Attempting to create a port for Unity

[MasterSix997]

Hello.
In my autonomous tests, I found that this library is a good alternative to ImGui.Net, but I had a failed attempt to create a port of it for Unity, it seems that it uses some newer C# features, which have not yet arrived in Unity. Is there any way to downgrade or generate older code with the generator used?

[JunaMeinhold]

Hi,
why do you need to port it, like it supports netstandard2.1/2.0 that should be enough to get it running in Unity. Or do i miss something?

[sakitume]

I have attempted something similar as well. I encountered a few issues along the way and decided to set it aside and instead continue using ImGui.NET but modifying that as needed. It would have been great though if I could have instead gotten Hexa.NET.ImGui to work.

My experiments with Hexa.NET.ImGui and Unity were performed on an M1 macBook and using Visual Studio Code. I believe that two components were needed.

• HexaGen.Runtime
• Hexa.NET.ImGui

The DLLs for these need to be targeted for netstandard2.1/2.0 (I chose 2.1) as mentioned by @JunaMeinhold

I think most of the issues I encountered were with HexGen.Runtime. The NativeLibraryLoader.Load() method needed adjustment as it tries to use libdl.so which in mycase won't resolve. Instead We need to use [DllImport("dl")] for newer macOS versions (I guess).

Another issue I came across was that HexaGen.Runtime uses several well known (predefined) paths (see GetNativeAssemblyPath()) which I don't think are compatible with how Unity works with what it calls "native plugins" (these dynamically linked libraries) and therefore has problems trying to load the cimgui shared library. I recall trying a few things before figuring that out. I think I found a workaround so that it could then resolve cimgui but at that point I suffered fatal crashes of the Unity Editor and did not want to spend additional time trying to figure out what was crashing.

I suspect this can still be made to work. But for my needs I knew I could instead update ImGui.NET and modify it for my needs. Some day I hope to revisit Hexa.NET.ImGui. Perhaps if this issue gains traction I will be able to do that, or possibly even help contribute with this effort.

[JunaMeinhold]

I will look into it after i recover from my cold and other important irl stuff.

[MasterSix997]

thanks for the help, I hadn't realized that Hexa.NET.ImGui supported netstandard 😳

I don't know much about macOS, and my testing was on Windows, and I didn't have much trouble "porting" the package I had already created using ImGui.Net, just one issue where Unity couldn't load cimgui. So I manually compiled cimgui for Win-64 and it worked.

There are still some issues with the way the package was created (to use ImGui.NET), so it will require a bit more work than just changing the namespaces, and I still think it would be a good idea to move some of the code to use direct bindings instead of overloads.

Here's the pull request if you want to see it: MasterSix997/UBImGui#4

[JunaMeinhold]

You can download the pre-build libs from Github actions (in this repo)

https://github.com/HexaEngine/Hexa.NET.ImGui/actions/workflows/cimgui-cmake.yml
Or from here (if the artifacts already expired)
https://github.com/HexaEngine/Hexa.NET.ImGui/tree/master/native

And what do you mean with "direct bindings" like my wrapper allows you access the raw C functions?
The overloads are just for convince.

[MasterSix997]

Yes, I downloaded the libraries already built, but for some reason Unity can't recognize them, even with the correct settings, it only worked when I built them manually.

And what I meant by direct bindings is that since I wrote the code based on ImGui.Net, I used the overloads of the native functions, for greater ease, but maybe it's better to use "direct bindings" to avoid the GC.

[MasterSix997]

One more thing, I don't know if it's just on my computer, but it seems like the generated code is a bit... massive?
My Rider IDE and vscode get extremely slow when the autocomplete opens just by typing "ImGui".
I've never had this happen before, and it's only with this class (ImGui) ¯(°_o)/¯

[JunaMeinhold]

Did you build cimgui in release or debug profile? (because the pre-build ones are build in release profile)

About the native overloads, they are present:

Yeah i know the generation is massive like it uses all my ram (and i have 32GB)

[JunaMeinhold]

You could also join my discord if you want, i usually reply faster there compared to GitHub issues. (see Readme for link)