Autogenerate supportPoints by surface angle

src/libslic3r/CMakeLists.txt

@@ -444,8 +444,6 @@ set(SLIC3R_SOURCES
     SLA/SupportPoint.hpp
     SLA/SupportPointGenerator.hpp
     SLA/SupportPointGenerator.cpp
-    SLA/SupportPointGeneratorNew.hpp
-    SLA/SupportPointGeneratorNew.cpp
     SLA/Clustering.hpp
     SLA/Clustering.cpp
     SLA/ReprojectPointsOnMesh.hpp

src/libslic3r/Format/3mf.cpp

@@ -1420,20 +1420,21 @@ namespace Slic3r {
 
                 if (version == 0) {
                     for (unsigned int i=0; i<object_data_points.size(); i+=3)
-                    sla_support_points.emplace_back(float(std::atof(object_data_points[i+0].c_str())),
+                    sla_support_points.push_back(sla::SupportPoint{Vec3f(
+                                                    float(std::atof(object_data_points[i+0].c_str())),
                                                     float(std::atof(object_data_points[i+1].c_str())),
-													float(std::atof(object_data_points[i+2].c_str())),
+													float(std::atof(object_data_points[i+2].c_str()))),
-                                                    0.4f,
+                                                    0.4f});
-                                                    false);
                 }
                 if (version == 1) {
                     for (unsigned int i=0; i<object_data_points.size(); i+=5)
-                    sla_support_points.emplace_back(float(std::atof(object_data_points[i+0].c_str())),
+                    sla_support_points.push_back(sla::SupportPoint{Vec3f(
+                                                    float(std::atof(object_data_points[i+0].c_str())),
                                                     float(std::atof(object_data_points[i+1].c_str())),
-                                                    float(std::atof(object_data_points[i+2].c_str())),
+                                                    float(std::atof(object_data_points[i+2].c_str()))),
-                                                    float(std::atof(object_data_points[i+3].c_str())),
+                                                    float(std::atof(object_data_points[i+3].c_str()))});
 													//FIXME storing boolean as 0 / 1 and importing it as float.
-                                                    std::abs(std::atof(object_data_points[i+4].c_str()) - 1.) < EPSILON);
+                                                    //std::abs(std::atof(object_data_points[i+4].c_str()) - 1.) < EPSILON);
                 }
 
                 if (!sla_support_points.empty())
@@ -3542,7 +3543,7 @@ namespace Slic3r {
 
                 // Store the layer height profile as a single space separated list.
                 for (size_t i = 0; i < sla_support_points.size(); ++i) {
-                    sprintf(buffer, (i==0 ? "%f %f %f %f %f" : " %f %f %f %f %f"),  sla_support_points[i].pos(0), sla_support_points[i].pos(1), sla_support_points[i].pos(2), sla_support_points[i].head_front_radius, (float)sla_support_points[i].is_new_island);
+                    sprintf(buffer, (i==0 ? "%f %f %f %f %f" : " %f %f %f %f %f"),  sla_support_points[i].pos(0), sla_support_points[i].pos(1), sla_support_points[i].pos(2), sla_support_points[i].head_front_radius, (float)(sla_support_points[i].is_island()));
                     out += buffer;
                 }
                 out += "\n";

src/libslic3r/Format/AMF.cpp

@@ -774,7 +774,7 @@ void AMFParserContext::endElement(const char * /* name */)
 
                     point(coord_idx) = float(atof(p));
                     if (++coord_idx == 5) {
-                        m_object->sla_support_points.push_back(sla::SupportPoint(point));
+                        m_object->sla_support_points.push_back(sla::SupportPoint{Vec3f(point[0], point[1], point[2]), point[3]});
                         coord_idx = 0;
                     }
 					if (end == nullptr)

src/libslic3r/SLA/SupportPoint.hpp

@@ -7,11 +7,7 @@
 
 #include <libslic3r/Point.hpp>
 
-namespace Slic3r {
+namespace Slic3r::sla {
-
-class ModelObject;
-
-namespace sla {
 
 // An enum to keep track of where the current points on the ModelObject came from.
 enum class PointsStatus {
@@ -21,58 +17,47 @@ enum class PointsStatus {
     UserModified    // User has done some edits.
 };
 
+// Reason of automatic support placement usage
+enum class SupportPointType {
+    manual_add,
+    island, // no move, island should be grouped
+    slope,
+    thin,
+    stability,
+    edge
+};
+
+/// <summary>
+/// Stereolithography(SLA) support point
+/// </summary>
 struct SupportPoint
 {
-    Vec3f pos;
+    // Position on model surface
-    float head_front_radius;
+    Vec3f pos = Vec3f::Zero(); // [in mm]
-    bool  is_new_island;
 
-    SupportPoint()
+    // radius of the touching interface
-        : pos(Vec3f::Zero()), head_front_radius(0.f), is_new_island(false)
+    // Also define force it must keep
-    {}
+    float head_front_radius = 0.f; // [in mm]
 
-    SupportPoint(float pos_x,
+    // type
-                 float pos_y,
+    SupportPointType type{SupportPointType::manual_add};
-                 float pos_z,
-                 float head_radius,
-                 bool  new_island = false)
-        : pos(pos_x, pos_y, pos_z)
-        , head_front_radius(head_radius)
-        , is_new_island(new_island)
-    {}
     
-    SupportPoint(Vec3f position, float head_radius, bool new_island = false)
+    bool is_island() const { return type == SupportPointType::island; }
-        : pos(position)
+    template<class Archive> void serialize(Archive &ar){
-        , head_front_radius(head_radius)
+        ar(pos, head_front_radius, type);
-        , is_new_island(new_island)
+    }
-    {}
 
-    SupportPoint(Eigen::Matrix<float, 5, 1, Eigen::DontAlign> data)
+    // unsaved changes + cache invalidation
-        : pos(data(0), data(1), data(2))
+    bool operator==(const SupportPoint &sp) const {
-        , head_front_radius(data(3))
-        , is_new_island(data(4) != 0.f)
-    {}
-    
-    bool operator==(const SupportPoint &sp) const
-    {
         float rdiff = std::abs(head_front_radius - sp.head_front_radius);
-        return (pos == sp.pos) && rdiff < float(EPSILON) &&
+        return (pos == sp.pos) && rdiff < float(EPSILON) && type == sp.type;
-               is_new_island == sp.is_new_island;
     }
 
     bool operator!=(const SupportPoint &sp) const { return !(sp == (*this)); }
 
-    template<class Archive> void serialize(Archive &ar)
-    {
-        ar(pos, head_front_radius, is_new_island);
-    }
 };
-
 using SupportPoints = std::vector<SupportPoint>;
 
-SupportPoints transformed_support_points(const ModelObject &mo,
+} // namespace Slic3r::sla
-                                         const Transform3d &trafo);
-
-}} // namespace Slic3r::sla
 
