WIP: Support of SLA suport & pad GLVolumes, couple of fixes.

src/libslic3r/SLAPrint.cpp

@@ -79,7 +79,7 @@ SLAPrint::ApplyStatus SLAPrint::apply(const Model &model,
 
     // Grab the lock for the Print / PrintObject milestones.
 	tbb::mutex::scoped_lock lock(this->state_mutex());
-    if(m_objects.empty() && model.objects.empty())
+	if (m_objects.empty() && model.objects.empty() && m_model.objects.empty())
         return APPLY_STATUS_UNCHANGED;
 
     // Temporary: just to have to correct layer height for the rasterization
@@ -437,6 +437,32 @@ SLAPrintObject::SLAPrintObject(SLAPrint *print, ModelObject *model_object):
 
 SLAPrintObject::~SLAPrintObject() {}
 
+bool SLAPrintObject::has_mesh(SLAPrintObjectStep step) const
+{
+    switch (step) {
+    case slaposSupportTree:
+//        return m_supportdata && m_supportdata->support_tree_ptr && ! m_supportdata->support_tree_ptr->get().merged_mesh().empty();
+		return ! this->support_mesh().empty();
+    case slaposBasePool:
+//		return m_supportdata && m_supportdata->support_tree_ptr && ! m_supportdata->support_tree_ptr->get_pad().empty();
+		return ! this->pad_mesh().empty();
+	default:
+        return false;
+    }
+}
+
+TriangleMesh SLAPrintObject::get_mesh(SLAPrintObjectStep step) const
+{
+	switch (step) {
+	case slaposSupportTree:
+		return this->support_mesh();
+	case slaposBasePool:
+		return this->pad_mesh();
+	default:
+		return TriangleMesh();
+	}
+}
+
 TriangleMesh SLAPrintObject::support_mesh() const
 {
     TriangleMesh trm;

src/libslic3r/SLAPrint.hpp

@@ -48,6 +48,9 @@ public:
 	};
     const std::vector<Instance>& instances() const { return m_instances; }
 
+    bool                    has_mesh(SLAPrintObjectStep step) const;
+    TriangleMesh            get_mesh(SLAPrintObjectStep step) const;
+
     // Get a support mesh centered around origin in XY, and with zero rotation around Z applied.
     // Support mesh is only valid if this->is_step_done(slaposSupportTree) is true.
     TriangleMesh            support_mesh() const;

src/libslic3r/TriangleMesh.cpp

@@ -521,6 +521,7 @@ BoundingBoxf3 TriangleMesh::transformed_bounding_box(const Transform3d& t) const
 
     if (stl.stats.shared_vertices > 0)
     {
+		assert(stl.v_shared != nullptr);
         stl_vertex* vertex_ptr = stl.v_shared;
         for (int i = 0; i < stl.stats.shared_vertices; ++i)
         {

src/libslic3r/TriangleMesh.hpp

@@ -65,6 +65,7 @@ public:
     void reset_repair_stats();
     bool needed_repair() const;
     size_t facets_count() const { return this->stl.stats.number_of_facets; }
+    bool   empty() const { return this->facets_count() == 0; }
 
     // Returns true, if there are two and more connected patches in the mesh.
     // Returns false, if one or zero connected patch is in the mesh.

src/slic3r/GUI/3DScene.cpp

@@ -216,6 +216,7 @@ GLVolume::GLVolume(float r, float g, float b, float a)
 #endif // ENABLE_MODELVOLUME_TRANSFORM
     , m_transformed_convex_hull_bounding_box_dirty(true)
     , m_convex_hull(nullptr)
+    , m_convex_hull_owned(false)
     // geometry_id == 0 -> invalid
     , geometry_id(std::pair<size_t, size_t>(0, 0))
     , extruder_id(0)
@@ -239,6 +240,12 @@ GLVolume::GLVolume(float r, float g, float b, float a)
     set_render_color(r, g, b, a);
 }
 
+GLVolume::~GLVolume()
+{
+    if (m_convex_hull_owned)
+        delete m_convex_hull;
+}
+
 void GLVolume::set_render_color(float r, float g, float b, float a)
 {
     render_color[0] = r;
@@ -365,9 +372,10 @@ void GLVolume::set_mirror(Axis axis, double mirror)
 }
 #endif // !ENABLE_MODELVOLUME_TRANSFORM
 
