9 @@ protected:
      * \param long_line a reference to a polyline in \p output which to continue building on in the recursion
      * \param output all branches in this tree connected into polylines
      */
-    void convertToPolylines(size_t long_line_idx, Polygons& output) const;
+    void convertToPolylines(size_t long_line_idx, Polylines &output) const;
 
-    void removeJunctionOverlap(Polygons& polylines, coord_t line_width) const;
+    void removeJunctionOverlap(Polylines &polylines, coord_t line_width) const;
 
     bool m_is_root;
     Point m_p;