separate display properties from properties

src/Vtk/uLibVtkInterface.h

@@ -284,6 +284,21 @@ public:
   void save_override(const boost::archive::class_name_type &t) {}
   void save_override(const boost::archive::tracking_type &t) {}
 
+  // Called by Property<T>::serialize() and EnumProperty::serialize() to
+  // directly register an existing property object as a display property.
+  void register_property(uLib::PropertyBase &p) {
+    if (m_Puppet) {
+      m_Puppet->RegisterDisplayProperty(&p);
+      Vtk::Puppet *puppet = m_Puppet;
+      uLib::Object::connect(&p, &uLib::PropertyBase::Updated,
+                            [puppet]() { puppet->Update(); });
+    }
+  }
+
+  void register_enum_property(uLib::EnumProperty &p) {
+    register_property(p);
+  }
+
 private:
   Vtk::Puppet *m_Puppet;
   std::vector<std::string> m_GroupStack;