-void GLVolume::set_convex_hull(const TriangleMesh& convex_hull)
+void GLVolume::set_convex_hull(const TriangleMesh *convex_hull, bool owned)
 {
-    m_convex_hull = &convex_hull;
+    m_convex_hull = convex_hull;
+    m_convex_hull_owned = owned;
 }
 
 #if !ENABLE_MODELVOLUME_TRANSFORM
@@ -779,7 +787,8 @@ int GLVolumeCollection::load_object_volume(
 	v.composite_id = GLVolume::CompositeID(obj_idx, volume_idx, instance_idx);
     if (model_volume->is_model_part())
     {
-        v.set_convex_hull(model_volume->get_convex_hull());
+		// GLVolume will reference a convex hull from model_volume!
+        v.set_convex_hull(&model_volume->get_convex_hull(), false);
         if (extruder_id != -1)
             v.extruder_id = extruder_id;
         v.layer_height_texture = layer_height_texture;
@@ -808,6 +817,8 @@ void GLVolumeCollection::load_object_auxiliary(
     // pairs of <instance_idx, print_instance_idx>
     const std::vector<std::pair<size_t, size_t>> &instances,
     SLAPrintObjectStep              milestone,
+    // Timestamp of the last change of the milestone
+    size_t                          timestamp,
     bool                            use_VBOs)
 {
     assert(print_object->is_step_done(milestone));
@@ -835,7 +846,9 @@ void GLVolumeCollection::load_object_auxiliary(
         v.bounding_box = v.indexed_vertex_array.bounding_box();
         v.indexed_vertex_array.finalize_geometry(use_VBOs);
 		v.composite_id = GLVolume::CompositeID(obj_idx, -1, (int)instance_idx.first);
-		v.set_convex_hull(convex_hull);
+        v.geometry_id = std::pair<size_t, size_t>(timestamp, model_instance.id().id);
+		// Create a copy of the convex hull mesh for each instance. Use a move operator on the last instance.
+		v.set_convex_hull((&instance_idx == &instances.back()) ? new TriangleMesh(std::move(convex_hull)) : new TriangleMesh(convex_hull), true);
         v.is_modifier  = false;
         v.shader_outside_printer_detection_enabled = true;
         //FIXME adjust with print_instance?

src/slic3r/GUI/3DScene.hpp

@@ -256,6 +256,7 @@ public:
 
     GLVolume(float r = 1.f, float g = 1.f, float b = 1.f, float a = 1.f);
     GLVolume(const float *rgba) : GLVolume(rgba[0], rgba[1], rgba[2], rgba[3]) {}
+    ~GLVolume();
 
 private:
 #if ENABLE_MODELVOLUME_TRANSFORM
@@ -280,7 +281,9 @@ private:
     // Whether or not is needed to recalculate the transformed bounding box.
     mutable bool          m_transformed_bounding_box_dirty;
     // Pointer to convex hull of the original mesh, if any.
+    // This object may or may not own the convex hull instance based on m_convex_hull_owned
     const TriangleMesh*   m_convex_hull;
+    bool                  m_convex_hull_owned;
     // Bounding box of this volume, in unscaled coordinates.
     mutable BoundingBoxf3 m_transformed_convex_hull_bounding_box;
     // Whether or not is needed to recalculate the transformed convex hull bounding box.
@@ -422,7 +425,7 @@ public:
     void set_offset(const Vec3d& offset);
 #endif // ENABLE_MODELVOLUME_TRANSFORM
 
-    void set_convex_hull(const TriangleMesh& convex_hull);
+    void set_convex_hull(const TriangleMesh *convex_hull, bool owned);
 
     int                 object_idx() const { return this->composite_id.object_id; }
     int                 volume_idx() const { return this->composite_id.volume_id; }
@@ -525,6 +528,8 @@ public:
         // pairs of <instance_idx, print_instance_idx>
         const std::vector<std::pair<size_t, size_t>> &instances,
         SLAPrintObjectStep              milestone,
+        // Timestamp of the last change of the milestone
+        size_t                          timestamp,
         bool                            use_VBOs);
 