 #endif // SUPPORTPOINT_HPP

src/libslic3r/SLA/SupportPointGenerator.hpp

@@ -1,262 +1,191 @@
-///|/ Copyright (c) Prusa Research 2020 - 2022 Vojtěch Bubník @bubnikv, Tomáš Mészáros @tamasmeszaros, Lukáš Matěna @lukasmatena
+///|/ Copyright (c) Prusa Research 2024 Filip Sykala @Jony01
 ///|/
 ///|/ PrusaSlicer is released under the terms of the AGPLv3 or higher
 ///|/
 #ifndef SLA_SUPPORTPOINTGENERATOR_HPP
 #define SLA_SUPPORTPOINTGENERATOR_HPP
 
-#include <libslic3r/AABBMesh.hpp>
-#include <libslic3r/SLA/SupportPoint.hpp>
-#include <libslic3r/BoundingBox.hpp>
-#include <libslic3r/ClipperUtils.hpp>
-#include <libslic3r/Point.hpp>
-#include <boost/container/small_vector.hpp>
-#include <stdint.h>
-#include <random>
-#include <cmath>
-#include <cstddef>
-#include <functional>
-#include <unordered_map>
-#include <utility>
 #include <vector>
-#include <cinttypes>
+#include <functional>
 
+#include <boost/container/small_vector.hpp>
+
+#include "libslic3r/Point.hpp"
 #include "libslic3r/ExPolygon.hpp"
-#include "libslic3r/Polygon.hpp"
+#include "libslic3r/SLA/SupportPoint.hpp"
-#include "libslic3r/libslic3r.h"
 
-namespace Slic3r {
+namespace Slic3r::sla {
-class AABBMesh;
-}  // namespace Slic3r
 
-// #define SLA_SUPPORTPOINTGEN_DEBUG
+/// <summary>
+/// Configuration for automatic support placement
+/// </summary>
+struct SupportPointGeneratorConfig{
+    /// <summary>
+    /// 0 mean only one support point for each island
+    /// lower than one mean less amount of support points
+    /// 1 mean fine tuned sampling
+    /// more than one mean bigger amout of support points
+    /// </summary>
+    float density_relative{1.f};
 
-namespace Slic3r { namespace sla {
+    /// <summary>
+    /// Size range for support point interface (head)
+    /// </summary>
+    MinMax<float> head_diameter = {0.2f, 0.6f}; // [in mm]
 
