As a precision I already noticed threads about this but didn't find a way to achieve exactly what I need.
Basicaly I have a board of objects that I need remaining always on top of everything but also attached to the camera.
I first tried to add the group to the camera and it stayed as wished always in the viewport. But in this configuration the group of objects still be a part of the scene so while zooming to regular objects in the "editor" the board goes into/among these objects of the scene.
My second trial was based on this thread and work wonderfully in order to get all of the board objects rendered above everything. But on such a configuration when rotating around the axis (with orbit control) both scenes rotates. So I tried to update the foreground scene with coordinates of the camera but the update was not immediate and this scene is flickering (I suppose that while rotating the update function is not called immediately).
My best wish would have been to "attach" the foreground scene to the camera so that it would stay on top and sticked on the screen/viewport but I don't even know if it is possible and how to do that (as only groups of objects seem to be capable to be attached to the camera).
I am really stuck on that point. Thanks you for any help!
