[ovao]

The question would be “by what dimension of interesting”?

Quake 3’s source is pretty interesting from the perspective of id just transitioning from C to C++, and famously has an implementation of fast inverse square root. It’s also a pretty clean codebase overall with a reasonably modern engine architecture.

[bhelyer]

Quake 3 was still completely C, IIRC. You might be thinking of Doom 3?

[synergy20]

the rerelease mentioned here rename .c to .cpp globally but the code base is still c, why is that? I thought it was rewritten in c++.