Model version check is disabled on Windows

[hannobraun]

When loading a model, the Fornjot app checks the Fornjot version that this model model uses, to prevent mystery errors due to incompatibilities. This check is currently disabled on Windows. There's a bug that prevents it from working there. See #1303 for context.

It would be great if we fixed that bug, and enabled the same version check on all platforms. Unfortunately, I don't have access to a Windows machine and lack Windows expertise. Labeling as https://github.com/hannobraun/Fornjot/labels/help%20wanted, as help would be especially appreciated!

[hannobraun]

I went over the version comparison code with a fine comb and found (and fixed!) a potential soundness hole. I don't know if that was actually the problem reported in #1303, but if it was, it's possible that the version check can be enabled on Windows without further changes.

[MartinKavik]

I've just pulled the latest main and deleted the condition for Windows and tried println! the versions and everything seems to work as expected now on Windows 10. Good job!

Btw is it possible to somehow filter debug! messages for a specific crate or a project? When I set RUST_LOG=DEBUG I see only a sea of wgpu_* and fj_viewer* messages.

[hannobraun]

I've just pulled the latest main and deleted the condition for Windows and tried println! the versions and everything seems to work as expected now on Windows 10. Good job!

Thank you! Such a subtle thing. I wasn't very optimistic that this would actually solve it!

Btw is it possible to somehow filter debug! messages for a specific crate or a project? When I set RUST_LOG=DEBUG I see only a sea of wgpu_* and fj_viewer* messages.

Yes: RUST_LOG=fj_host=debug cargo run

I think you can go even more fine-grained, by specifying this on the module level. And you can probably chain multiple directives using ,, but I might not remember the syntax correctly.