Need a GDNative Library for IOPiper

[andrew-wilkes]

It's better to have a code library such as a .dll file for the interface to a Chess engine and connect to it with GDNative.

Golang bindings are available but the available code is no longer supported (so it should be regarded as deprecated) , yet there is ongoing support for other languages such as D and Nim.

Action: Code a DLL using D lang - my personal preference.

Godot game engine language bindings

Related Docs: Supported Languages

Note: I personally don't want to write C or C++ code since I want to use modern alternatives. But I am happy to have a range of solutions in any language submitted here.

[andrew-wilkes]

So, now I regained interest in this feature. My idea is to code it in Rust via a GDExtension since Rust is supported for GDExtensions https://github.com/godot-rust/gdext

A quick search for Chess Engines implemented in Rust led me here: https://github.com/pleco-rs/Pleco/tree/main/pleco

So there are various ideas to explore:

• Have a GDExtension that spawns a chess engine process from an executable file on the PC and communicates with it via STDIO which is flexible to support any Chess Engine
• Integrate a chess engine into a GDExtension which is the most direct way, but could have licensing issues, and is less flexible
• Develop various tools or extensions that make it easy for developers to play with and come up with their own solutions

At the moment, I am still learning Rust before I can do much to implement these ideas.

[andrew-wilkes]

So I have a plan:

Implement a GDExtension using Rust that uses the process(delta) function to poll a message that needs to be sent to the Chess Engine, then it waits for a few ms where error signals may be sent, then it sits on a blocked IO read until a line of text is received, and then it outputs this text, and the state goes back to polling the send message text value.

I could not find any way to implement non-blocking IO. The expectation here is that the Chess Engine will always output a response to an input. We can have a delay before we start getting an expected response from stdout. If the Chess Engine does not respond, then our App. will crash (forever locked/unresponsive).