Location of the "max shadow creatures spawned" code

[Sacco]

I've been searching for a awhile but i haven't found any line of code referring to the max number of shadow creatures spawned at max for a single player when crazy.

I've found SANITYMONSTERS_INDUCED_MAXPOP = 5 but it doesn't work if i change it through a mod, and i also recall that the max shadow creatures spawned is 2/3.