generational-arena VS goprotobuf

In my experience it is often easier to use indexes instead of copying Rc's. If you want to mutate the graph, then look in to slab and generational-arena

Regarding ECS: yes, but in a deflationary sense. The game has entities, stored in something very similar to GenerationalArena, and it has "systems", which are just functions that operate on these entities. The components themselves are just fields of the Entity megastruct. Having an ECS in the narrow sense doesn't really make a lot of sense for this game, because a lot of its rules are dependent on each other, and there's very little chance to extract parallelism. Also, even the current largest levels have less than 10k entities, so simulation performance is not a bottleneck yet.

If you cannot inplace construct the slice-dst on heap and your slice is too large to be copied, then I think there are two solutions: - Using Box>, this adds another level of indirection but avoids the copying - Use an arena like slotmap, slab, generational_arena or concurrent_arena to store the Box<[u8]>. It still needs heap allocation, but it allocates in chunks, thus less fragmentation and performs better.

I think this is less of a good fit though: the word "arena" doesn't imply iteration is possible to me. I think arenas also conventionally will reuse previously-released handles (unless you implement akin to a generational arena), so the term might be a bit misleading in that regard.

Might wanna check out https://github.com/fitzgen/generational-arena / https://github.com/ArnaudValensi/vec-tree/blob/master/tests/tests.rs.

This is far from the only arena allocator written in Rust.

From the same author, a zero-unsafe arena allocator: https://github.com/fitzgen/generational-arena

There are many, many arena implementations available with varying characteristics. It's disingenuous to act like Rust requires the author of an arena library to write "unsafe" everywhere.

If someone wants to adapt it to create computergames, then it would probably be useful to find a way to introduce generational generational indexes

Now let’s take a look at the source code of the protoc-gen-go plugin:

Wait, you say, in Go you can embed a struct with default method implementations to "inherit" them in your composed struct... sure, except any methods called by those methods are early-bound in the original struct, completely ignoring your wrapper, so the best you can do is "not implemented" rather than actually implement something. It is at least a way to prevent semver-major breakage, which the gRPC generator uses, but that's about as far as it gets you.

The classic answer is protobufs. You can serialize out to binary format.

Seems like go is pretty middle of the road. I can only guess as to why but it probably has to do with heavy usage of pointers and reflection which are much slower than other implementations. Gogo/protobuf (RIP) solved this performance with code generation, but the the official go protobuf implementation has essentially eschewed it. I do wonder how the benchmark would look using the new vitess proto library for Go (which has many of the benefits of gogo but with active development and an API built on top of the Google one)

Maybe I'm missing something, but my read of [golang/protobuf#364](https://github.com/golang/protobuf/issues/364) was that the re-organization in protobuf-go v2 was allow for optimizations like gogoprotobuf to be developed without requiring a complete fork. I totally understand that the authors of gogoprotobuf do not have the time to re-architect their library to use these hooks, but best I can figure this generator does not use these hooks either. Instead it defines additional member functions, and wrappers that look for those specialized functions and fallback to the generic ones if not found.

I am thinking about stuff like the [ProtoMethods](https://pkg.go.dev/google.golang.org/[email protected]/reflec...) API.

I wonder why not? Did the authors of the vtprotobuf extension not want to bite off that much work? Is the new API not sufficient to do what they want (thus failing some of the goals expressed in golang/protobuf#364?

In this case try approach with line by line generation. Very much like what protoc-gen-go does for Go code: https://github.com/golang/protobuf/blob/ae97035608a719c7a1c1c41bed0ae0744bdb0c6f/protoc-gen-go/grpc/grpc.go#L142, need to implement this kind of generator yourself.

Something like this: https://github.com/golang/protobuf/blob/master/internal/gengogrpc/grpc.go