Question Most straightforward way to create a lookup table that can be accessed in Burst?

Suppose I want to create a lookup table game mapping keys of some blittable type to values of some blittable type. I'd guess this is a pretty common use case.

Prior to Entities 1.0 I would have just used a NativeHashMap, stored it on some managed (singleton) component, and then retrieved the NativeHashMap prior to executing an Entities.ForEach call. From my understanding the Entities.ForEach call would still be burst-compiled and it could read from the NativeHashMap.

However, since Entities.ForEach seems to not be recommended anymore, I am looking for an equivalent way to do this using idiomatic ForEach and/or ISystem. It seems to me that ISystem requires the entire OnUpdate call to be burst-compiled or not, which means I can't access any managed components. And from my understanding, idiomatic ForEach isn't bursted unless run within a bursted ISystem.

Does anyone know of a solution? I'd like to keep using NativeHashMaps, if possible, just for the dictionary-like syntax. I imagine there is a way to do this with blob assets but there currently is no official BlobHashMap anyway.

 

You can still use unmanaged singletons to store collections if you want. Same usage pattern as using a managed singleton, just use a struct instead of a class. I’ve been doing this in 1.0.0-pre.15 with no problems using NativeParallelHashMap / NativeMultiHashMap.

 

Oh, oops. Somehow I had gotten the impression that native collections couldn't be in unmanaged components. I guess that is pretty straightforward, then.