Small memory optimization for some infills (#12063)

src/libslic3r/Fill/Fill3DHoneycomb.cpp

@@ -277,7 +277,7 @@ void Fill3DHoneycomb::_fill_surface_single(
     multiline_fill(polylines, params, spacing);
 
     // clip pattern to boundaries, chain the clipped polylines
-    polylines = intersection_pl(polylines, to_polygons(expolygon));
+    polylines = intersection_pl(std::move(polylines), to_polygons(expolygon));
 
     if (! polylines.empty()) {
     // Remove very small bits, but be careful to not remove infill lines connecting thin walls!

src/libslic3r/Fill/FillCrossHatch.cpp

@@ -208,7 +208,7 @@ void FillCrossHatch ::_fill_surface_single(
     // Apply multiline offset if needed
     multiline_fill(polylines, params, spacing);
 
-    polylines = intersection_pl(polylines, to_polygons(expolygon));
+    polylines = intersection_pl(std::move(polylines), to_polygons(expolygon));
 
     // --- remove small remains from gyroid infill
     if (!polylines.empty()) {

src/libslic3r/Fill/FillGyroid.cpp

@@ -187,7 +187,7 @@ void FillGyroid::_fill_surface_single(
     // Apply multiline offset if needed
     multiline_fill(polylines, params, spacing);
 
-	polylines = intersection_pl(polylines, expolygon);
+	polylines = intersection_pl(std::move(polylines), expolygon);
 
     if (! polylines.empty()) {
 		// Remove very small bits, but be careful to not remove infill lines connecting thin walls!

src/libslic3r/Fill/FillLine.cpp

@@ -58,7 +58,7 @@ void FillLine::_fill_surface_single(
         pts.push_back(it->a);
         pts.push_back(it->b);
     }
-    Polylines polylines = intersection_pl(polylines_src, offset(expolygon, scale_(0.02)));
+    Polylines polylines = intersection_pl(std::move(polylines_src), offset(expolygon, scale_(0.02)));
 
     // FIXME Vojtech: This is only performed for horizontal lines, not for the vertical lines!
     const float INFILL_OVERLAP_OVER_SPACING = 0.3f;

src/libslic3r/Fill/FillTpmsD.cpp

@@ -133,7 +133,7 @@ void FillTpmsD::_fill_surface_single(
 	    // Apply multiline offset if needed
     multiline_fill(polylines, params, spacing);
 
-	polylines = intersection_pl(polylines, expolygon);
+	polylines = intersection_pl(std::move(polylines), expolygon);
 
     if (! polylines.empty()) {
 		// Remove very small bits, but be careful to not remove infill lines connecting thin walls!