   Scene graphs and entity systems
  Hi,I got a scene graph running in my engine and now it's time for some interactive stuff. Since a scene graph is supposed to handle scene rendering I don't want to treat its nodes as game entities (like handling collision in the scene graph). I wonder what's a nice/best approach to make the idea of scene nodes and entities work side by side without redundancy etc.?Any ideas, papers or tutorials?Thank you!   
  Well one way would be the normal entity approach.Having a entity baseclass where all ur entities derivere from and keeping them in a list.All entities should be able to register for input and update calls.Then the entities keep a pointer to the scenenode/s they own and on destruction they also release the scenenodes. Same is for ur physics stuff. All is keeped by the entities so u won't have to search through the list of nodes and physic objects and most important u will need a callbacksystem for ur entities to communicate. So for example the player entity registers for a callback which is called "HealPlayer" and when u want to heal the player/s u won't have to search for them.   ;  If you use an entity/component system, then a scene-graph node can be a type of component, which can then be part of a composite entity.   