-class SupportPointGenerator {
+    // FIXME: calculate actual pixel area from printer config:
-public:
+    // const float pixel_area =
-    struct Config final {
+    // pow(wxGetApp().preset_bundle->project_config.option<ConfigOptionFloat>("display_width") /
-        float density_relative {1.f};
+    // wxGetApp().preset_bundle->project_config.option<ConfigOptionInt>("display_pixels_x"), 2.f); //
-        float minimal_distance {1.f};
+    // Minimal island Area to print - TODO: Should be modifiable from UI
-        float head_diameter {0.4f};
+    // !! Filter should be out of sampling algorithm !!
-
+    float minimal_island_area = pow(0.047f, 2.f); // [in mm^2] pixel_area
-        // Originally calibrated to 7.7f, reduced density by Tamas to 70% which is 11.1 (7.7 / 0.7) to adjust for new algorithm changes in tm_suppt_gen_improve
-        inline float support_force() const { return 11.1f / density_relative; } // a force one point can support       (arbitrary force unit)
-
-        // FIXME: calculate actual pixel area from printer config:
-        //const float pixel_area = pow(wxGetApp().preset_bundle->project_config.option<ConfigOptionFloat>("display_width") / wxGetApp().preset_bundle->project_config.option<ConfigOptionInt>("display_pixels_x"), 2.f); //
-        // Minimal island Area to print - TODO: Should be modifiable from UI
-        const float minimal_island_area = pow(0.047f, 2.f); // [in mm^2] pixel_area
-    };
-    
-    SupportPointGenerator(const AABBMesh& emesh, const std::vector<ExPolygons>& slices,
-                    const std::vector<float>& heights, const Config& config, std::function<void(void)> throw_on_cancel, std::function<void(int)> statusfn);
-    
-    SupportPointGenerator(const AABBMesh& emesh, const Config& config, std::function<void(void)> throw_on_cancel, std::function<void(int)> statusfn);
-    
-    const std::vector<SupportPoint>& output() const { return m_output; }
-    std::vector<SupportPoint>& output() { return m_output; }
-    
-    struct MyLayer;
-    
-    // Keep data for one area(ExPlygon) on the layer(on slice Expolygons)
-    struct Structure {
-        Structure(MyLayer &layer, const ExPolygon& poly, const BoundingBox &bbox, float area) :
-            layer(&layer), polygon(&poly), bbox(bbox), area(area)
-#ifdef SLA_SUPPORTPOINTGEN_DEBUG
-            , unique_id(std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now().time_since_epoch()))
-#endif /* SLA_SUPPORTPOINTGEN_DEBUG */
-        {}
-        // Parent layer - with all ExPolygons in layer + layer_height
-        MyLayer *layer;
-        // Source ExPolygon
-        const ExPolygon* polygon = nullptr;
-        // Cache bounding box of polygon
-        const BoundingBox bbox;
-        // area of polygon [in mm^2] without holes
-        const float area = 0.f;
-
-        // How well is this ExPolygon held to the print base?
-        // Positive number, the higher the better.
-        float supports_force_this_layer     = 0.f;
-        float supports_force_inherited      = 0.f;
-        float supports_force_total() const { return this->supports_force_this_layer + this->supports_force_inherited; }
-#ifdef SLA_SUPPORTPOINTGEN_DEBUG
-        std::chrono::milliseconds unique_id;
-#endif /* SLA_SUPPORTPOINTGEN_DEBUG */
-        
-        struct Link {
-            Link(Structure *island, float overlap_area) : island(island), overlap_area(overlap_area) {}
-            Structure   *island;
-            float        overlap_area;
-        };
-
-#ifdef NDEBUG
-        // In release mode, use the optimized container.
-        boost::container::small_vector<Link, 4> islands_above;
-        boost::container::small_vector<Link, 4> islands_below;
-#else
-        // In debug mode, use the standard vector, which is well handled by debugger visualizer.
-        std::vector<Link>					 	islands_above;
-        std::vector<Link>						islands_below;
-#endif
-        // Overhangs, that are dangling considerably.
-        ExPolygons                              dangling_areas;
-        // Complete overhangs.
-        ExPolygons                              overhangs;
-        // Overhangs, where the surface must slope.
-        ExPolygons                              overhangs_slopes;
-        // Sum of all overhang areas from structure
-        float                                   overhangs_area = 0.f; // [in mm^2]
-        
-        bool overlaps(const Structure &rhs) const { 
-            return this->bbox.overlap(rhs.bbox) && this->polygon->overlaps(*rhs.polygon);
-        }
-        float overlap_area(const Structure &rhs) const { 
-            double out = 0.;
-            if (this->bbox.overlap(rhs.bbox)) {
-                Polygons polys = intersection(*this->polygon, *rhs.polygon);
-                for (const Polygon &poly : polys)
-                    out += poly.area();
-            }
-            return float(out);
-        }
-        float area_below() const { 
-            float area = 0.f; 
-            for (const Link &below : this->islands_below) 
-                area += below.island->area; 
-            return area;
-        }
-        Polygons polygons_below() const { 
-            size_t cnt = 0;
-            for (const Link &below : this->islands_below)
-                cnt += 1 + below.island->polygon->holes.size();
-            Polygons out;
-            out.reserve(cnt);
-            for (const Link &below : this->islands_below) {
-                out.emplace_back(below.island->polygon->contour);
-                append(out, below.island->polygon->holes);
-            }
-            return out;
-        }
-        ExPolygons expolygons_below() const { 
-            ExPolygons out;
-            out.reserve(this->islands_below.size());
-            for (const Link &below : this->islands_below)
-                out.emplace_back(*below.island->polygon);
-            return out;
-        }
-        // Positive deficit of the supports. If negative, this area is well supported. If positive, more supports need to be added.
-        float support_force_deficit(const float tear_pressure) const { return this->area * tear_pressure - this->supports_force_total(); }
-    };
-    
-    struct MyLayer {
-        MyLayer(const size_t layer_id, coordf_t print_z) : layer_id(layer_id), print_z(print_z) {}
-        // index into heights + slices
-        size_t                  layer_id;
-        // Absolute distance from Zero - copy value from heights<float>
-        coordf_t print_z; // [in mm]
-        std::vector<Structure>  islands;
-    };
-    
-    struct RichSupportPoint {
-        Vec3f        position;
-        Structure   *island;
-    };
-    
-    struct PointGrid3D {
-        struct GridHash {
-            std::size_t operator()(const Vec3i &cell_id) const {
-                return std::hash<int>()(cell_id.x()) ^ std::hash<int>()(cell_id.y() * 593) ^ std::hash<int>()(cell_id.z() * 7919);
-            }
-        };
-        typedef std::unordered_multimap<Vec3i, RichSupportPoint, GridHash> Grid;
-        
-        Vec3f   cell_size;
-        Grid    grid;
-        
-        Vec3i cell_id(const Vec3f &pos) {
-            return Vec3i(int(floor(pos.x() / cell_size.x())),
-                         int(floor(pos.y() / cell_size.y())),
-                         int(floor(pos.z() / cell_size.z())));
-        }
-        
-        void insert(const Vec2f &pos, Structure *island) {
-            RichSupportPoint pt;
-            pt.position = Vec3f(pos.x(), pos.y(), float(island->layer->print_z));
-            pt.island   = island;
-            grid.emplace(cell_id(pt.position), pt);
-        }
-        
-        bool collides_with(const Vec2f &pos, float print_z, float radius) {
-            Vec3f pos3d(pos.x(), pos.y(), print_z);
-            Vec3i cell = cell_id(pos3d);
-            std::pair<Grid::const_iterator, Grid::const_iterator> it_pair = grid.equal_range(cell);
-            if (collides_with(pos3d, radius, it_pair.first, it_pair.second))
-                return true;
-            for (int i = -1; i < 2; ++ i)
-                for (int j = -1; j < 2; ++ j)
-                    for (int k = -1; k < 1; ++ k) {
-                        if (i == 0 && j == 0 && k == 0)
-                            continue;
-                        it_pair = grid.equal_range(cell + Vec3i(i, j, k));
-                        if (collides_with(pos3d, radius, it_pair.first, it_pair.second))
-                            return true;
-                    }
-            return false;
-        }
-        
-    private:
-        bool collides_with(const Vec3f &pos, float radius, Grid::const_iterator it_begin, Grid::const_iterator it_end) {
-            for (Grid::const_iterator it = it_begin; it != it_end; ++ it) {
-                float dist2 = (it->second.position - pos).squaredNorm();
-                if (dist2 < radius * radius)
-                    return true;
-            }
-            return false;
-        }
-    };
-    
-    void execute(const std::vector<ExPolygons> &slices,
-                 const std::vector<float> &     heights);
-    
-    void seed(std::mt19937::result_type s) { m_rng.seed(s); }
-private:
-    std::vector<SupportPoint> m_output;
-    
-    // Configuration
-    SupportPointGenerator::Config m_config;
-    
-    void process(const std::vector<ExPolygons>& slices, const std::vector<float>& heights);
-
-public:
-    enum IslandCoverageFlags : uint8_t { icfNone = 0x0, icfIsNew = 0x1, icfWithBoundary = 0x2 };
-
-private:
-
-    void uniformly_cover(const ExPolygons& islands, Structure& structure, float deficit, PointGrid3D &grid3d, IslandCoverageFlags flags = icfNone);
-
-    void add_support_points(Structure& structure, PointGrid3D &grid3d);
-
-    void project_onto_mesh(std::vector<SupportPoint>& points) const;
-
-#ifdef SLA_SUPPORTPOINTGEN_DEBUG
-    static void output_expolygons(const ExPolygons& expolys, const std::string &filename);
-    static void output_structures(const std::vector<Structure> &structures);
-#endif // SLA_SUPPORTPOINTGEN_DEBUG
-    
-    const AABBMesh& m_emesh;
-    std::function<void(void)> m_throw_on_cancel;
-    std::function<void(int)>  m_statusfn;
-    
-    std::mt19937 m_rng;
 };
 
-void remove_bottom_points(std::vector<SupportPoint> &pts, float lvl);
+struct LayerPart; // forward decl.
+using LayerParts = std::vector<LayerPart>;
 
-std::vector<Vec2f> sample_expolygon(const ExPolygon &expoly, float samples_per_mm2, std::mt19937 &rng);
+struct PartLink
-void sample_expolygon_boundary(const ExPolygon &expoly, float samples_per_mm, std::vector<Vec2f> &out, std::mt19937 &rng);
+{
+    LayerParts::const_iterator part_it;
+    // float overlap_area; // sum of overlap areas
+    // ExPolygons overlap; // clipper intersection_ex
+    // ExPolygons overhang; // clipper diff_ex
+};
+#ifdef NDEBUG
+// In release mode, use the optimized container.
+using PartLinks = boost::container::small_vector<PartLink, 4>;
+#else
+// In debug mode, use the standard vector, which is well handled by debugger visualizer.
+using PartLinks = std::vector<PartLink>;
+#endif
 
-}} // namespace Slic3r::sla
+// Part on layer is defined by its shape 
+struct LayerPart {
+    // Pointer to expolygon stored in input
+    const ExPolygon *shape;
 
