feat: robins

This commit is contained in:
Dan Finch 2026-08-07 13:37:30 +02:00
parent a4490f7a20
commit bd88d3cbd6
12 changed files with 159 additions and 54 deletions

View file

@ -57,8 +57,8 @@ export type RenderConfig = {
* color depth, dither, vertex snap, and filtering from crunchy PS1 to clean. */
export namespace RenderConfig {
export const standard: RenderConfig = {
internalWidth: 384,
internalHeight: 216,
internalWidth: 640,
internalHeight: 360,
upscaleFilter: "nearest",
colorDepth: 5,
dither: 1,

View file

@ -5,23 +5,25 @@ import { STRIDE, type Mesh } from "./Mesh"
const TAU = Math.PI * 2
/** A roaming creature drawn as a moving low-poly mesh (unlike the static baked
* world). Two kinds, told apart by silhouette + motion:
* frog -- squat, ground-bound, sits then springs a ballistic hop.
* bee -- small, hovers and darts through the air, wings out.
* world). Three kinds, told apart by silhouette + motion:
* frog -- squat, ground-bound, sits then springs a ballistic hop.
* bee -- small, hovers and darts through the air, wings out.
* robin -- round red-breasted bird; mostly hops like a frog, but now and then
* takes off on a short powered flight to a new perch.
*
* Unlike `Tree`/`Boulder` (baked once into world-space chunks), a mob's geometry
* is a **canonical local-space mesh** built once per kind (front = +Z, frog feet
* / bee body at the origin); the live `position`/`heading`/`scale` are turned
* is a **canonical local-space mesh** built once per kind (front = +Z, frog/robin
* feet / bee body at the origin); the live `position`/`heading`/`scale` are turned
* into a per-frame model matrix by the renderer. All wander state lives here so
* `update` is a pure stepping function of the mob + dt (deterministic via the
* evolving `seed`), which keeps the sim on the main thread and cloneable-free. */
export type MobKind = "frog" | "bee"
export type MobKind = "frog" | "bee" | "robin"
export type Mob = {
kind: MobKind
/** Leash anchor (where it was scattered); wandering is pulled back toward it. */
home: Vec3
/** Live feet-center (frog) / body-center (bee), advanced each frame. */
/** Live feet-center (frog/robin) / body-center (bee), advanced each frame. */
position: Vec3
/** Facing yaw; the mesh's front is local +Z, so world dir = (sin h, 0, cos h). */
heading: number
@ -29,16 +31,17 @@ export type Mob = {
scale: number
/** Evolving RNG state (mutated by `update`) -- keeps the sim deterministic. */
seed: number
/** Horizontal velocity (frog: only mid-hop; bee: cruise). */
/** Horizontal velocity (frog/robin: mid-hop or -flight; bee: cruise). */
vx: number
vz: number
/** Vertical velocity (frog ballistic hop; bee stays 0, it uses a bob). */
/** Vertical velocity (frog/robin ballistic hop/flight; bee stays 0, uses a bob). */
vy: number
/** Countdown to the next decision (frog: next hop; bee: next heading change). */
/** Countdown to the next decision (frog/robin: next hop; bee: next heading change). */
timer: number
/** Accumulated time, for the bee's hover bob. */
/** Per-kind scratch clock: the bee's hover-bob phase; the robin's remaining
* powered-flight cruise time (>0 while gliding between perches). */
phase: number
/** Frog only: resting on the ground vs airborne in a hop. */
/** Frog/robin: resting on the ground vs airborne (a hop or a flight). */
grounded: boolean
}
@ -56,14 +59,27 @@ const BEE_TURN_SPAN = 1
const BEE_HOVER = 1.1
const BEE_BOB_AMP = 0.18
const BEE_BOB_FREQ = 3
const ROBIN_LEASH = 6
const ROBIN_REST_MIN = 0.5
const ROBIN_REST_SPAN = 1.3
const ROBIN_HOP_SPEED = 1.4
const ROBIN_HOP_IMPULSE = 2.6
