Rustified Civ 4 DLL

Instructions

• Follow the guide to set up compiling the DLL on Linux/WINE
• Change any settings in CvGameCoreDLL/compile_settings.sh
• Change any settings in config.ron
• Run cargo xtask [build/run]

Limitations

• This is still super early stages, so at the moment basically nothing is implemented or works
• Because Civ 4 uses such an old compiler (from ~2003), we can't compile with a modern MSVC toolchain, like the one Rust wants to use. This means we build the Rust library as a #[no_std] library (std wants to link to the MSVC runtime, then we have two versions of it linked that conflict!)
• Because the compiler is so old, I don't expect bindgen would really work too well, so we might have to write the extern "C" blocks by hand - but I've not investigated this yet
• Also because of this, I've had to write a simple compatibility layer for the cstdint types - I'm not sure how correct this is, but am hoping it's close enough!
• The compile.sh/compile_settings.sh scripts should probably be re-written in Rust or something? At the moment this'll only work on Linux!
• cargo xtask run will only work with a Steam install of Civ 4 at the moment
• There's probably a huge amount more other problems waiting to be discovered!

Tips

If you want to run Civ4 windowed on a high-res display, you can use gamescope - I've been running it with my Steam command set to:

INTEL_DEBUG=norbc VK_ICD_FILENAMES=/usr/share/vulkan/icd.d/intel_icd.i686.json:/usr/share/vulkan/icd.d/intel_icd.x86_64.json gamescope -w 1440 -h 960 -W 2880 -H 1920 -n -r 60 %command%

Symbols

There's a simple symbol dumper you can run with cargo xtask dump [ClassName] (eg cargo xtask dump CvGame) which'll output a dump.rs file containing (unsafe) rust bindings to all of the functions associated with a class.

These generated bindings are only a starting point, and will need to be fixed-up to be able to work properly - and they don't have any safe wrappers generated with them!

To get a raw list of the (mostly mangled) symbols - you can run this:

objdump -x 'CvGameCoreDLL/Output/CvGameCoreDLL.dll' > dump.txt

Then "just" ctrl+f to get the actual function name you're looking for.