Comments URL: https://news.ycombinator.com/item?id=48369594

Points: 3

# Comments: 0

This way if one input packet gets lost, the very next one getting through will have all the inputs for the last 1-2 seconds, and this greatly improves how well your game will play under packet loss.

When you do this, you can even do an encoding from left -> right for all inputs, and actually, sort of delta encode inputs within the packet! Inputs don't change that much, so you can even get smart with the encoding and optimize it down to basically nothing.

He does this by only rolling back and re-simulating only a subset of the world, greatly reducing the amount of CPU required. It's cool that he's approaching this from the point of view of adding support for it in the physics engine itself, vs. making it something that the game has to do themselves.

Delta compression is an unrelated technique which reduce the amount of bandwidth sent from server to client, by sending only the differences between the snapshot at baseline frame n and the current snapshot frame m on the server.

Just want to clear this up for anybody trying to follow along. Bringing in delta compression is an unrelated thing (but somewhat similar conceptually). It might confuse people to talk about these things at the same time, if they're really just trying to understand what the author is doing in the article.

cheers

- Glenn

Comments URL: https://news.ycombinator.com/item?id=47933585

Points: 3

# Comments: 1