-#endif // SUPPORTPOINTGENERATOR_HPP
+    // rectangular bounding box of shape
+    BoundingBox shape_extent;
+
+    // uniformly sampled shape contour
+    Slic3r::Points samples;
+    // IMPROVE: sample only overhangs part of shape
+
+    // Parts from previous printed layer, which is connected to current part
+    PartLinks prev_parts;
+    PartLinks next_parts;
+};
+
+/// <summary>
+/// Extend support point with information from layer
+/// </summary>
+struct LayerSupportPoint: public SupportPoint
+{
+    // Pointer on source ExPolygon otherwise nullptr
+    //const LayerPart *part{nullptr}; 
+
+    // 2d coordinate on layer
+    // use only when part is not nullptr
+    Point position_on_layer; // [scaled_ unit]
+
+    // 2d direction into expolygon mass
+    // used as ray to positioning 3d point on mesh surface
+    // Island has direction [0,0] - should be placed on surface from bottom
+    Point direction_to_mass;
+};
+using LayerSupportPoints = std::vector<LayerSupportPoint>;
+
+/// <summary>
+/// One slice divided into 
+/// </summary>
+struct Layer
+{
+    // index into parent Layesr + heights + slices 
+    // [[deprecated]] Use index to layers insted of adress from item
+    size_t layer_id;
+
+    // Absolute distance from Zero - copy value from heights<float>
+    // [[deprecated]] Use index to layers insted of adress from item
+    double print_z; // [in mm]
+
+    // data for one expolygon
+    LayerParts parts;
+};
+using Layers = std::vector<Layer>;
+
+/// <summary>
+/// Keep state of Support Point generation
+/// Used for resampling with different configuration
+/// </summary>
+struct SupportPointGeneratorData
+{
+    // Input slices of mesh
+    std::vector<ExPolygons> slices;
+    // Same size as slices
+    std::vector<float> heights;
+
+    // link to slices
+    Layers layers;
+};
+
+// call during generation of support points to check cancel event
+using ThrowOnCancel = std::function<void(void)>;
+// call to say progress of generation into gui in range from 0 to 100
+using StatusFunction= std::function<void(int)>;
+
+/// <summary>
+/// Prepare data for generate support points
+/// Used for interactive resampling to store permanent data between configuration changes.,
+/// Everything which could be prepared are stored into result.
+/// Need to regenerate on mesh change(Should be connected with ObjectId) OR change of slicing heights
+/// </summary>
+/// <param name="slices">Countour cut from mesh</param>
+/// <param name="heights">Heights of the slices - Same size as slices</param>
+/// <param name="throw_on_cancel">Call in meanwhile to check cancel event</param>
+/// <param name="statusfn">Say progress of generation into gui</param>
+/// <returns>Data prepared for generate support points</returns>
+SupportPointGeneratorData prepare_generator_data(
+    std::vector<ExPolygons> &&slices,
+    std::vector<float> &&heights,
+    ThrowOnCancel throw_on_cancel,
+    StatusFunction statusfn
+);
+
+/// <summary>
+/// Generate support points on islands by configuration parameters
+/// </summary>
+/// <param name="data">Preprocessed data needed for sampling</param>
+/// <param name="config">Define density of samples</param>
+/// <param name="throw_on_cancel">Call in meanwhile to check cancel event</param>
+/// <param name="statusfn">Progress of generation into gui</param>
+/// <returns>Generated support points</returns>
+LayerSupportPoints generate_support_points(
+    const SupportPointGeneratorData &data,
+    const SupportPointGeneratorConfig &config,
+    ThrowOnCancel throw_on_cancel,
+    StatusFunction statusfn
+);
+} // namespace Slic3r::sla
+
+// TODO: Not sure if it is neccessary & Should be in another file
+namespace Slic3r{
+class AABBMesh;
+namespace sla {
+/// <summary>
+/// Move support points on surface of mesh
+/// </summary>
+/// <param name="points">Support points to move on surface</param>
+/// <param name="mesh">Define surface for move points</param>
+/// <param name="throw_on_cancel">Call in meanwhile to check cancel event</param>
+/// <returns>Support points laying on mesh surface</returns>
+SupportPoints move_on_mesh_surface(
+    const LayerSupportPoints &points,
+    const AABBMesh &mesh,
+    double allowed_move,
+    ThrowOnCancel throw_on_cancel
+);
+
+}}
+
+#endif // SLA_SUPPORTPOINTGENERATOR_HPP

