improved triangle tracking in triangle selector - if not hit registered, nearest triangle is taken instead

src/libslic3r/SupportSpotsGenerator.cpp

@@ -119,7 +119,6 @@ public:
 
 class StabilityAccumulator {
 private:
-    Polygon base_convex_hull { };
     Points support_points { };
     Vec3f centroid_accumulator = Vec3f::Zero();
     float accumulated_volume { };
@@ -384,7 +383,7 @@ void check_extrusion_entity_stability(const ExtrusionEntity *entity,
                 if (distance_from_last_support_point > params.min_distance_between_support_points &&
                         bridging_acc.distance // if unsupported distance is larger than bridge distance linearly decreased by curvature, enforce supports.
                         > params.bridge_distance
-                                / (bridging_acc.max_curvature
+                                / (1.0f + bridging_acc.max_curvature
                                         * params.bridge_distance_decrease_by_curvature_factor / PI)) {
                     current_segment.add_support_point(current, 0.0f); // Do not count extrusion supports into the sticking force. They can be very densely placed, causing algorithm to overestimate stickiness.
                     issues.supports_nedded.emplace_back(to_vec3f(current), 1.0);

src/libslic3r/SupportSpotsGenerator.hpp

@@ -11,7 +11,7 @@ struct Params {
     const float gravity_constant = 9806.65f; // mm/s^2; gravity acceleration on Earth's surface, algorithm assumes that printer is in upwards position.
 
     float bridge_distance = 10.0f; //mm
-    float bridge_distance_decrease_by_curvature_factor = 5.0f; // >0 REQUIRED; allowed bridge distance = bridge_distance / (this factor * (curvature / PI) )
+    float bridge_distance_decrease_by_curvature_factor = 5.0f; // allowed bridge distance = bridge_distance / (this factor * (curvature / PI) )
 
     float min_distance_between_support_points = 0.5f;
 
@@ -21,7 +21,7 @@ struct Params {
 
     float support_points_interface_radius = 0.5f; // mm
 
-    float max_acceleration = 1000.0f; // mm/s^2 ; max acceleration of object (bed) in XY
+    float max_acceleration = 9*1000.0f; // mm/s^2 ; max acceleration of object (bed) in XY (NOTE: The max hit is received by the object in the jerk phase, so the usual machine limits are too low)
     float filament_density = 1.25f * 0.001f; // g/mm^3  ; Common filaments are very lightweight, so precise number is not that important
 
     float tolerable_extruder_conflict_force = 50.0f * gravity_constant; // force that can occasionally push the model due to various factors (filament leaks, small curling, ... ); current value corresponds to weight of X grams

src/libslic3r/TriangleSelectorWrapper.cpp

@@ -29,6 +29,14 @@ void TriangleSelectorWrapper::enforce_spot(const Vec3f &point, const Vec3f &orig
                 break;
             }
         }
+    } else {
+        size_t hit_idx_out;
+        Vec3f hit_point_out;
+        AABBTreeIndirect::squared_distance_to_indexed_triangle_set(mesh.its.vertices, mesh.its.indices, triangles_tree, point, hit_idx_out, hit_point_out);
+        std::unique_ptr<TriangleSelector::Cursor> cursor = std::make_unique<TriangleSelector::Sphere>(
+                point, origin, radius, Transform3d::Identity(), TriangleSelector::ClippingPlane { });
+        selector.select_patch(hit_idx_out, std::move(cursor), EnforcerBlockerType::ENFORCER, Transform3d::Identity(),
+                true, 0.0f);
     }
 }