diff --git a/xs/src/libslic3r/TriangleMesh.cpp b/xs/src/libslic3r/TriangleMesh.cpp index 83cf0fa88..544a5d00b 100644 --- a/xs/src/libslic3r/TriangleMesh.cpp +++ b/xs/src/libslic3r/TriangleMesh.cpp @@ -1,6 +1,7 @@ #include "TriangleMesh.hpp" #include "ClipperUtils.hpp" #include "Geometry.hpp" +#include "MultiPoint.hpp" #include "qhull/src/libqhullcpp/Qhull.h" #include "qhull/src/libqhullcpp/QhullFacetList.h" #include "qhull/src/libqhullcpp/QhullVertexSet.h" @@ -1232,6 +1233,344 @@ static inline void remove_tangent_edges(std::vector &lines) } } +struct OpenPolyline { + OpenPolyline() {}; + OpenPolyline(const IntersectionReference &start, const IntersectionReference &end, Points &&points) : + start(start), end(end), points(std::move(points)), consumed(false) { this->length = Slic3r::length(this->points); } + void reverse() { + std::swap(start, end); + std::reverse(points.begin(), points.end()); + } + IntersectionReference start; + IntersectionReference end; + Points points; + double length; + bool consumed; +}; + +// called by TriangleMeshSlicer::make_loops() to connect sliced triangles into closed loops and open polylines by the triangle connectivity. +// Only connects segments crossing triangles of the same orientation. +static void chain_lines_by_triangle_connectivity(std::vector &lines, Polygons &loops, std::vector &open_polylines) +{ + // Build a map of lines by edge_a_id and a_id. + std::vector by_edge_a_id; + std::vector by_a_id; + by_edge_a_id.reserve(lines.size()); + by_a_id.reserve(lines.size()); + for (IntersectionLine &line : lines) { + if (! line.skip()) { + if (line.edge_a_id != -1) + by_edge_a_id.emplace_back(&line); + if (line.a_id != -1) + by_a_id.emplace_back(&line); + } + } + auto by_edge_lower = [](const IntersectionLine* il1, const IntersectionLine *il2) { return il1->edge_a_id < il2->edge_a_id; }; + auto by_vertex_lower = [](const IntersectionLine* il1, const IntersectionLine *il2) { return il1->a_id < il2->a_id; }; + std::sort(by_edge_a_id.begin(), by_edge_a_id.end(), by_edge_lower); + std::sort(by_a_id.begin(), by_a_id.end(), by_vertex_lower); + // Chain the segments with a greedy algorithm, collect the loops and unclosed polylines. + IntersectionLines::iterator it_line_seed = lines.begin(); + for (;;) { + // take first spare line and start a new loop + IntersectionLine *first_line = nullptr; + for (; it_line_seed != lines.end(); ++ it_line_seed) + if (it_line_seed->is_seed_candidate()) { + //if (! it_line_seed->skip()) { + first_line = &(*it_line_seed ++); + break; + } + if (first_line == nullptr) + break; + first_line->set_skip(); + Points loop_pts; + loop_pts.emplace_back(first_line->a); + IntersectionLine *last_line = first_line; + + /* + printf("first_line edge_a_id = %d, edge_b_id = %d, a_id = %d, b_id = %d, a = %d,%d, b = %d,%d\n", + first_line->edge_a_id, first_line->edge_b_id, first_line->a_id, first_line->b_id, + first_line->a.x, first_line->a.y, first_line->b.x, first_line->b.y); + */ + + IntersectionLine key; + for (;;) { + // find a line starting where last one finishes + IntersectionLine* next_line = nullptr; + if (last_line->edge_b_id != -1) { + key.edge_a_id = last_line->edge_b_id; + auto it_begin = std::lower_bound(by_edge_a_id.begin(), by_edge_a_id.end(), &key, by_edge_lower); + if (it_begin != by_edge_a_id.end()) { + auto it_end = std::upper_bound(it_begin, by_edge_a_id.end(), &key, by_edge_lower); + for (auto it_line = it_begin; it_line != it_end; ++ it_line) + if (! (*it_line)->skip()) { + next_line = *it_line; + break; + } + } + } + if (next_line == nullptr && last_line->b_id != -1) { + key.a_id = last_line->b_id; + auto it_begin = std::lower_bound(by_a_id.begin(), by_a_id.end(), &key, by_vertex_lower); + if (it_begin != by_a_id.end()) { + auto it_end = std::upper_bound(it_begin, by_a_id.end(), &key, by_vertex_lower); + for (auto it_line = it_begin; it_line != it_end; ++ it_line) + if (! (*it_line)->skip()) { + next_line = *it_line; + break; + } + } + } + if (next_line == nullptr) { + // Check whether we closed this loop. + if ((first_line->edge_a_id != -1 && first_line->edge_a_id == last_line->edge_b_id) || + (first_line->a_id != -1 && first_line->a_id == last_line->b_id)) { + // The current loop is complete. Add it to the output. + loops.emplace_back(std::move(loop_pts)); + #ifdef SLIC3R_TRIANGLEMESH_DEBUG + printf(" Discovered %s polygon of %d points\n", (p.is_counter_clockwise() ? "ccw" : "cw"), (int)p.points.size()); + #endif + } else { + // This is an open polyline. Add it to the list of open polylines. These open polylines will processed later. + loop_pts.emplace_back(last_line->b); + open_polylines.emplace_back(OpenPolyline( + IntersectionReference(first_line->a_id, first_line->edge_a_id), + IntersectionReference(last_line->b_id, last_line->edge_b_id), std::move(loop_pts))); + } + break; + } + /* + printf("next_line edge_a_id = %d, edge_b_id = %d, a_id = %d, b_id = %d, a = %d,%d, b = %d,%d\n", + next_line->edge_a_id, next_line->edge_b_id, next_line->a_id, next_line->b_id, + next_line->a.x, next_line->a.y, next_line->b.x, next_line->b.y); + */ + loop_pts.emplace_back(next_line->a); + last_line = next_line; + next_line->set_skip(); + } + } +} + +std::vector open_polylines_sorted(std::vector &open_polylines, bool update_lengths) +{ + std::vector out; + out.reserve(open_polylines.size()); + for (OpenPolyline &opl : open_polylines) + if (! opl.consumed) { + if (update_lengths) + opl.length = Slic3r::length(opl.points); + out.emplace_back(&opl); + } + std::sort(out.begin(), out.end(), [](const OpenPolyline *lhs, const OpenPolyline *rhs){ return lhs->length > rhs->length; }); + return out; +} + +// called by TriangleMeshSlicer::make_loops() to connect remaining open polylines across shared triangle edges and vertices. +// Depending on "try_connect_reversed", it may or may not connect segments crossing triangles of opposite orientation. +static void chain_open_polylines_exact(std::vector &open_polylines, Polygons &loops, bool try_connect_reversed) +{ + // Store the end points of open_polylines into vectors sorted + struct OpenPolylineEnd { + OpenPolylineEnd(OpenPolyline *polyline, bool start) : polyline(polyline), start(start) {} + OpenPolyline *polyline; + // Is it the start or end point? + bool start; + const IntersectionReference& ipref() const { return start ? polyline->start : polyline->end; } + // Return a unique ID for the intersection point. + // Return a positive id for a point, or a negative id for an edge. + int id() const { const IntersectionReference &r = ipref(); return (r.point_id >= 0) ? r.point_id : - r.edge_id; } + bool operator==(const OpenPolylineEnd &rhs) const { return this->polyline == rhs.polyline && this->start == rhs.start; } + }; + auto by_id_lower = [](const OpenPolylineEnd &ope1, const OpenPolylineEnd &ope2) { return ope1.id() < ope2.id(); }; + std::vector by_id; + by_id.reserve(2 * open_polylines.size()); + for (OpenPolyline &opl : open_polylines) { + if (opl.start.point_id != -1 || opl.start.edge_id != -1) + by_id.emplace_back(OpenPolylineEnd(&opl, true)); + if (try_connect_reversed && (opl.end.point_id != -1 || opl.end.edge_id != -1)) + by_id.emplace_back(OpenPolylineEnd(&opl, false)); + } + std::sort(by_id.begin(), by_id.end(), by_id_lower); + // Find an iterator to by_id_lower for the particular end of OpenPolyline (by comparing the OpenPolyline pointer and the start attribute). + auto find_polyline_end = [&by_id, by_id_lower](const OpenPolylineEnd &end) -> std::vector::iterator { + for (auto it = std::lower_bound(by_id.begin(), by_id.end(), end, by_id_lower); + it != by_id.end() && it->id() == end.id(); ++ it) + if (*it == end) + return it; + return by_id.end(); + }; + // Try to connect the loops. + std::vector sorted_by_length = open_polylines_sorted(open_polylines, false); + for (OpenPolyline *opl : sorted_by_length) { + if (opl->consumed) + continue; + opl->consumed = true; + OpenPolylineEnd end(opl, false); + for (;;) { + // find a line starting where last one finishes + auto it_next_start = std::lower_bound(by_id.begin(), by_id.end(), end, by_id_lower); + for (; it_next_start != by_id.end() && it_next_start->id() == end.id(); ++ it_next_start) + if (! it_next_start->polyline->consumed) + goto found; + // The current loop could not be closed. Unmark the segment. + opl->consumed = false; + break; + found: + // Attach this polyline to the end of the initial polyline. + if (it_next_start->start) { + auto it = it_next_start->polyline->points.begin(); + std::copy(++ it, it_next_start->polyline->points.end(), back_inserter(opl->points)); + } else { + auto it = it_next_start->polyline->points.rbegin(); + std::copy(++ it, it_next_start->polyline->points.rend(), back_inserter(opl->points)); + } + opl->length += it_next_start->polyline->length; + // Mark the next polyline as consumed. + it_next_start->polyline->points.clear(); + it_next_start->polyline->length = 0.; + it_next_start->polyline->consumed = true; + if (try_connect_reversed) { + // Running in a mode, where the polylines may be connected by mixing their orientations. + // Update the end point lookup structure after the end point of the current polyline was extended. + auto it_end = find_polyline_end(end); + auto it_next_end = find_polyline_end(OpenPolylineEnd(it_next_start->polyline, !it_next_start->start)); + // Swap the end points of the current and next polyline, but keep the polyline ptr and the start flag. + std::swap(opl->end, it_next_end->start ? it_next_end->polyline->start : it_next_end->polyline->end); + // Swap the positions of OpenPolylineEnd structures in the sorted array to match their respective end point positions. + std::swap(*it_end, *it_next_end); + } + // Check whether we closed this loop. + if ((opl->start.edge_id != -1 && opl->start.edge_id == opl->end.edge_id) || + (opl->start.point_id != -1 && opl->start.point_id == opl->end.point_id)) { + // The current loop is complete. Add it to the output. + //assert(opl->points.front().point_id == opl->points.back().point_id); + //assert(opl->points.front().edge_id == opl->points.back().edge_id); + // Remove the duplicate last point. + opl->points.pop_back(); + if (opl->points.size() >= 3) { + if (try_connect_reversed && area(opl->points) < 0) + // The closed polygon is patched from pieces with messed up orientation, therefore + // the orientation of the patched up polygon is not known. + // Orient the patched up polygons CCW. This heuristic may close some holes and cavities. + std::reverse(opl->points.begin(), opl->points.end()); + loops.emplace_back(std::move(opl->points)); + } + opl->points.clear(); + break; + } + // Continue with the current loop. + } + } +} + +// called by TriangleMeshSlicer::make_loops() to connect remaining open polylines across shared triangle edges and vertices, +// possibly closing small gaps. +// Depending on "try_connect_reversed", it may or may not connect segments crossing triangles of opposite orientation. +static void chain_open_polylines_close_gaps(std::vector &open_polylines, Polygons &loops, double max_gap, bool try_connect_reversed) +{ + const coord_t max_gap_scaled = (coord_t)scale_(max_gap); + + // Sort the open polylines by their length, so the new loops will be seeded from longer chains. + // Update the polyline lengths, return only not yet consumed polylines. + std::vector sorted_by_length = open_polylines_sorted(open_polylines, true); + + // Store the end points of open_polylines into ClosestPointInRadiusLookup. + struct OpenPolylineEnd { + OpenPolylineEnd(OpenPolyline *polyline, bool start) : polyline(polyline), start(start) {} + OpenPolyline *polyline; + // Is it the start or end point? + bool start; + const Point& point() const { return start ? polyline->points.front() : polyline->points.back(); } + bool operator==(const OpenPolylineEnd &rhs) const { return this->polyline == rhs.polyline && this->start == rhs.start; } + }; + struct OpenPolylineEndAccessor { + const Point* operator()(const OpenPolylineEnd &pt) const { return pt.polyline->consumed ? nullptr : &pt.point(); } + }; + typedef ClosestPointInRadiusLookup ClosestPointLookupType; + ClosestPointLookupType closest_end_point_lookup(max_gap_scaled); + for (OpenPolyline *opl : sorted_by_length) { + closest_end_point_lookup.insert(OpenPolylineEnd(opl, true)); + if (try_connect_reversed) + closest_end_point_lookup.insert(OpenPolylineEnd(opl, false)); + } + // Try to connect the loops. + for (OpenPolyline *opl : sorted_by_length) { + if (opl->consumed) + continue; + OpenPolylineEnd end(opl, false); + if (try_connect_reversed) + // The end point of this polyline will be modified, thus the following entry will become invalid. Remove it. + closest_end_point_lookup.erase(end); + opl->consumed = true; + size_t n_segments_joined = 1; + for (;;) { + // Find a line starting where last one finishes, only return non-consumed open polylines (OpenPolylineEndAccessor returns null for consumed). + std::pair next_start_and_dist = closest_end_point_lookup.find(end.point()); + const OpenPolylineEnd *next_start = next_start_and_dist.first; + // Check whether we closed this loop. + double current_loop_closing_distance2 = opl->points.front().distance_to_sq(opl->points.back()); + bool loop_closed = current_loop_closing_distance2 < coordf_t(max_gap_scaled) * coordf_t(max_gap_scaled); + if (next_start != nullptr && loop_closed && current_loop_closing_distance2 < next_start_and_dist.second) { + // Heuristics to decide, whether to close the loop, or connect another polyline. + // One should avoid closing loops shorter than max_gap_scaled. + loop_closed = sqrt(current_loop_closing_distance2) < 0.3 * length(opl->points); + } + if (loop_closed) { + // Remove the start point of the current polyline from the lookup. + // Mark the current segment as not consumed, otherwise the closest_end_point_lookup.erase() would fail. + opl->consumed = false; + closest_end_point_lookup.erase(OpenPolylineEnd(opl, true)); + if (current_loop_closing_distance2 == 0.) { + // Remove the duplicate last point. + opl->points.pop_back(); + } else { + // The end points are different, keep both of them. + } + if (opl->points.size() >= 3) { + if (try_connect_reversed && n_segments_joined > 1 && area(opl->points) < 0) + // The closed polygon is patched from pieces with messed up orientation, therefore + // the orientation of the patched up polygon is not known. + // Orient the patched up polygons CCW. This heuristic may close some holes and cavities. + std::reverse(opl->points.begin(), opl->points.end()); + loops.emplace_back(std::move(opl->points)); + } + opl->points.clear(); + opl->consumed = true; + break; + } + if (next_start == nullptr) { + // The current loop could not be closed. Unmark the segment. + opl->consumed = false; + if (try_connect_reversed) + // Re-insert the end point. + closest_end_point_lookup.insert(OpenPolylineEnd(opl, false)); + break; + } + // Attach this polyline to the end of the initial polyline. + if (next_start->start) { + auto it = next_start->polyline->points.begin(); + if (*it == opl->points.back()) + ++ it; + std::copy(it, next_start->polyline->points.end(), back_inserter(opl->points)); + } else { + auto