Allow spawning npc via iuse action

[ZhilkinSerg]

Summary

SUMMARY: Infrastructure "Allow spawning npc via iuse action"

Purpose of change

Allow spawning npc via iuse action (somebody on Discord wanted to use it in a mod).

Describe the solution

Added new iuse action for spawning npc.

Testing

Add following code to any item and activate it in game to spawn npc:

    "use_action": {
      "type": "place_npc",
      "npc_class_id": "true_foodperson",
      "summon_msg": "You summon a food hero!",
      "place_randomly": true,
      "moves": 50
    },

[Fris0uman]

The Foodsignal is lit!

[yowshi]

this would be so awesome to have.

[BevapDin]

This needs an item that actually invokes it. Currently it's just dead code.

[yowshi]

This needs an item that actually invokes it. Currently it's just dead code.

well, he has an example of something which invokes, and it came out of a question of me asking if there was a way to spawn NPC's outside of debug menu.

EDIT: Because i have plans for an item which does exactly that.

[BevapDin]

This should check !g->m.passable. Currently this function may find a point that is actually impassable. Try this out inside solid rock, with only one free spot for the player character to stand on and one other free spot, with a target_range above 0. It will almost always find a random point that is actually impassable, but there is a suitable spot nearby.

Later this will be reported as "There is no square to spawn npc in!". (It actually wont, as calling value on an empty cata::optional will already fail.)

[BevapDin]

What about tiles that have only air (no floor)? What about tiles that another creature (npc, monster, player) in it?

[ZhilkinSerg]

I will update it in a follow-up PR.

[BevapDin]

This should be below, outside of the if( place_randomly ) block, so it considers the result of random_point as well.