[late]

The whole world has been mapped, and stored in the cloud. You can cache areas, if your internet is slow, or if you don't want to be in realtime mode. Realtime builds the world using current meteorlogical data. The modeling overall looks to be roughly a thousand times more involved. That includes weather. Clearly, if you want to run in 4K, you are going to need a seriously badass computer.

My interest in this is more for what it says about the future. I'd like to see something like this with VR and combat. That would get the old heart pumping.

https://www.youtube.com/watch?v=MOPIjzzH1G8