And then when every time the user interacts with the system you would have to trash the GPU queue and recompute everything. If you could compute everything befo

And then when every time the user interacts with the system you would have to trash the GPU queue and recompute everything. If you could compute everything before hand, it would be far simpler just encode the entire scene as a video. For example, consider a game server that must handle inputs from multiple clients. It can't just compute everything and queue it off to the network because a user input may change the entire game world. A "computation" loop provides a consistent model of which all the game interaction happens.