diff --git a/src/libslic3r/PrintObject.cpp b/src/libslic3r/PrintObject.cpp index 1b593df26..85e70779c 100644 --- a/src/libslic3r/PrintObject.cpp +++ b/src/libslic3r/PrintObject.cpp @@ -1147,6 +1147,9 @@ void PrintObject::discover_vertical_shells() }; std::vector cache_top_botom_regions(num_layers, DiscoverVerticalShellsCacheEntry()); bool top_bottom_surfaces_all_regions = this->num_printing_regions() > 1 && ! m_config.interface_shells.value; +// static constexpr const float top_bottom_expansion_coeff = 1.05f; + // Just a tiny fraction of an infill extrusion width to merge neighbor regions reliably. + static constexpr const float top_bottom_expansion_coeff = 0.05f; if (top_bottom_surfaces_all_regions) { // This is a multi-material print and interface_shells are disabled, meaning that the vertical shell thickness // is calculated over all materials. @@ -1182,14 +1185,14 @@ void PrintObject::discover_vertical_shells() ++ debug_idx; #endif /* SLIC3R_DEBUG_SLICE_PROCESSING */ for (size_t region_id = 0; region_id < num_regions; ++ region_id) { - LayerRegion &layerm = *layer.m_regions[region_id]; - float min_perimeter_infill_spacing = float(layerm.flow(frSolidInfill).scaled_spacing()) * 1.05f; + LayerRegion &layerm = *layer.m_regions[region_id]; + float top_bottom_expansion = float(layerm.flow(frSolidInfill).scaled_spacing()) * top_bottom_expansion_coeff; // Top surfaces. - append(cache.top_surfaces, offset(layerm.slices().filter_by_type(stTop), min_perimeter_infill_spacing)); - append(cache.top_surfaces, offset(layerm.fill_surfaces().filter_by_type(stTop), min_perimeter_infill_spacing)); + append(cache.top_surfaces, offset(layerm.slices().filter_by_type(stTop), top_bottom_expansion)); +// append(cache.top_surfaces, offset(layerm.fill_surfaces().filter_by_type(stTop), top_bottom_expansion)); // Bottom surfaces. - append(cache.bottom_surfaces, offset(layerm.slices().filter_by_types(surfaces_bottom), min_perimeter_infill_spacing)); - append(cache.bottom_surfaces, offset(layerm.fill_surfaces().filter_by_types(surfaces_bottom), min_perimeter_infill_spacing)); + append(cache.bottom_surfaces, offset(layerm.slices().filter_by_types(surfaces_bottom), top_bottom_expansion)); +// append(cache.bottom_surfaces, offset(layerm.fill_surfaces().filter_by_types(surfaces_bottom), top_bottom_expansion)); // Calculate the maximum perimeter offset as if the slice was extruded with a single extruder only. // First find the maxium number of perimeters per region slice. unsigned int perimeters = 0; @@ -1252,16 +1255,16 @@ void PrintObject::discover_vertical_shells() const std::initializer_list surfaces_bottom { stBottom, stBottomBridge }; for (size_t idx_layer = range.begin(); idx_layer < range.end(); ++ idx_layer) { m_print->throw_if_canceled(); - Layer &layer = *m_layers[idx_layer]; - LayerRegion &layerm = *layer.m_regions[region_id]; - float min_perimeter_infill_spacing = float(layerm.flow(frSolidInfill).scaled_spacing()) * 1.05f; + Layer &layer = *m_layers[idx_layer]; + LayerRegion &layerm = *layer.m_regions[region_id]; + float top_bottom_expansion = float(layerm.flow(frSolidInfill).scaled_spacing()) * top_bottom_expansion_coeff; // Top surfaces. auto &cache = cache_top_botom_regions[idx_layer]; - cache.top_surfaces = offset(layerm.slices().filter_by_type(stTop), min_perimeter_infill_spacing); - append(cache.top_surfaces, offset(layerm.fill_surfaces().filter_by_type(stTop), min_perimeter_infill_spacing)); + cache.top_surfaces = offset(layerm.slices().filter_by_type(stTop), top_bottom_expansion); +// append(cache.top_surfaces, offset(layerm.fill_surfaces().filter_by_type(stTop), top_bottom_expansion)); // Bottom surfaces. - cache.bottom_surfaces = offset(layerm.slices().filter_by_types(surfaces_bottom), min_perimeter_infill_spacing); - append(cache.bottom_surfaces, offset(layerm.fill_surfaces().filter_by_types(surfaces_bottom), min_perimeter_infill_spacing)); + cache.bottom_surfaces = offset(layerm.slices().filter_by_types(surfaces_bottom), top_bottom_expansion); +// append(cache.bottom_surfaces, offset(layerm.fill_surfaces().filter_by_types(surfaces_bottom), top_bottom_expansion)); // Holes over all regions. Only collect them once, they are valid for all region_id iterations. if (cache.holes.empty()) { for (size_t region_id = 0; region_id < layer.regions().size(); ++ region_id) @@ -1437,9 +1440,24 @@ void PrintObject::discover_vertical_shells() Polygons shell_before = shell; #endif /* SLIC3R_DEBUG_SLICE_PROCESSING */ #if 1 - // Intentionally inflate a bit more than how much the region has been shrunk, - // so there will be some overlap between this solid infill and the other infill regions (mainly the sparse infill). - shell = opening(union_(shell), 0.5f * min_perimeter_infill_spacing, 0.8f * min_perimeter_infill_spacing, ClipperLib::jtSquare); + { + // Open to remove (filter out) regions narrower than a bit less than an infill extrusion line width. + // Such narrow regions are difficult to fill in with a gap fill algorithm (or Arachne), however they are most likely + // not needed for print stability / quality. + const float narrow_ensure_vertical_wall_thickness_region_radius = 0.5f * 0.65f * min_perimeter_infill_spacing; + // Then close gaps narrower than 1.2 * line width, such gaps are difficult to fill in with sparse infill, + // thus they will be merged into the solid infill. + const float narrow_sparse_infill_region_radius = 0.5f * 1.2f * min_perimeter_infill_spacing; + // Finally expand the infill a bit to remove tiny gaps between solid infill and the other regions. + const float tiny_overlap_radius = 0.2f * min_perimeter_infill_spacing; + shell = shrink(opening(union_(shell), + // Open to remove (filter out) regions narrower than an infill extrusion line width. + narrow_ensure_vertical_wall_thickness_region_radius, + // Then close gaps narrower than 1.2 * line width, such gaps are difficult to fill in with sparse infill. + narrow_ensure_vertical_wall_thickness_region_radius + narrow_sparse_infill_region_radius, ClipperLib::jtSquare), + // Finally expand the infill a bit to remove tiny gaps between solid infill and the other regions. + narrow_sparse_infill_region_radius - tiny_overlap_radius, ClipperLib::jtSquare); + } if (shell.empty()) continue; #else