ludic/packages/ludic.npc

ludic.npc

The other people in a place: each with a routine by the hour rather than an intelligence - where they start, where they go and what they do there, when they walk out - walking between spots and round whatever is in the way, never into the water, turning to face a player who comes near, and saying one line at a time from a table of lines. Uses ludic.base and nothing else.

import "ludic.npc"

The package owns the people's state, the census, the walk, the acts, the lines, its own dice and a guest's copy of a host's people. It never draws: the port says a person was born (make an actor, key it by the person's slot, or id across machines) and gone, and the game reads x, y, z, yaw, act, stalk and phase (2.6 a metre walked) every frame to pose it. Clips are the game's too (NpcAct.clip is a hint: "walk", "idle", or "" for a pose of its own).

Four tables the game fills

• NpcKinds - a kind of person: weight in the census draw (night: the only kinds drawn after dark), whether it stays the night, leave_lo .. leave_hi (the hour it walks out), notice (m it turns to face a player), start (where a new one goes: call npc_start_near(p, x, z, r0, r1)), plan (the first word on what next; true: decided) and steps, its routine.
• NpcStep (inside a kind) - in the hours from .. to (round midnight when from > to), weight of the draw, go to spot (near .. far m, n the spot's own number) and do act for lo .. hi seconds. A step whose spot cannot be found gives way to the next one in the table.
• NpcSpots - where a step goes; find(p, step) sends the person (npc_go / npc_do, or npc_step_go) or says it cannot. The package's own: here, home, near_home, near_here, shore_home, shore_here (facing the water) and wander; a game adds its own (a sign, an animal).
• NpcActs - what somebody does; the package's walk (NPCA_WALK) and idle come first. turns (false: keeps its eyes on its work), clip, and tick(p, dt) (the game's while it lasts; true: decided).
• NpcNames (name, body) and NpcLines - see below.

A kind's .lres may name functions (start: fn my_start), and a step list is [{ ... }, ...].

The rules it keeps

1. A routine, not a mind. A person plans on arriving and when its act runs out: the kind's plan, then a weighted draw among its steps for this hour, then standing a while.
2. Nobody walks into the lake or up a scramble: a step into water (0.4 m) or up more than 1.4x the step is refused; eight steps round are tried, and a target that gets no closer for twenty seconds is given up (three times: a few steps anywhere walkable).
3. Nobody stops where the place says not to (NpcWorld.allowed: a player's camp). They may walk through; an act begun there walks out first.
4. They face whoever came over to talk, within the kind's notice - unless creeping or at an act that does not turns - and go back to their errand when the player walks off. A player coming within notice is a Greeted fact, once, until they have gone half as far again.
5. The census is counted, not tallied, on the half hour: up to NpcWorld.want() (and never past npc_config's cap), plus NpcWorld.extra() whatever the crowd.
6. They leave only out of every player's sight: after their hour at 120 m, at night (by 22:00, except those who stay) at 70 m, and a crowd over what is wanted at 150 m - never while out for something (goal >= 0).
7. No name twice: not another person's, not one the place keeps (NpcWorld.taken), not one that left lately.
8. Posts (npc_place: a vendor) never walk, are never counted and never leave; they turn to a player within notice and back to their stance.

Lines as data

hush { prio: 5, act: NPCA_PHOTO, fill: true }               # the story's words (NpcTalk.say)
sighting { prio: 4, chance: 30, fill: true }                # considered three times in ten
water { prio: 3, act: NPCA_WATER, text: "Boil it, even up here." }
hello { prio: 1, text: "Morning.", choices: [{ text: "Any fish?", line: "fish", code: 7 }] }

The highest prio with anything to say wins, each line of it in table order given its chance; a fill line's words are NpcTalk.say(p, line), and "" means it has nothing true to say now. npc_talk picks one (a Talked fact); npc_choose answers a choice with the line it names (a Talked fact carrying the choice's code). A vendor's greeting is NpcTalk.greeting(p).

