FEAT: ship with built-in FreeImage

[FirefoxMetzger]

This PR adds plumbing to download, compile, and package the freeimage binary and make it part of the distributed wheel.

[almarklein]

I'm trying to run this on my Mac. Using poetry build to build now. Can it also be build without poetry btw?

edit: ah, can also do setup.py install

Not there yet, but I'm making progress. This seems like a good resource: https://www.ultraengine.com/community/topic/59665-freeimage-build-errors/

When I know what to change, can I just change the FreeImage source or do you want it to be patched at runtime somehow?

[almarklein]

Now stuck at

clang: error: invalid argument '-bundle' not allowed with '-dynamiclib'

[FirefoxMetzger]

I'm trying to run this on my Mac.

Thanks @almarklein 🎉

Can it also be build without poetry btw? edit: ah, can also do setup.py install

Yes and no. Under the hood poetry build generates a setup.py and calls distutils when building C extensions. If you have a setup.py in your repo, then that is because the process has crashed during building and didn't remove the autogenerated file :D

That said, it's perfectly fine to use it and, once things work, I can "port" it to poetry build.

An alternative could be to use the build system that ships with FreeImage (makefiles) and then just copy the binary into the target location. If that works directly without making modifications then I'd prefer that solution.

When I know what to change, can I just change the FreeImage source or do you want it to be patched at runtime somehow?

So far, I've downloaded the FreeImage source directly from Sourceforge, because I thought this is the easiest way to say "look, this is just vanilla FreeImage". However, if we do need to modify the source then I think it will be much easier for us to vendor the code.

Which option do you think is less work for us?

[almarklein]

Under the hood poetry build generates a setup.py

Right, I found out after I posted :)

Which option do you think is less work for us?

I suppose it'd be easier if it stays visible what diffs we're applying, so that in case of an update they still work and/or can be updated ...