Npc attack #47562

KorGgenT · 2021-02-17T02:14:36Z

Summary

Features "Implement new logic for NPCs to choose their attacks"

Purpose of change

We've been wanting to improve the npc ai, but afaik noone wanted to carry that torch. so here i am! :D

Describe the solution

requires #47207 as it has commits from this PR to break it up a bit.

implement a new npc_attack class with child classes for the different styles of attacks. in this PR, that is melee, gun, throw, and activate_item. throw has a fairly basic implementation because i needed the npc to understand that grenades needed to be thrown, and the activate item attack is for feature parity with npcs using grenades. Unfortunately, it looks pretty involved to properly estimate when it's a good idea to throw a grenade, so the likelyhood of an npc throwing a grenade is "not unless i'm surrounded, can't run, and there's no other option". grenades will have to be their own PR.

add a new method in npc to evaluate all of its possible attack options and save the npc_attack and its data (called npc_attack_effectiveness) into the ai_cache. then just activate it via npc_attack::use.

Describe alternatives you've considered

Watching npcs throw their pants at zombies

Testing

i'm writing some tests, and additionally i have run some live tests where i equipped an npc with a specific item and watched what they did with it. i can confirm that they throw items, use attack spells, fire guns, and use melee weapons. they also use grenades if their surrounded and are naked! (if they don't choose to run away first)
I'm drafting this to get it out in the open for some code review, though i'm pretty aware that i'm not done writing up the tests.

Additional context

follow ups should be, in no particular order:

spell
bionics
mutations
grenades
some other item activations perhaps?

src/npc_attack.h

src/npcmove.cpp

actual-nh · 2021-02-17T03:13:26Z

I have been contemplating how to have a monster not use a particular option unless pressed - something more than "only do it every X turns". Possibly dependent on Anger above starting and Morale below starting?

BrettDong · 2021-02-17T05:59:10Z

Need to add virtual destructor to other classes as well.

KorGgenT · 2021-02-17T06:04:33Z

i really don't understand why exactly

KorGgenT · 2021-02-17T06:05:43Z

blergh, i've run both the astyle and json linting tools from VS but they didn't do it (for the json.. turns out i ran astyle on the wrong branch)

src/npc_attack.cpp

src/npc_attack.h

mlangsdorf

Overall, it looks good and I didn't see any structural problems in the code. @Aivean should probably look over it for performance improvements but I'll leave that to his expertise.

Submission wise, I think a bunch of this can be broken into separate PRs for easier review. There's a lot of generic infrastructure work before you get into actually implementing the changes to the NPC AI. Normally, I wouldn't make such an issue about it, but this is such a large PR that it usefully could be trimmed.

src/character.cpp

src/item.cpp

src/magic.cpp

src/npc_attack.cpp

KorGgenT · 2021-03-13T12:18:30Z

please excuse the individual commits for now, i'm trying to do miniscule changes to fix up the error messages in order to squash them into the correct commit later.

kevingranade · 2021-07-02T15:24:32Z

This pull request has been mentioned on Cataclysm: Dark Days Ahead. There might be relevant details there:

https://discourse.cataclysmdda.org/t/magiclysm-a-total-fantasy-overhaul/20612/512

This implements a class that owns all of the logic for an npc evaluating the best weapon to use in the moment.

This reverts commit 8d721b4.

KorGgenT added <Enhancement / Feature> New features, or enhancements on existing NPC / Factions NPCs, AI, Speech, Factions, Ownership [C++] Changes (can be) made in C++. Previously named `Code` 0.F Feature Freeze labels Feb 17, 2021

KorGgenT requested a review from mlangsdorf February 17, 2021 02:14