Hiding the sla support structures after undo/redo

src/libslic3r/Model.cpp

@@ -1134,7 +1134,7 @@ ModelObjectPtrs ModelObject::cut(size_t instance, coordf_t z, bool keep_upper, b
     if (keep_upper) {
         upper->set_model(nullptr);
         upper->sla_support_points.clear();
-        upper->sla_points_status = sla::PointsStatus::None;
+        upper->sla_points_status = sla::PointsStatus::NoPoints;
         upper->clear_volumes();
         upper->input_file = "";
     }
@@ -1142,7 +1142,7 @@ ModelObjectPtrs ModelObject::cut(size_t instance, coordf_t z, bool keep_upper, b
     if (keep_lower) {
         lower->set_model(nullptr);
         lower->sla_support_points.clear();
-        lower->sla_points_status = sla::PointsStatus::None;
+        lower->sla_points_status = sla::PointsStatus::NoPoints;
         lower->clear_volumes();
         lower->input_file = "";
     }

src/libslic3r/Model.hpp

@@ -199,7 +199,7 @@ public:
     std::vector<sla::SupportPoint>      sla_support_points;
     // To keep track of where the points came from (used for synchronization between
     // the SLA gizmo and the backend).
-    sla::PointsStatus sla_points_status = sla::PointsStatus::None;
+    sla::PointsStatus sla_points_status = sla::PointsStatus::NoPoints;
 
     /* This vector accumulates the total translation applied to the object by the
         center_around_origin() method. Callers might want to apply the same translation

src/libslic3r/SLA/SLACommon.hpp

@@ -18,7 +18,7 @@ namespace sla {
     
 // An enum to keep track of where the current points on the ModelObject came from.
 enum class PointsStatus {
-    None,           // No points were generated so far.
+    NoPoints,           // No points were generated so far.
     Generating,     // The autogeneration algorithm triggered, but not yet finished.
     AutoGenerated,  // Points were autogenerated (i.e. copied from the backend).
     UserModified    // User has done some edits.

src/libslic3r/SLAPrint.cpp

@@ -388,9 +388,9 @@ SLAPrint::ApplyStatus SLAPrint::apply(const Model &model, const DynamicPrintConf
                     if (it_print_object_status != print_object_status.end())
                         update_apply_status(it_print_object_status->print_object->invalidate_step(slaposSupportPoints));
 
-                    model_object.sla_points_status = model_object_new.sla_points_status;
                     model_object.sla_support_points = model_object_new.sla_support_points;
                 }
+                model_object.sla_points_status = model_object_new.sla_points_status;
 
                 // Copy the ModelObject name, input_file and instances. The instances will compared against PrintObject instances in the next step.
                 model_object.name       = model_object_new.name;

src/slic3r/GUI/GLCanvas3D.cpp

@@ -1905,7 +1905,10 @@ void GLCanvas3D::reload_scene(bool refresh_immediately, bool force_full_scene_re
         if (volume->volume_idx() < 0) {
 			auto it = std::lower_bound(aux_volume_state.begin(), aux_volume_state.end(), key, model_volume_state_lower);
             if (it != aux_volume_state.end() && it->geometry_id == key.geometry_id)
-                mvs = &(*it);
+                // This can be an SLA support structure that should not be rendered (in case someone used undo
+                // to revert to before it was generated). We only reuse the volume if that's not the case.
+                if (m_model->objects[volume->composite_id.object_id]->sla_points_status != sla::PointsStatus::NoPoints)
+                    mvs = &(*it);
         } else {
 			auto it = std::lower_bound(model_volume_state.begin(), model_volume_state.end(), key, model_volume_state_lower);
             if (it != model_volume_state.end() && it->geometry_id == key.geometry_id)
@@ -2018,8 +2021,14 @@ void GLCanvas3D::reload_scene(bool refresh_immediately, bool force_full_scene_re
                         ModelVolumeState key(state.step[istep].timestamp, instance.instance_id.id);
                         auto it = std::lower_bound(aux_volume_state.begin(), aux_volume_state.end(), key, model_volume_state_lower);
                         assert(it != aux_volume_state.end() && it->geometry_id == key.geometry_id);
-                        if (it->new_geometry())
+                        if (it->new_geometry()) {
-                            instances[istep].emplace_back(std::pair<size_t, size_t>(instance_idx, print_instance_idx));
+                            // This can be an SLA support structure that should not be rendered (in case someone used undo
+                            // to revert to before it was generated). If that's the case, we should not generate anything.
+                            if (model_object->sla_points_status != sla::PointsStatus::NoPoints)
+                                instances[istep].emplace_back(std::pair<size_t, size_t>(instance_idx, print_instance_idx));
+                            else
+                                shift_zs[object_idx] = 0.;
+                        }
 						else {
 							// Recycling an old GLVolume. Update the Object/Instance indices into the current Model.
 							m_volumes.volumes[it->volume_idx]->composite_id = GLVolume::CompositeID(object_idx, m_volumes.volumes[it->volume_idx]->volume_idx(), instance_idx);

src/slic3r/GUI/Gizmos/GLGizmoSlaSupports.cpp

@@ -84,7 +84,7 @@ void GLGizmoSlaSupports::set_sla_support_data(ModelObject* model_object, const S
 
         if (m_editing_mode_cache.empty()
          && m_model_object->sla_points_status != sla::PointsStatus::UserModified
-         && m_model_object->sla_points_status != sla::PointsStatus::None)
+         && m_model_object->sla_points_status != sla::PointsStatus::NoPoints)
             get_data_from_backend();
 
         if (m_state == On) {
@@ -961,7 +961,7 @@ RENDER_AGAIN:
         m_imgui->disabled_end();
 
         // m_imgui->text("");
-        // m_imgui->text(m_model_object->sla_points_status == sla::PointsStatus::None ? _(L("No points  (will be autogenerated)")) :
+        // m_imgui->text(m_model_object->sla_points_status == sla::PointsStatus::NoPoints ? _(L("No points  (will be autogenerated)")) :
         //              (m_model_object->sla_points_status == sla::PointsStatus::AutoGenerated ? _(L("Autogenerated points (no modifications)")) :
         //              (m_model_object->sla_points_status == sla::PointsStatus::UserModified ? _(L("User-modified points")) :
         //              (m_model_object->sla_points_status == sla::PointsStatus::Generating ? _(L("Generation in progress...")) : "UNKNOWN STATUS"))));
@@ -1190,8 +1190,8 @@ void GLGizmoSlaSupports::editing_mode_discard_changes()
     else
         editing_mode_reload_cache();*/
 
+    select_point(NoPoints);
     m_editing_mode_cache = m_old_cache;
-
     m_editing_mode = false;
     m_unsaved_changes = false;
 }