src/libslic3r/SLA/SupportPointGeneratorNew.cpp

@@ -1,382 +0,0 @@
-///|/ Copyright (c) Prusa Research 2024 Filip Sykala @Jony01
-///|/
-///|/ PrusaSlicer is released under the terms of the AGPLv3 or higher
-///|/
-
-#include "SupportPointGeneratorNew.hpp"
-
-#include <unordered_map> // point grid
-
-#include "libslic3r/Execution/ExecutionTBB.hpp" // parallel preparation of data for sampling
-#include "libslic3r/Execution/Execution.hpp"
-
-using namespace Slic3r;
-using namespace Slic3r::sla;
-
-namespace {
-
-/// <summary>
-/// Struct to store support points in 2d grid to faster search for nearest support points
-/// </summary>
-class Grid2D
-{
-    coord_t m_cell_size; // Squar: x and y are same
-    coord_t m_cell_size_half;
-    using Key = Point;
-    using Grid = std::unordered_multimap<Key, SupportPoint>;
-    Grid m_grid;
-
-public:
-    /// <summary>
-    /// Set cell size for grid
-    /// </summary>
-    /// <param name="cell_size">Granularity of stored points
-    /// Must be bigger than maximal used radius</param>
-    explicit Grid2D(const coord_t &cell_size)
-        : m_cell_size(cell_size), m_cell_size_half(cell_size / 2) {}
-
-    Key cell_id(const Point &point) const {
-        return Key(point.x() / m_cell_size, point.y() / m_cell_size);
-    }
-
-    void add(SupportPoint &&point) {
-        m_grid.emplace(cell_id(point.position_on_layer), std::move(point));
-    }
-
-    using CheckFnc = std::function<bool(const SupportPoint &, const Point&)>;
-    bool exist_true_in_4cell_neighbor(const Point &pos, const CheckFnc& fnc) const {
-        Key key = cell_id(pos);
-        if (exist_true_for_cell(key, pos, fnc)) return true;
-        Point un_cell_pos(
-            key.x() * m_cell_size + m_cell_size_half, 
-            key.y() * m_cell_size + m_cell_size_half );
-        Key key2(
-            (un_cell_pos.x() > pos.x()) ? key.x() + 1 : key.x() - 1,
-            (un_cell_pos.y() > pos.y()) ? key.y() + 1 : key.y() - 1);
-        if (exist_true_for_cell(key2, pos, fnc)) return true;
-        if (exist_true_for_cell({key.x(), key2.y()}, pos, fnc)) return true;
-        if (exist_true_for_cell({key2.x(), key.y()}, pos, fnc)) return true;
-        return false;
-    }
-
-    void merge(Grid2D &&grid) {
-        // support to merge only grid with same size
-        assert(m_cell_size == grid.m_cell_size);
-        m_grid.merge(std::move(grid.m_grid));
-    }
-
-    SupportPoints get_points() const { 
-        SupportPoints result;
-        result.reserve(m_grid.size());
-        for (const auto& [key, support] : m_grid)
-            result.push_back(support);
-        return result;
-    }
-private:
-    bool exist_true_for_cell(const Key &key, const Point &pos, const CheckFnc& fnc) const{
-        auto [begin_it, end_it] = m_grid.equal_range(key);
-        for (Grid::const_iterator it = begin_it; it != end_it; ++it) {
-            const SupportPoint &support_point = it->second;
-            if (fnc(support_point, pos))
-                return true;
-        }
-        return false;
-    }
-};
-
-/// <summary>
-/// Intersection of line segment and circle
-/// </summary>
-/// <param name="p1">Line segment point A, Point lay inside circle</param>
-/// <param name="p2">Line segment point B, Point lay outside or on circle</param>
-/// <param name="cnt">Circle center point</param>
-/// <param name="r2">squared value of Circle Radius (r2 = r*r)</param>
-/// <returns>Intersection point</returns>
-Point intersection(const Point &p1, const Point &p2, const Point &cnt, double r2) {
-    // Vector from p1 to p2
-    Vec2d dp_d((p2 - p1).cast<double>());
-    // Vector from circle center to p1
-    Vec2d f_d((p1 - cnt).cast<double>());
-
-    double a = dp_d.squaredNorm();
-    double b = 2 * (f_d.x() * dp_d.x() + f_d.y() * dp_d.y());
-    double c = f_d.squaredNorm() - r2;
-
-    // Discriminant of the quadratic equation
-    double discriminant = b * b - 4 * a * c;
-
-    // No intersection if discriminant is negative
-    assert(discriminant > 0);
-    if (discriminant < 0)
-        return {}; // No intersection
-
-    // Calculate the two possible values of t (parametric parameter)
-    discriminant = sqrt(discriminant);
-    double t1 = (-b - discriminant) / (2 * a);
-
-    // Check for valid intersection points within the line segment
-    if (t1 >= 0 && t1 <= 1) {
-        return {p1.x() + t1 * dp_d.x(), p1.y() + t1 * dp_d.y()};
-    }
-
-    // should not be in use
-    double t2 = (-b + discriminant) / (2 * a);
-    if (t2 >= 0 && t2 <= 1 && t1 != t2) {
-        return {p1.x() + t2 * dp_d.x(), p1.y() + t2 * dp_d.y()};
-    }
-    return {};
-}
-
-/// <summary>
-/// Uniformly sample Polygon,
-/// Use first point and each next point is first crosing radius from last added
-/// </summary>
-/// <param name="p">Polygon to sample</param>
-/// <param name="dist2">Squared distance for sampling</param>
-/// <returns>Uniformly distributed points laying on input polygon
-/// with exception of first and last point(they are closer than dist2)</returns>
-Slic3r::Points sample(const Polygon &p, double dist2) {
-    if (p.empty())
-        return {};
-
-    Slic3r::Points r;
-    r.push_back(p.front());
-    const Point *prev_pt = nullptr;
-    for (size_t prev_i = 0; prev_i < p.size(); prev_i++) {
-        size_t curr_i = (prev_i != p.size() - 1) ? prev_i + 1 : 0;
-        const Point &pt = p.points[curr_i];
-        double p_dist2 = (r.back() - pt).cast<double>().squaredNorm();
-        while (p_dist2 > dist2) { // line segment goes out of radius
-            if (prev_pt == nullptr)
-                prev_pt = &p.points[prev_i];
-            r.push_back(intersection(*prev_pt, pt, r.back(), dist2));
-            p_dist2 = (r.back() - pt).cast<double>().squaredNorm();
-            prev_pt = &r.back();
-        }
-        prev_pt = nullptr;
-    }
-    return r;
-}
-
-coord_t get_supported_radius(const SupportPoint &p, float z_distance, const SupportPointGeneratorConfig &config
-) {
-    // TODO: calculate support radius
-    return scale_(5.);
-}
-
-void sample_part(
-    const LayerPart &part,
-    size_t layer_id,
-    const SupportPointGeneratorData &data,
-    const SupportPointGeneratorConfig &config,
-    std::vector<Grid2D> &grids,
-    std::vector<Grid2D> &prev_grids
-) {
-    // NOTE: first layer do not have prev part
-    assert(layer_id != 0);
-
-    const Layers &layers = data.layers;
-    const LayerParts &prev_layer_parts = layers[layer_id - 1].parts;
-    const LayerParts::const_iterator &prev_part_it = part.prev_parts.front().part_it;
-    size_t index_of_prev_part = prev_part_it - prev_layer_parts.begin();
-    if (prev_part_it->next_parts.size() == 1) {
-        grids.push_back(std::move(prev_grids[index_of_prev_part]));
-    } else { // Need a copy there are multiple parts above previus one
-        grids.push_back(prev_grids[index_of_prev_part]); // copy
-    }
-    // current part grid
-    Grid2D &part_grid = grids.back();
-
-    // merge other grid in case of multiple previous parts
-    for (size_t i = 1; i < part.prev_parts.size(); ++i) {
-        const LayerParts::const_iterator &prev_part_it = part.prev_parts[i].part_it;
-        size_t index_of_prev_part = prev_part_it - prev_layer_parts.begin();
-        if (prev_part_it->next_parts.size() == 1) {