it = next_start->polyline->points.rbegin(); + if (*it == opl->points.back()) + ++ it; + std::copy(it, next_start->polyline->points.rend(), back_inserter(opl->points)); + } + ++ n_segments_joined; + // Remove the end points of the consumed polyline segment from the lookup. + OpenPolyline *opl2 = next_start->polyline; + closest_end_point_lookup.erase(OpenPolylineEnd(opl2, true)); + if (try_connect_reversed) + closest_end_point_lookup.erase(OpenPolylineEnd(opl2, false)); + opl2->points.clear(); + opl2->consumed = true; + // Continue with the current loop. + } + } +} + void TriangleMeshSlicer::make_loops(std::vector &lines, Polygons* loops) const { #if 0 @@ -1260,119 +1599,8 @@ void TriangleMeshSlicer::make_loops(std::vector &lines, Polygo } #endif /* SLIC3R_DEBUG_SLICE_PROCESSING */ - struct OpenPolyline { - OpenPolyline() {}; - OpenPolyline(const IntersectionReference &start, const IntersectionReference &end, Points &&points) : - start(start), end(end), points(std::move(points)), consumed(false) {} - void reverse() { - std::swap(start, end); - std::reverse(points.begin(), points.end()); - } - IntersectionReference start; - IntersectionReference end; - Points points; - bool consumed; - }; std::vector open_polylines; - { - // Build a map of lines by edge_a_id and a_id. - std::vector by_edge_a_id; - std::vector by_a_id; - by_edge_a_id.reserve(lines.size()); - by_a_id.reserve(lines.size()); - for (IntersectionLine &line : lines) { - if (! line.skip()) { - if (line.edge_a_id != -1) - by_edge_a_id.emplace_back(&line); - if (line.a_id != -1) - by_a_id.emplace_back(&line); - } - } - auto by_edge_lower = [](const IntersectionLine* il1, const IntersectionLine *il2) { return il1->edge_a_id < il2->edge_a_id; }; - auto by_vertex_lower = [](const IntersectionLine* il1, const IntersectionLine *il2) { return il1->a_id < il2->a_id; }; - std::sort(by_edge_a_id.begin(), by_edge_a_id.end(), by_edge_lower); - std::sort(by_a_id.begin(), by_a_id.end(), by_vertex_lower); - // Chain the segments with a greedy algorithm, collect the loops and unclosed polylines. - IntersectionLines::iterator it_line_seed = lines.begin(); - for (;;) { - // take first spare line and start a new loop - IntersectionLine *first_line = nullptr; - for (; it_line_seed != lines.end(); ++ it_line_seed) - if (it_line_seed->is_seed_candidate()) { - //if (! it_line_seed->skip()) { - first_line = &(*it_line_seed ++); - break; - } - if (first_line == nullptr) - break; - first_line->set_skip(); - Points loop_pts; - loop_pts.emplace_back(first_line->a); - IntersectionLine *last_line = first_line; - - /* - printf("first_line edge_a_id = %d, edge_b_id = %d, a_id = %d, b_id = %d, a = %d,%d, b = %d,%d\n", - first_line->edge_a_id, first_line->edge_b_id, first_line->a_id, first_line->b_id, - first_line->a.x, first_line->a.y, first_line->b.x, first_line->b.y); - */ - - IntersectionLine key; - for (;;) { - // find a line starting where last one finishes - IntersectionLine* next_line = nullptr; - if (last_line->edge_b_id != -1) { - key.edge_a_id = last_line->edge_b_id; - auto it_begin = std::lower_bound(by_edge_a_id.begin(), by_edge_a_id.end(), &key, by_edge_lower); - if (it_begin != by_edge_a_id.end()) { - auto it_end = std::upper_bound(it_begin, by_edge_a_id.end(), &key, by_edge_lower); - for (auto it_line = it_begin; it_line != it_end; ++ it_line) - if (! (*it_line)->skip()) { - next_line = *it_line; - break; - } - } - } - if (next_line == nullptr && last_line->b_id != -1) { - key.a_id = last_line->b_id; - auto it_begin = std::lower_bound(by_a_id.begin(), by_a_id.end(), &key, by_vertex_lower); - if (it_begin != by_a_id.end()) { - auto it_end = std::upper_bound(it_begin, by_a_id.end(), &key, by_vertex_lower); - for (auto it_line = it_begin; it_line != it_end; ++ it_line) - if (! (*it_line)->skip()) { - next_line = *it_line; - break; - } - } - } - if (next_line == nullptr) { - // Check whether we closed this loop. - if ((first_line->edge_a_id != -1 && first_line->edge_a_id == last_line->edge_b_id) || - (first_line->a_id != -1 && first_line->a_id == last_line->b_id)) { - // The current loop is complete. Add it to the output. - loops->emplace_back(std::move(loop_pts)); - #ifdef SLIC3R_TRIANGLEMESH_DEBUG - printf(" Discovered %s polygon of %d points\n", (p.is_counter_clockwise() ? "ccw" : "cw"), (int)p.points.size()); - #endif - } else { - // This is an open polyline. Add it to the list of open polylines. These open polylines will processed later. - loop_pts.emplace_back(last_line->b); - open_polylines.emplace_back(OpenPolyline( - IntersectionReference(first_line->a_id, first_line->edge_a_id), - IntersectionReference(last_line->b_id, last_line->edge_b_id), std::move(loop_pts))); - } - break; - } - /* - printf("next_line edge_a_id = %d, edge_b_id = %d, a_id = %d, b_id = %d, a = %d,%d, b = %d,%d\n", - next_line->edge_a_id, next_line->edge_b_id, next_line->a_id, next_line->b_id, - next_line->a.x, next_line->a.y, next_line->b.x, next_line->b.y); - */ - loop_pts.emplace_back(next_line->a); - last_line = next_line; - next_line->set_skip(); - } - } - } + chain_lines_by_triangle_connectivity(lines, *loops, open_polylines); #ifdef SLIC3R_DEBUG_SLICE_PROCESSING { @@ -1388,98 +1616,8 @@ void TriangleMeshSlicer::make_loops(std::vector &lines, Polygo // Now process the open polylines. // Do it in two rounds, first try to connect in the same direction only, // then try to connect the open polylines in reversed order as well. - for (size_t round = 0; round < 2 && ! open_polylines.empty(); ++ round) { - bool try_connect_reversed = round == 1; - // Store the end points of open_polylines into vectors sorted - struct OpenPolylineEnd { - OpenPolylineEnd(OpenPolyline *polyline, bool start) : polyline(polyline), start(start) {} - OpenPolyline *polyline; - // Is it the start or end point? - bool start; - const IntersectionReference& ipref() const { return start ? polyline->start : polyline->end; } - // Return a unique ID for the intersection point. - // Return a positive id for a point, or a negative id for an edge. - int id() const { const IntersectionReference &r = ipref(); return (r.point_id >= 0) ? r.point_id : - r.edge_id; } - bool operator==(const OpenPolylineEnd &rhs) const { return this->polyline == rhs.polyline && this->start == rhs.start; } - }; - auto by_id_lower = [](const OpenPolylineEnd &ope1, const OpenPolylineEnd &ope2) { return ope1.id() < ope2.id(); }; - std::vector by_id; - by_id.reserve(2 * open_polylines.size()); - for (OpenPolyline &opl : open_polylines) { - if (opl.start.point_id != -1 || opl.start.edge_id != -1) - by_id.emplace_back(OpenPolylineEnd(&opl, true)); - if (try_connect_reversed && (opl.end.point_id != -1 || opl.end.edge_id != -1)) - by_id.emplace_back(OpenPolylineEnd(&opl, false)); - } - std::sort(by_id.begin(), by_id.end(), by_id_lower); - // Find an iterator to by_id_lower for the particular end of OpenPolyline (by comparing the OpenPolyline pointer and the start attribute). - auto find_polyline_end = [&by_id, by_id_lower](const OpenPolylineEnd &end) -> std::vector::iterator { - for (auto it = std::lower_bound(by_id.begin(), by_id.end(), end, by_id_lower); - it != by_id.end() && it->id() == end.id(); ++ it) - if (*it == end) - return it; - return by_id.end(); - }; - // Try to connect the loops. - for (OpenPolyline &opl : open_polylines) { - if (opl.consumed) - continue; - opl.consumed = true; - OpenPolylineEnd end(&opl, false); - for (;;) { - // find a line starting where last one finishes - auto it_next_start = std::lower_bound(by_id.begin(), by_id.end(), end, by_id_lower); - for (; it_next_start != by_id.end() && it_next_start->id() == end.id(); ++ it_next_start) - if (! it_next_start->polyline->consumed) - goto found; - // The current loop could not be closed. Unmark the segment. - opl.consumed = false; - break; - found: - // Attach this polyline to the end of the initial polyline. - if (it_next_start->start) { - auto it = it_next_start->polyline->points.begin(); - std::copy(++ it, it_next_start->polyline->points.end(), back_inserter(opl.points)); - } else { - auto it = it_next_start->polyline->points.rbegin(); - std::copy(++ it, it_next_start->polyline->points.rend(), back_inserter(opl.points)); - } - // Mark the next polyline as consumed. - it_next_start->polyline->points.clear(); - it_next_start->polyline->consumed = true; - if (try_connect_reversed) { - // Running in a mode, where the polylines may be connected by mixing their orientations. - // Update the end point lookup structure after the end point of the current polyline was extended. - auto it_end = find_polyline_end(end); - auto it_next_end = find_polyline_end(OpenPolylineEnd(it_next_start->polyline, !it_next_start->start)); - // Swap the end points of the current and next polyline, but keep the polyline ptr and the start flag. - std::swap(opl.end, it_next_end->start ? it_next_end->polyline->start : it_next_end->polyline->end); - // Swap the positions of OpenPolylineEnd structures in the sorted array to match their respective end point positions. - std::swap(*it_end, *it_next_end); - } - // Check whether we closed this loop. - if ((opl.start.edge_id != -1 && opl.start.edge_id == opl.end.edge_id) || - (opl.start.point_id != -1 && opl.start.point_id == opl.end.point_id)) { - // The current loop is complete. Add it to the output. - //assert(opl.points.front().point_id == opl.points.back().point_id); - //assert(opl.points.front().edge_id == opl.points.back().edge_id); - // Remove the duplicate last point. - opl.points.pop_back(); - if (opl.points.size() >= 3) { - if (try_connect_reversed && area(opl.points) < 0) - // The closed polygon is patched from pieces with messed up orientation, therefore - // the orientation of the patched up polygon is not known. - // Orient the patched up polygons CCW. This heuristic may close some holes and cavities. - std::reverse(opl.points.begin(), opl.points.end()); - loops->emplace_back(std::move(opl.points)); - } - opl.points.clear(); - break; - } - // Continue with the current loop. - } - } - } + chain_open_polylines_exact(open_polylines, *loops, false); + chain_open_polylines_exact(open_polylines, *loops, true); #ifdef SLIC3R_DEBUG_SLICE_PROCESSING { @@ -1500,105 +1638,9 @@ void TriangleMeshSlicer::make_loops(std::vector &lines, Polygo // Try to close gaps. // Do it in two rounds, first try to connect in the same direction only, // then try to connect the open polylines in reversed order as well. - const coord_t max_gap_scaled = (coord_t)scale_(2.); // 2mm - for (size_t round = 0; round < 2 && ! open_polylines.empty(); ++ round) { - bool try_connect_reversed = round == 1; - // Store the end points of open_polylines into ClosestPointInRadiusLookup. - struct OpenPolylineEnd { - OpenPolylineEnd(OpenPolyline *polyline, bool start) : polyline(polyline), start(start) {} - OpenPolyline *polyline; - // Is it the start or end point? - bool start; - const Point& point() const { return start ? polyline->points.front() : polyline->points.back(); } - bool operator==(const OpenPolylineEnd &rhs) const { return this->polyline == rhs.polyline && this->start == rhs.start; } - }; - struct OpenPolylineEndAccessor { - const Point* operator()(const OpenPolylineEnd &pt) const { return pt.polyline->consumed ? nullptr : &pt.point(); } - }; - typedef ClosestPointInRadiusLookup ClosestPointLookupType; - ClosestPointLookupType