Git Repository
https://github.com/ITR13/DotsCommunityChallenge-2024

Performance Strategy
NB: Please read controls on the GAME PAGE if you download this! It also goes more in-depth about the strategies, stats, and computer specs!

I've used 3 separate strategies that can be cycled through in the build. First one is inserting the data into NativeQuadTrees to quickly count how many entries are within an area. Second uses a hashmap to find neighbors, then generates multiple big arrays of counts. Third one works the same as the second, but has the HashMap store precalculated data instead of using ComponentLookup to get the data.

All strategies use pointer magic to add to multiple array entries at once, or to get a specific subarray. There's also a shader that takes in the raw data as a buffer, so that no time is needed to convert the data on the CPU.

The project page has more detailed info about specs, but it can run 4096x4096 cells at 100FPS, and 8192x8192 cells at 30FPS when not rendering.