-            part_grid.merge(std::move(prev_grids[index_of_prev_part]));
-        } else { // Need a copy there are multiple parts above previus one
-            Grid2D grid_ = prev_grids[index_of_prev_part]; // copy
-            part_grid.merge(std::move(grid_));
-        }
-    }
-
-    float part_height = data.heights[layer_id];
-    Grid2D::CheckFnc is_supported = [part_height, &config]
-    (const SupportPoint &support_point, const Point &p) -> bool {
-        float diff_height = part_height - support_point.z_height;
-        coord_t r_ = get_supported_radius(support_point, diff_height, config);
-        Point dp = support_point.position_on_layer - p;
-        if (std::abs(dp.x()) > r_) return false;
-        if (std::abs(dp.y()) > r_) return false;
-        double r2 = static_cast<double>(r_);
-        r2 *= r2;
-        return dp.cast<double>().squaredNorm() < r2;
-    };
-
-    // check distance to nearest support points from grid
-    float maximal_radius = scale_(5.f);
-    for (const Point &p : part.samples) {
-        if (!part_grid.exist_true_in_4cell_neighbor(p, is_supported)) {
-            // not supported sample, soo create new support point
-            part_grid.add(SupportPoint{
-                /* head_front_radius */ 0.4,
-                SupportPointType::slope,
-                &part,
-                /* position_on_layer */ p,
-                part_height,
-                /* direction_to_mass */ Point(1,0)
-                });
-        }    
-    }
-}
-
-Points uniformly_sample(const ExPolygon &island, const SupportPointGeneratorConfig &cfg) {
-    // TODO: Implement it
-    return Points{island.contour.centroid()};
-}
-
-Grid2D support_island(const LayerPart &part, float part_z, const SupportPointGeneratorConfig &cfg) {
-    // Maximal radius of supported area of one support point
-    double max_support_radius = 10.; // cfg.cell_size;
-
-    // maximal radius of support
-    coord_t cell_size = scale_(max_support_radius);
-
-    Grid2D part_grid(cell_size);
-    Points pts = uniformly_sample(*part.shape, cfg);
-    for (const Point &pt : pts)
-        part_grid.add(SupportPoint{
-            /* head_front_radius */ 0.4,
-            SupportPointType::island,
-            &part,
-            /* position_on_layer */ pt,
-            part_z,
-            /* direction_to_mass */ Point(0,0) // from bottom
-        });
-}
-
-}; 
-
-SupportPointGeneratorData Slic3r::sla::prepare_generator_data(
-    std::vector<ExPolygons> &&slices,
-    std::vector<float> &&heights,
-    ThrowOnCancel throw_on_cancel,
-    StatusFunction statusfn
-) {
-    // check input
-    assert(!slices.empty());
-    assert(slices.size() == heights.size());
-    if (slices.empty() || slices.size() != heights.size())
-        return SupportPointGeneratorData{};
-
-    // Move input into result
-    SupportPointGeneratorData result;
-    result.slices = std::move(slices);
-    result.heights = std::move(heights);
-
-    // Allocate empty layers.
-    result.layers = Layers(result.slices.size(), {});
-
-    // Generate Extents and SampleLayers
-    execution::for_each(ex_tbb, size_t(0), result.slices.size(),
-        [&result, throw_on_cancel](size_t layer_id) {
-        if ((layer_id % 8) == 0)
-            // Don't call the following function too often as it flushes
-            // CPU write caches due to synchronization primitves.
-            throw_on_cancel();
-
-        const double sample_distance_in_mm = scale_(2);
-        const double sample_distance_in_mm2 = sample_distance_in_mm * sample_distance_in_mm;
-
-        Layer &layer = result.layers[layer_id];
-        const ExPolygons &islands = result.slices[layer_id];
-        layer.parts.reserve(islands.size());
-        for (const ExPolygon &island : islands)                        
-            layer.parts.push_back(LayerPart{
-                &island, 
-                get_extents(island.contour), 
-                sample(island.contour, sample_distance_in_mm2)
-            });
-        
-    }, 32 /*gransize*/);
-
-    // Link parts by intersections
-    execution::for_each(ex_tbb, size_t(1), result.slices.size(),
-                      [&result, throw_on_cancel] (size_t layer_id) {
-        if ((layer_id % 2) == 0)
-            // Don't call the following function too often as it flushes CPU write caches due to synchronization primitves.
-            throw_on_cancel();
-
-        LayerParts &parts_above = result.layers[layer_id].parts;
-        LayerParts &parts_below = result.layers[layer_id-1].parts;
-        for (auto it_above = parts_above.begin(); it_above < parts_above.end(); ++it_above) {
-            for (auto it_below = parts_below.begin(); it_below < parts_below.end(); ++it_below) {
-                // Improve: do some sort of parts + skip some of them
-                if (!it_above->shape_extent.overlap(it_below->shape_extent))
-                    continue; // no bounding box overlap
-
-                // Improve: test could be done faster way
-                Polygons polys = intersection(*it_above->shape, *it_below->shape);
-                if (polys.empty())
-                    continue; // no intersection
-
-                // TODO: check minimal intersection!
-
-                it_above->prev_parts.emplace_back(PartLink{it_below});
-                it_below->next_parts.emplace_back(PartLink{it_above});
-            }
-        }
-    }, 8 /* gransize */);
-    return result;
-}
-
-SupportPoints Slic3r::sla::generate_support_points(
-    const SupportPointGeneratorData &data,
-    const SupportPointGeneratorConfig &config,
-    ThrowOnCancel throw_on_cancel,
-    StatusFunction statusfn
-){
-    const Layers &layers = data.layers;
-    double increment = 100.0 / static_cast<double>(layers.size());
-    double status = 0; // current progress
-    int status_int = 0; 
-
-    SupportPoints result;
-    std::vector<Grid2D> prev_grids; // same count as previous layer item size
-    for (size_t layer_id = 0; layer_id < layers.size(); ++layer_id) {
-        const Layer &layer = layers[layer_id];
-
-        std::vector<Grid2D> grids;
-        grids.reserve(layer.parts.size());
-        
-        for (const LayerPart &part : layer.parts) {
-            if (part.prev_parts.empty()) {
-                // new island - needs support no doubt
-                float part_z = data.heights[layer_id];
-                grids.push_back(support_island(part, part_z, config));
-            } else {
-                sample_part(part, layer_id, data, config, grids, prev_grids);
-            }
-
-            // collect result from grid of top part
-            if (part.next_parts.empty()) {
-                const Grid2D &part_grid = grids.back();
-                SupportPoints sps = part_grid.get_points();
-                result.insert(result.end(), 
-                    std::make_move_iterator(sps.begin()),
-                    std::make_move_iterator(sps.end()));
-            }
-        }
-        prev_grids = std::move(grids);
-
-        throw_on_cancel();
-
-        int old_status_int = status_int;
-        status += increment;
-        status_int = static_cast<int>(std::round(status));
-        if (old_status_int < status_int)
-            statusfn(status_int);
-    }
-    return result;
-}
-
-