The ports

export port NpcWorld {       # every member has a default: a flat dry field at noon, one player, nobody wanted
  ground, water, slope: fn(float, float) -> float
  allowed: fn(float, float) -> bool                  # may a person stop here
  push: fn(x, z, r, feet, head) -> bool, pushed_x, pushed_z   # a walker slid clear of still things (r 0.35)
  clear: fn(ax, ay, az, bx, by, bz) -> bool          # no still thing between: npc_line_ok asks it at 1 m
  hour: fn() -> float, day: fn() -> int              # the clock
  players: fn() -> int, player_on: fn(int) -> bool, player_x / player_z: fn(int) -> float
  want: fn() -> int, extra: fn() -> int              # the census: how many, and a kind brought out regardless (-1)
  origin_x / origin_z: fn() -> float                 # where anyone goes when nowhere else will do
  next_id: fn() -> int, body_of: fn(int) -> int      # an id across machines; a look seed's body
  taken: fn(string) -> bool                          # a name the place keeps
  born / gone: fn(NpcPerson) -> void                 # draw it, stop drawing it
  way: fn(NpcPerson, x, z) -> bool, way_x, way_z      # the next corner of its way toward (x, z)
}
export port NpcTalk { say: fn(NpcPerson, int) -> string, greeting: fn(NpcPerson) -> string }

A person walks by the world's way where the world has one. way is asked for the next corner toward where it is going - every half second, on reaching the corner, and at once for a new target - and the person walks corner to corner, but begins its errand only at the target itself. With no answer (the default) it walks straight and steps round what is in the way, as before; the step round and the twenty seconds' give-up stay as the fallback. Maroon Lake binds way to its navmesh by a person's taste.

API

NpcPerson, npc_walkers(), npc_posts(), npc_at(slot), npc_post(i), npc_by_id(id), npc_count(), npc_max()	the people (goal, subj, note, note_h, flags are the game's)
npc_config(max), npc_seed(n), npc_rnd(), npc_between(lo, hi), npc_secs(lo, hi)	the cap and the package's own dice
npc_tick(dt), npc_posts_tick(dt), npc_census_now(), npc_hold(on), npc_reset(), npc_clear()	a step where the place is run (or of the posts alone), the census at once, held still, a new trip, a new place
npc_spawn(kind), npc_place(kind, x, z, yaw, name, look), npc_retire(p), npc_start_near(p, x, z, r0, r1), npc_set_at(p, x, z)	making and leaving
npc_go(p, x, z, act, secs), npc_do(p, act, secs), npc_face(p, x, z), npc_face_ahead(p), npc_set_home_face(p, x, z), npc_plan(p), npc_steps(p, steps), npc_step_go(p, step, x, z), npc_wander(p)	the routine
npc_walk(p, dt), npc_act(p, dt), npc_notice(p)	a person's step
npc_walkable(x, z), npc_line_ok(ax, az, bx, bz), npc_spot_near(x, z, d0, d1), npc_toward(ax, az, bx, bz, d), npc_shore(x, z, r), npc_px(), npc_pz(), npc_wx(), npc_wz()	the ground
npc_near(x, z), npc_near_i(), npc_d(...), npc_wrap(a)	the nearest player, distances, angles
npc_pick_name(body), npc_name_used(n), npc_name_clashes()	names
npc_talk(p, player), npc_line_for(p), npc_words(p, line), npc_said(), npc_choose(p, line, c, player), npc_talked_today(p), npc_greeting(p)	talk
npc_mirror(on), npc_mirroring(), npc_put(slot, id, kind, look, seed, name, hx, hz), npc_heard(slot, x, y, z, yaw, speed, act, stalk), npc_heard_lately(p), npc_mirror_tick(dt)	a guest's copy of the host's people
npc_facts() -> Queue<NpcFact>	NPC_F_GREETED (player), NPC_F_TALKED (player, line, choice), NPC_F_ARRIVED (act), NPC_F_STUCK (how - NPC_STUCK_DETOUR, _RETRY, _GAVE_UP - at x, z: the way failed it and it fell back)
npc_system() -> System	"npc", PH_SIMULATE, a reset and no tick; nothing saved

Tests

ludic test packages/ludic.npc