     int load_wipe_tower_preview(

src/slic3r/GUI/GLCanvas3D.cpp

@@ -1867,7 +1867,10 @@ void GLCanvas3D::Selection::erase()
         for (unsigned int i : m_list)
         {
             const GLVolume* v = (*m_volumes)[i];
-            volumes_idxs.insert(std::make_pair(v->object_idx(), v->volume_idx()));
+			// Only remove volumes associated with ModelVolumes from the object list.
+			// Temporary meshes (SLA supports or pads) are not managed by the object list.
+			if (v->volume_idx() >= 0)
+	            volumes_idxs.insert(std::make_pair(v->object_idx(), v->volume_idx()));
         }
 
         std::vector<ItemForDelete> items;
@@ -3803,9 +3806,15 @@ void GLCanvas3D::reload_scene(bool force)
                 SLASupportState state;
 				for (size_t istep = 0; istep < sla_steps.size(); ++ istep) {
 					state.step[istep] = print_object->step_state_with_timestamp(sla_steps[istep]);
-					if (state.step[istep].state == PrintStateBase::DONE)
+					if (state.step[istep].state == PrintStateBase::DONE) {
-						for (const ModelInstance *model_instance : print_object->model_object()->instances)
+                        if (! print_object->has_mesh(sla_steps[istep]))
-                            aux_volume_state.emplace_back(state.step[istep].timestamp, model_instance->id());
+                            // Consider the DONE step without a valid mesh as invalid for the purpose
+                            // of mesh visualization.
+                            state.step[istep].state = PrintStateBase::INVALID;
+                        else
+    						for (const ModelInstance *model_instance : print_object->model_object()->instances)
+                                aux_volume_state.emplace_back(state.step[istep].timestamp, model_instance->id());
+                    }
 				}
 				sla_support_state.emplace_back(state);
             }
@@ -3911,7 +3920,7 @@ void GLCanvas3D::reload_scene(bool force)
                 const ModelObject *model_object = print_object->model_object();
                 // Find an index of the ModelObject
                 int object_idx;
-				if (! std::all_of(state.step.begin(), state.step.end(), [](const PrintStateBase::StateWithTimeStamp &state){ return state.state != PrintStateBase::DONE; }))
+				if (std::all_of(state.step.begin(), state.step.end(), [](const PrintStateBase::StateWithTimeStamp &state){ return state.state != PrintStateBase::DONE; }))
 					continue;
                 // There may be new SLA volumes added to the scene for this print_object.
                 // Find the object index of this print_object in the Model::objects list.
@@ -3942,7 +3951,7 @@ void GLCanvas3D::reload_scene(bool force)
                 }
                 for (size_t istep = 0; istep < sla_steps.size(); ++ istep)
 					if (! instances[istep].empty())
-						m_volumes.load_object_auxiliary(print_object, object_idx, instances[istep], sla_steps[istep], m_use_VBOs && m_initialized);
+						m_volumes.load_object_auxiliary(print_object, object_idx, instances[istep], sla_steps[istep], state.step[istep].timestamp, m_use_VBOs && m_initialized);
             }
         }
 

src/slic3r/GUI/GUI_ObjectList.cpp

@@ -1304,7 +1304,10 @@ void ObjectList::update_selections()
             const auto gl_vol = selection.get_volume(idx);
             if (selection.is_multiple_full_object())
                 sels.Add(m_objects_model->GetItemById(gl_vol->object_idx()));
-            else
+			else if (gl_vol->volume_idx() >= 0)
+                // Only add GLVolumes with non-negative volume_ids. GLVolumes with negative volume ids
+                // are not associated with ModelVolumes, but they are temporarily generated by the backend
+                // (for example, SLA supports or SLA pad).
                 sels.Add(m_objects_model->GetItemByVolumeId(gl_vol->object_idx(), gl_vol->volume_idx()));
         }
     }

src/slic3r/GUI/wxExtensions.hpp

@@ -200,7 +200,7 @@ DECLARE_VARIANT_OBJECT(PrusaDataViewBitmapText)
 // PrusaObjectDataViewModelNode: a node inside PrusaObjectDataViewModel
 // ----------------------------------------------------------------------------
 
-enum ItemType{
+enum ItemType {
     itUndef = 0,
     itObject = 1,
     itVolume = 2,