As title says, lights seem to work just fine without adding them to the scene.

You create a light picker, fill it with your lights and set up the materials you want lighted so they use that light picker.

In that case, what benefits does it bring to add lights the scene ? And is there any drawback such as a particular performance costs that don’t occur when they are active but not added ?

Thanks

Partly answering myself again as it could be useful for someone some day. If you can complete this answer I’m all ears.

- Adding a light to the scene enables casting shadows of objects. If you don’t add the light you can still use shadow methods and shadow mappers but the result will be radically different, it seems.