filter out tiny gaps

src/libslic3r/Fill/Fill.cpp

@@ -467,6 +467,7 @@ void Layer::make_fills(FillAdaptive::Octree* adaptive_fill_octree, FillAdaptive:
 		params.no_extrusion_overlap = surface_fill.params.overlap;
 
 		LayerRegion* layerm = this->m_regions[surface_fill.region_id];
+		params.config = &layerm->region().config();
 		for (ExPolygon& expoly : surface_fill.expolygons) {
 			f->no_overlap_expolygons = intersection_ex(layerm->fill_no_overlap_expolygons, ExPolygons() = { expoly });
 			// Spacing is modified by the filler to indicate adjustments. Reset it for each expolygon.

src/libslic3r/Fill/FillBase.hpp

@@ -74,6 +74,8 @@ struct FillParams
     bool            using_internal_flow{ false };
     //BBS: only used for new top surface pattern
     float           no_extrusion_overlap{ 0.0 };
+    const           PrintRegionConfig* config{ nullptr };
+
 };
 static_assert(IsTriviallyCopyable<FillParams>::value, "FillParams class is not POD (and it should be - see constructor).");
 

src/libslic3r/Fill/FillRectilinear.cpp

@@ -3169,9 +3169,17 @@ void FillMonotonicLineWGapFill::fill_surface_extrusion(const Surface* surface, c
         }
 
         if (!polylines.empty() && !is_bridge(params.extrusion_role)) {
+            if (!surface->is_top() && !surface->is_bottom()) {
+                polylines.erase(std::remove_if(polylines.begin(), polylines.end(),
+                    [&](const ThickPolyline& p) {
+                        return p.length() < scale_(params.config->filter_out_gap_fill.value);
+                    }), polylines.end());
+            }
+
             ExtrusionEntityCollection gap_fill;
             variable_width(polylines, erGapFill, params.flow, gap_fill.entities);
             coll_nosort->append(std::move(gap_fill.entities));
+
         }
     }