--hotcodereloading:on How to get it working?

[pragmagic]

--hotcodereloading:on How to get it working?

[geekrelief]

I've made some progress on this, but I'm a bit stuck. Basically, I have a loader module that is imported by stub.nim. The Loader spawns a thread that monitors the modification time on a helper dll. If the modification time is newer it unloads the old dll and loads the new dll. After loading the helper dll, I call its godot_gdnative_init and godot_nativescript_init to initialize things.

I've made the necessary modifications to the bindings and stub to get print working (I get output in the editor console), but when I try loading a module with a class created from gdobj (e.g. mainpanel.nim) in the helper an exception occurs when calling godot_nativescript_init.

I can't really think of another way to debug this unless I modify the generated c files from the godot-nim bindings to bisect the issue. Any clue what might be going on? Is there an easier way to debug this?

[geekrelief]

I got hot reloading working by using gdns as resources. It requires a modification to the Godot engine which I reference here: godotengine/godot#42449 (comment) The basic idea is that we need a Watcher node monitoring a Component. The component has two dlls: one is the safe dll and the other the hot dll. The hot dll is referenced in a gdns file as a sub resource so we're free to compile to the safe dll. In my scene the Watcher node checks the modification times of the Component's dlls and if the safe is newer than hot, destroys references to the Component. This triggers NativeScript for the Component to destruct engine side. The engine modification ensures that in NativeScriptLanguage::unregister_script, if no script is referencing the hot dll, the hot dll is terminated which releases the file lock on it. In the Watcher we can then write over the hot dll. And then we can go further by saving data before the reload, and restoring it after.

[geekrelief]

@endragor If you're interested I have a working framework for hot dll reloading. https://github.com/geekrelief/gdnim Not sure how feasible this is to integrate with godot-nim / godot-nim-stub because it relies on an engine modification, but I figured I'd share in case you're interested. So far I've only written some small components with it, but I don't see why it wouldn't scale.