closest_end_point_lookup(max_gap_scaled); - for (OpenPolyline &opl : open_polylines) { - closest_end_point_lookup.insert(OpenPolylineEnd(&opl, true)); - if (try_connect_reversed) - closest_end_point_lookup.insert(OpenPolylineEnd(&opl, false)); - } - // Try to connect the loops. - for (OpenPolyline &opl : open_polylines) { - if (opl.consumed) - continue; - OpenPolylineEnd end(&opl, false); - if (try_connect_reversed) - // The end point of this polyline will be modified, thus the following entry will become invalid. Remove it. - closest_end_point_lookup.erase(end); - opl.consumed = true; - size_t n_segments_joined = 1; - for (;;) { - // Find a line starting where last one finishes, only return non-consumed open polylines (OpenPolylineEndAccessor returns null for consumed). - std::pair next_start_and_dist = closest_end_point_lookup.find(end.point()); - const OpenPolylineEnd *next_start = next_start_and_dist.first; - // Check whether we closed this loop. - double current_loop_closing_distance2 = opl.points.front().distance_to_sq(opl.points.back()); - bool loop_closed = current_loop_closing_distance2 < coordf_t(max_gap_scaled) * coordf_t(max_gap_scaled); - if (next_start != nullptr && loop_closed && current_loop_closing_distance2 < next_start_and_dist.second) { - // Heuristics to decide, whether to close the loop, or connect another polyline. - // One should avoid closing loops shorter than max_gap_scaled. - loop_closed = sqrt(current_loop_closing_distance2) < 0.3 * length(opl.points); - } - if (loop_closed) { - // Remove the start point of the current polyline from the lookup. - // Mark the current segment as not consumed, otherwise the closest_end_point_lookup.erase() would fail. - opl.consumed = false; - closest_end_point_lookup.erase(OpenPolylineEnd(&opl, true)); - if (current_loop_closing_distance2 == 0.) { - // Remove the duplicate last point. - opl.points.pop_back(); - } else { - // The end points are different, keep both of them. - } - if (opl.points.size() >= 3) { - if (try_connect_reversed && n_segments_joined > 1 && area(opl.points) < 0) - // The closed polygon is patched from pieces with messed up orientation, therefore - // the orientation of the patched up polygon is not known. - // Orient the patched up polygons CCW. This heuristic may close some holes and cavities. - std::reverse(opl.points.begin(), opl.points.end()); - loops->emplace_back(std::move(opl.points)); - } - opl.points.clear(); - opl.consumed = true; - break; - } - if (next_start == nullptr) { - // The current loop could not be closed. Unmark the segment. - opl.consumed = false; - if (try_connect_reversed) - // Re-insert the end point. - closest_end_point_lookup.insert(OpenPolylineEnd(&opl, false)); - break; - } - // Attach this polyline to the end of the initial polyline. - if (next_start->start) { - auto it = next_start->polyline->points.begin(); - if (*it == opl.points.back()) - ++ it; - std::copy(it, next_start->polyline->points.end(), back_inserter(opl.points)); - } else { - auto it = next_start->polyline->points.rbegin(); - if (*it == opl.points.back()) - ++ it; - std::copy(it, next_start->polyline->points.rend(), back_inserter(opl.points)); - } - ++ n_segments_joined; - // Remove the end points of the consumed polyline segment from the lookup. - OpenPolyline *opl2 = next_start->polyline; - closest_end_point_lookup.erase(OpenPolylineEnd(opl2, true)); - if (try_connect_reversed) - closest_end_point_lookup.erase(OpenPolylineEnd(opl2, false)); - opl2->points.clear(); - opl2->consumed = true; - // Continue with the current loop. - } - } - } + const double max_gap = 2.; //mm + chain_open_polylines_close_gaps(open_polylines, *loops, max_gap, false); + chain_open_polylines_close_gaps(open_polylines, *loops, max_gap, true); #ifdef SLIC3R_DEBUG_SLICE_PROCESSING {