src/libslic3r/SLA/SupportPointGeneratorNew.hpp

@@ -1,190 +0,0 @@
-///|/ Copyright (c) Prusa Research 2024 Filip Sykala @Jony01
-///|/
-///|/ PrusaSlicer is released under the terms of the AGPLv3 or higher
-///|/
-#ifndef SLA_SUPPORTPOINTGENERATOR_NEW_HPP
-#define SLA_SUPPORTPOINTGENERATOR_NEW_HPP
-
-#include <vector>
-#include <functional>
-
-#include <boost/container/small_vector.hpp>
-
-#include "libslic3r/Point.hpp"
-#include "libslic3r/ExPolygon.hpp"
-
-namespace Slic3r::sla {
-
-/// <summary>
-/// Configuration for automatic support placement
-/// </summary>
-struct SupportPointGeneratorConfig{
-    /// <summary>
-    /// 0 mean only one support point for each island
-    /// lower than one mean less amount of support points
-    /// 1 mean fine tuned sampling
-    /// more than one mean bigger amout of support points
-    /// </summary>
-    float density_relative{1.f};
-
-    /// <summary>
-    /// Size range for support point interface (head)
-    /// </summary>
-    MinMax<float> head_diameter = {0.2f, 0.6f}; // [in mm]
-
-    // FIXME: calculate actual pixel area from printer config:
-    // const float pixel_area =
-    // pow(wxGetApp().preset_bundle->project_config.option<ConfigOptionFloat>("display_width") /
-    // wxGetApp().preset_bundle->project_config.option<ConfigOptionInt>("display_pixels_x"), 2.f); //
-    // Minimal island Area to print - TODO: Should be modifiable from UI
-    // !! Filter should be out of sampling algorithm !!
-    float minimal_island_area = pow(0.047f, 2.f); // [in mm^2] pixel_area
-};
-
-struct LayerPart; // forward decl.
-using LayerParts = std::vector<LayerPart>;
-
-struct PartLink
-{
-    LayerParts::const_iterator part_it;
-    // float overlap_area; // sum of overlap areas
-    // ExPolygons overlap; // clipper intersection_ex
-    // ExPolygons overhang; // clipper diff_ex
-};
-#ifdef NDEBUG
-// In release mode, use the optimized container.
-using PartLinks = boost::container::small_vector<PartLink, 4>;
-#else
-// In debug mode, use the standard vector, which is well handled by debugger visualizer.
-using PartLinks = std::vector<PartLink>;
-#endif
-
-// Part on layer is defined by its shape 
-struct LayerPart {
-    // Pointer to expolygon stored in input
-    const ExPolygon *shape;
-
-    // rectangular bounding box of shape
-    BoundingBox shape_extent;
-
-    // uniformly sampled shape contour
-    Slic3r::Points samples;
-    // IMPROVE: sample only overhangs part of shape
-
-    // Parts from previous printed layer, which is connected to current part
-    PartLinks prev_parts;
-    PartLinks next_parts;
-};
-
-/// <summary>
-/// One slice divided into 
-/// </summary>
-struct Layer
-{
-    // index into parent Layesr + heights + slices 
-    // [[deprecated]] Use index to layers insted of adress from item
-    size_t layer_id;
-
-    // Absolute distance from Zero - copy value from heights<float>
-    // [[deprecated]] Use index to layers insted of adress from item
-    double print_z; // [in mm]
-
-    // data for one expolygon
-    LayerParts parts;
-};
-using Layers = std::vector<Layer>;
-
-/// <summary>
-/// Keep state of Support Point generation
-/// Used for resampling with different configuration
-/// </summary>
-struct SupportPointGeneratorData
-{
-    // Input slices of mesh
-    std::vector<ExPolygons> slices;
-    // Same size as slices
-    std::vector<float> heights;
-
-    // link to slices
-    Layers layers;
-};
-
-// Reason of automatic support placement usage
-enum class SupportPointType {
-    manual_add,
-    island, // no move
-    slope,
-    thin,
-    stability,
-    edge
-};
-
-/// <summary>
-/// Generated support point
-/// </summary>
-struct SupportPoint
-{
-    // radius of the touching interface
-    // Also define force it must keep
-    float head_front_radius{1.f};
-
-    // type
-    SupportPointType type{SupportPointType::manual_add};
-
-    // Pointer on source ExPolygon otherwise nullptr
-    const LayerPart *part{nullptr}; 
-
-    // 2d coordinate on layer
-    // use only when part is not nullptr
-    Point position_on_layer; // [scaled_ unit]
-
-    // height of part
-    float z_height;
-
-    // 2d direction into expolygon mass
-    // used as ray to positioning point on mesh surface
-    Point direction_to_mass;
-};
-using SupportPoints = std::vector<SupportPoint>;
-
-// call during generation of support points to check cancel event
-using ThrowOnCancel = std::function<void(void)>;
-// call to say progress of generation into gui in range from 0 to 100
-using StatusFunction= std::function<void(int)>;
-
-/// <summary>
-/// Prepare data for generate support points
-/// Used for interactive resampling to store permanent data between configuration changes.,
-/// Everything which could be prepared are stored into result.
-/// Need to regenerate on mesh change(Should be connected with ObjectId) OR change of slicing heights
-/// </summary>
-/// <param name="slices">Countour cut from mesh</param>
-/// <param name="heights">Heights of the slices - Same size as slices</param>
-/// <param name="throw_on_cancel">Call in meanwhile to check cancel event</param>
-/// <param name="statusfn">Say progress of generation into gui</param>
-/// <returns>Data prepared for generate support points</returns>
-SupportPointGeneratorData prepare_generator_data(
-    std::vector<ExPolygons> &&slices,
-    std::vector<float> &&heights,
-    ThrowOnCancel throw_on_cancel,
-    StatusFunction statusfn
-);
-
-/// <summary>
-/// Generate support points on islands by configuration parameters
-/// </summary>
-/// <param name="data">Preprocessed data needed for sampling</param>
-/// <param name="config">Define density of samples</param>
-/// <param name="throw_on_cancel">Call in meanwhile to check cancel event</param>
-/// <param name="statusfn">Progress of generation into gui</param>
-/// <returns>Generated support points</returns>
-SupportPoints generate_support_points(
-    const SupportPointGeneratorData &data,
-    const SupportPointGeneratorConfig &config,
-    ThrowOnCancel throw_on_cancel,
-    StatusFunction statusfn
-);
-
-} // namespace Slic3r::sla
-
-#endif // SLA_SUPPORTPOINTGENERATOR_NEW_HPP

src/libslic3r/SLAPrint.cpp

@@ -1255,8 +1255,12 @@ SLAPrintObject::get_parts_to_slice(SLAPrintObjectStep untilstep) const
 sla::SupportPoints SLAPrintObject::transformed_support_points() const
 {
     assert(model_object());
-
+    auto spts = model_object()->sla_support_points;
-    return sla::transformed_support_points(*model_object(), trafo());
+    Transform3f tr = trafo().cast<float>();
+    for (sla::SupportPoint &suppt : spts) {
+        suppt.pos = tr * suppt.pos;
+    }
+    return spts;
 }
 
 sla::DrainHoles SLAPrintObject::transformed_drainhole_points() const

src/libslic3r/SLAPrintSteps.cpp

@@ -51,7 +51,6 @@
 #include "libslic3r/SLA/Hollowing.hpp"
 #include "libslic3r/SLA/JobController.hpp"
 #include "libslic3r/SLA/RasterBase.hpp"
-#include "libslic3r/SLA/SupportPoint.hpp"
 #include "libslic3r/SLA/SupportTree.hpp"
 #include "libslic3r/SLA/SupportTreeStrategies.hpp"
 #include "libslic3r/SLAPrint.hpp"
@@ -632,24 +631,20 @@ void SLAPrint::Steps::support_points(SLAPrintObject &po)
     // we will do the autoplacement. Otherwise we will just blindly copy the
     // frontend data into the backend cache.
     if (mo.sla_points_status != sla::PointsStatus::UserModified) {
-
-        // calculate heights of slices (slices are calculated already)
-        const std::vector<float>& heights = po.m_model_height_levels;
-
         throw_if_canceled();
-        sla::SupportPointGenerator::Config config;
+        sla::SupportPointGeneratorConfig config;
         const SLAPrintObjectConfig& cfg = po.config();
 
         // the density config value is in percents:
         config.density_relative = float(cfg.support_points_density_relative / 100.f);
-        config.minimal_distance = float(cfg.support_points_minimal_distance);
+        
         switch (cfg.support_tree_type) {
         case sla::SupportTreeType::Default:
         case sla::SupportTreeType::Organic:
-            config.head_diameter = float(cfg.support_head_front_diameter);
+            config.head_diameter = {float(cfg.support_head_front_diameter), .0};
             break;
         case sla::SupportTreeType::Branching:
-            config.head_diameter = float(cfg.branchingsupport_head_front_diameter);
+            config.head_diameter = {float(cfg.branchingsupport_head_front_diameter), .0};
             break;
         }
 
@@ -666,12 +661,29 @@ void SLAPrint::Steps::support_points(SLAPrintObject &po)
 
