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Population Based Garrison Requirements

In vanilla, garrison requirement depends solely on the state's resistance level and the occupier's occupation law. This leads to the ridiculous situation where a Pacific island with a few thousand residents requires the same garrison size as a Chinese state with 53 million people.

Every state now has a modifier to garrison requirement based on its population (calculated on_startup and yearly). A state with a population of 2.5 million-- seemingly the average in Western Europe-- will have the base garrison size requirement. A state with 5 million population will have double the requirement, while a state with 1.25 million will halve the requirement, etc.
Note that Hoi4 has only 1 garrison requirement modifier so the population impact is additive with garrison laws/anything else that modifies garrison requirements. A state with fewer than ~625,000 people and 0% resistance won't need any garrison on civilian occupation, since the -75% modifier from population size and -25% modifier from civilian occupation add up to -100%.

PBGR does not allow achievements. However, it should be compatible with EVERY mod that does not overwrite common/dynamic_modifiers or common/on_actions. I have not tested with any other mods, so try them out for yourself.

The code is very simple-- 26 lines in 2 files-- and the state population where PBGR equals vanilla can be changed on the first line of common/on_actions/pop_based_garrison_actions.txt. Feel free to include PBGR's code in your own mod or make variations with different requirements, but please credit & link to me.