Unreal Engine 5 Lumen and Nanite are the revolution in the gaming industry but there is still 1 thing left to work on to make it perfect. I speak about shadows. To make an example if you place 10/20 point lights in a building and keep the shadow enable on all of them your frame rate will start to drop bellow 60fps for sure. The problem is that the shadows are rendered in the whole building without considering if the player actually can see the shadows or not.
I though about the following solution:
If the player can see the light volume he should be able to see also the shadow therefore the shadow renders, while if he cannot see the light volume he logically cannot even see the shadow therefore it should not render. In other words is a similar approach of how nanite works
Possible Extra Optimization: If there is a wall blocking the players view he cannot see the shadow anyway. So a good way will be to cast a low quality shadow first and check if at least one pixels is viewed by the player and if they is cast the high quality shadow if they aren’t to hide it.