         // Construction of this object does the calculation.
         throw_if_canceled();
-        sla::SupportPointGenerator auto_supports(
-            po.m_supportdata->input.emesh, po.get_model_slices(),
-            heights, config, [this]() { throw_if_canceled(); }, statuscb);
 
-        // Now let's extract the result.
+        // TODO: filter small unprintable islands in slices
-        std::vector<sla::SupportPoint>& points = auto_supports.output();
+        // (Island with area smaller than 1 pixel was skipped in support generator)
+
+        std::vector<ExPolygons> slices = po.get_model_slices(); // copy
+        std::vector<float> heights = po.m_model_height_levels; // copy
+        sla::ThrowOnCancel cancel = [this]() { throw_if_canceled(); };
+        sla::StatusFunction status = statuscb;
+        sla::SupportPointGeneratorData data = 
+            sla::prepare_generator_data(std::move(slices), std::move(heights), cancel, status);
+
+        sla::LayerSupportPoints layer_support_points = 
+            sla::generate_support_points(data, config, cancel, status);
+
+        const AABBMesh& emesh = po.m_supportdata->input.emesh;
+        // Maximal move of support point to mesh surface,
+        // no more than height of layer
+        assert(po.m_model_height_levels.size() > 1);
+        double allowed_move = (po.m_model_height_levels[1] - po.m_model_height_levels[0]) +
+            std::numeric_limits<float>::epsilon();
+        sla::SupportPoints support_points = 
+            sla::move_on_mesh_surface(layer_support_points, emesh, allowed_move, cancel);
+
         throw_if_canceled();
 
         MeshSlicingParamsEx params;
@@ -691,9 +703,9 @@ void SLAPrint::Steps::support_points(SLAPrintObject &po)
                           });
 
         SuppPtMask mask{blockers, enforcers, po.config().support_enforcers_only.getBool()};
-        filter_support_points_by_modifiers(points, mask, po.m_model_height_levels);
+        filter_support_points_by_modifiers(support_points, mask, po.m_model_height_levels);
 
-        po.m_supportdata->input.pts = points;
+        po.m_supportdata->input.pts = support_points;
 
         BOOST_LOG_TRIVIAL(debug)
             << "Automatic support points: "
@@ -717,10 +729,17 @@ void SLAPrint::Steps::support_tree(SLAPrintObject &po)
     // If the zero elevation mode is engaged, we have to filter out all the
     // points that are on the bottom of the object
     if (is_zero_elevation(po.config())) {
-        remove_bottom_points(po.m_supportdata->input.pts,
+        // remove_bottom_points
-                             float(
+        std::vector<sla::SupportPoint> &pts = po.m_supportdata->input.pts;
-                                 po.m_supportdata->input.zoffset +
+        float lvl(po.m_supportdata->input.zoffset + EPSILON); 
-                                 EPSILON));
+
+        // get iterator to the reorganized vector end
+        auto endit = std::remove_if(pts.begin(), pts.end(), 
+            [lvl](const sla::SupportPoint &sp) {
+                return sp.pos.z() <= lvl; });
+
+        // erase all elements after the new end
+        pts.erase(endit, pts.end());
     }
 
     po.m_supportdata->input.cfg = make_support_cfg(po.m_config);

src/slic3r/GUI/Gizmos/GLGizmoSlaSupports.cpp

@@ -212,7 +212,7 @@ void GLGizmoSlaSupports::render_points(const Selection& selection)
         if (size_t(m_hover_id) == i && m_editing_mode) // ignore hover state unless editing mode is active
             render_color = { 0.f, 1.f, 1.f, 1.f };
         else { // neigher hover nor picking
-            bool supports_new_island = m_lock_unique_islands && support_point.is_new_island;
+            bool supports_new_island = m_lock_unique_islands && support_point.type == sla::SupportPointType::island;
             if (m_editing_mode) {
                 if (point_selected)
                     render_color = { 1.f, 0.3f, 0.3f, 1.f};
@@ -324,7 +324,7 @@ bool GLGizmoSlaSupports::gizmo_event(SLAGizmoEventType action, const Vec2d& mous
                 std::pair<Vec3f, Vec3f> pos_and_normal;
                 if (unproject_on_mesh(mouse_position, pos_and_normal)) { // we got an intersection
                     Plater::TakeSnapshot snapshot(wxGetApp().plater(), _L("Add support point"));
-                    m_editing_cache.emplace_back(sla::SupportPoint(pos_and_normal.first, m_new_point_head_diameter/2.f, false), false, pos_and_normal.second);
+                    m_editing_cache.emplace_back(sla::SupportPoint{pos_and_normal.first, m_new_point_head_diameter/2.f}, false, pos_and_normal.second);
                     m_parent.set_as_dirty();
                     m_wait_for_up_event = true;
                     unregister_point_raycasters_for_picking();
@@ -479,7 +479,7 @@ void GLGizmoSlaSupports::delete_selected_points(bool force)
     Plater::TakeSnapshot snapshot(wxGetApp().plater(), _L("Delete support point"));
 
     for (unsigned int idx=0; idx<m_editing_cache.size(); ++idx) {
-        if (m_editing_cache[idx].selected && (!m_editing_cache[idx].support_point.is_new_island || !m_lock_unique_islands || force)) {
+        if (m_editing_cache[idx].selected && (!m_editing_cache[idx].support_point.is_island() || !m_lock_unique_islands || force)) {
             m_editing_cache.erase(m_editing_cache.begin() + (idx--));
         }
     }
@@ -914,7 +914,7 @@ void GLGizmoSlaSupports::on_dragging(const UpdateData &data)
 {
     assert(m_hover_id != -1);
     if (!m_editing_mode) return;
-    if (m_editing_cache[m_hover_id].support_point.is_new_island && m_lock_unique_islands)
+    if (m_editing_cache[m_hover_id].support_point.is_island() && m_lock_unique_islands)
         return;
     
     std::pair<Vec3f, Vec3f> pos_and_normal;
@@ -922,7 +922,7 @@ void GLGizmoSlaSupports::on_dragging(const UpdateData &data)
         return;
 
     m_editing_cache[m_hover_id].support_point.pos = pos_and_normal.first;
-    m_editing_cache[m_hover_id].support_point.is_new_island = false;
+    m_editing_cache[m_hover_id].support_point.type = sla::SupportPointType::manual_add;
     m_editing_cache[m_hover_id].normal = pos_and_normal.second;        
 }
 
@@ -1124,7 +1124,7 @@ void GLGizmoSlaSupports::get_data_from_backend()
             const std::vector<sla::SupportPoint>& points = po->get_support_points();
             auto mat = po->trafo().inverse().cast<float>();
             for (unsigned int i=0; i<points.size();++i)
-                m_normal_cache.emplace_back(sla::SupportPoint(mat * points[i].pos, points[i].head_front_radius, points[i].is_new_island));
+                m_normal_cache.emplace_back(sla::SupportPoint{mat * points[i].pos, points[i].head_front_radius});
 
             mo->sla_points_status = sla::PointsStatus::AutoGenerated;
             break;