Where are the codes for passive bionics effects

I’m trying to find effects for air filtration system. I searched for “bio_purifier”, “air filtration system”, neither came up with anything. and src/bionics.cpp only has activated bionics effects.

Where are the codes for passive bionics?

They are tied in wherever they would have an effect, similar to how mutations are. So for example the air purifier code probably is present anywhere that deals with breathing.

The easiest way I find to track it down is just to do a mass file search (either through snazzy stuff or through something as simple as opening up all of the various source files in N++ and then doing a “find in all files”) for the id (i.e. bio_purifier).

In this particular case it’s in player.cpp, under get_env_resist.