Remove Luxcoreui nativefiledialog dependency

[howetuft]

Remove nativefiledialog dependency from luxcoreui

Proposal overview

This is a proposal to replace nativefiledialog, in luxcoreui, by a lighter file dialog provider.

Rationale

luxcoreui relies on ImGui framework for its graphical interface. However, ImGui does not provide any file dialog (well-known drawback...), so a dedicated dependency, called nativefiledialog, was introduced in luxcoreui to remedy.

Problem is nativefiledialog requires gtk3 as a dependency, with several consequences:

• in Conan, gtk3 is a "system" dependency, meaning that Conan (logically) does not provide any source recipe nor precompiled version, but relies on system packages. It can lead to ABI incompatibility and crashes, when compiling on a platform and running on another.
• if we try to bundle required gtk3 binaries with luxcoreui, it leads to a bunch of embedded shared libs, some of them having very little relationship with luxcoreui (like sound libs etc.). Moreover, Cmake standard dependency installer mainly focuses on direct deps, which leaves the problem open for indirect deps.
• it prevents luxcoreui from running in a containerized environment (snap etc.), as gtk3 libraries access are restricted in such an env.

Candidates are:
imgui-filebrowser
imguiFileDialog, from ospray Studio

[CodeFHD]

No objections to replacing the dependency.

With respect to your already made proposal to replace luxcoreui with a python-based alternative, I would suggest to pick whatever is easiest to implement, if it makes any difference, and without too much concern for support periods.

We should understand and chart the current features of luxcoreui (might be documented in the wiki), then draft a concept for a new python GUI. With that, we can define a timeline when it should be available.

[howetuft]

You're right! imgui-filebrowser seems better documented, so I'm thinking of selecting this candidate.

[howetuft]

I eventually opted for imguiFileDialog, of which I finally found the website and the doc (https://github.com/aiekick/ImGuiFileDialog/tree/master), and which seems to be the de facto standard.

[CodeFHD]

@howetuft Reviewing if this Discussion can be closed or should remain open.

I don't see any references to nativefiledialog any more, except in the readme, and LuxCoreUI generally works, so unless you have specific actions remaining we could close this?

[howetuft]

Yes we can close!