Add exclusiveUnite method
Use exclusive unit
Update 3DWIddget to limit OpenGL call
Add the possibility to use GLC_ViewHandler::updateGL method in
synchronous mode in order to simplify OpenGL feedback
Add the possibility to knonw if a 3DWidget is visible.
Add the possibility to know if a 3DWidget is visible
Add the possibility to set attached world after class construction
Update selection behavior (Return a GLC_Selection and the unprojected
point)
Add the possibility to know if a collection contains visible instance
Add the possibility to update selection from a selection event
Update selection behavior.