/** Fraction of a robin's moves that are a flight rather than a ground hop. */
const ROBIN_FLY_CHANCE = 0.35
const ROBIN_FLY_SPEED = 4.5
const ROBIN_FLY_IMPULSE = 3.5
const ROBIN_CRUISE = 0.8
const ROBIN_GRAVITY = 14
export namespace Mob {
/** Advance one mob by `dt` seconds, sampling `terrain` for ground height. */
export function update(mob: Mob, dt: number, terrain: Terrain): void {
if (mob.kind === "frog") {
frog(mob, dt, terrain)
} else {
} else if (mob.kind === "bee") {
bee(mob, dt, terrain)
} else {
robin(mob, dt, terrain)
}
}
@ -72,19 +88,21 @@ export namespace Mob {
export function build(kind: MobKind, mesh: Mesh): void {
if (kind === "frog") {
buildFrog(mesh)
} else {
} else if (kind === "bee") {
buildBee(mesh)
} else {
buildRobin(mesh)
}
}
/** Local bounding radius (pre-scale), for building the per-frame cull AABB. */
export function boundingRadius(kind: MobKind): number {
return kind === "frog" ? 0.7 : 0.5
return kind === "frog" ? 0.7 : kind === "robin" ? 0.45 : 0.5
}
/** Local body height (pre-scale), for the top of the stand-on collider. */
export function bodyHeight(kind: MobKind): number {
return kind === "frog" ? 0.6 : 0.5
return kind === "frog" ? 0.6 : kind === "robin" ? 0.55 : 0.5
}
// --- Simulation ---------------------------------------------------------
@ -133,6 +151,49 @@ export namespace Mob {
mob.position.y = ground + BEE_HOVER + Math.sin(mob.phase * BEE_BOB_FREQ) * BEE_BOB_AMP
}
function robin(mob: Mob, dt: number, terrain: Terrain): void {
if (mob.grounded) {
mob.timer -= dt
mob.position.y = Terrain.height(terrain, mob.position.x, mob.position.z)
if (mob.timer > 0) {
return
}
// Decide the next move: usually a short ground hop, sometimes a longer
// powered flight -- higher + faster off the mark, then a flat glide (see
// the cruise branch below) before settling onto a new perch.
mob.heading = wanderHeading(mob, ROBIN_LEASH, 1)
const fly = nextRand(mob) < ROBIN_FLY_CHANCE
const speed = fly ? ROBIN_FLY_SPEED : ROBIN_HOP_SPEED
mob.vx = Math.sin(mob.heading) * speed
mob.vz = Math.cos(mob.heading) * speed
mob.vy = fly ? ROBIN_FLY_IMPULSE : ROBIN_HOP_IMPULSE
mob.phase = fly ? ROBIN_CRUISE : 0
mob.grounded = false
return
}
if (mob.phase > 0) {
// In flight: bleed vertical speed toward level so it glides roughly flat
// (a bird crossing the clearing), not a lob; gravity resumes once cruise ends.
mob.phase -= dt
mob.vy += (0 - mob.vy) * Math.min(1, dt * 6)
} else {
mob.vy -= ROBIN_GRAVITY * dt
}
mob.position.x += mob.vx * dt
mob.position.y += mob.vy * dt
mob.position.z += mob.vz * dt
const ground = Terrain.height(terrain, mob.position.x, mob.position.z)
if (mob.position.y <= ground && mob.vy < 0) {
mob.position.y = ground
mob.vx = 0
mob.vy = 0
mob.vz = 0
mob.phase = 0
mob.grounded = true
mob.timer = ROBIN_REST_MIN + nextRand(mob) * ROBIN_REST_SPAN
}
}
/** A new heading: free wander when inside the leash, else biased back toward
* home so the mob never drifts off into the peaks (`jitter` = the random cone
* half-width in radians layered on top of the homeward bearing). */
@ -179,6 +240,19 @@ export namespace Mob {
wing(mesh, -1, 0.83, 0.99, 0, 1)
}
function buildRobin(mesh: Mesh): void {
// Round European robin: plump brown body, an orange-red breast bulging on the
// front, a round brown head with two dark eyes + a small dark beak, short tail.
// UVs: robin texture is brown (left), orange breast (mid), dark eye/beak (right).
ellipsoid(mesh, 0, 0.26, 0, 0.26, 0.26, 0.3, 6, 4, 0, 0.38, 0, 1) // body (brown)
ellipsoid(mesh, 0, 0.18, 0.17, 0.22, 0.22, 0.16, 5, 4, 0.42, 0.68, 0, 1) // breast (orange)
ellipsoid(mesh, 0, 0.48, 0.14, 0.18, 0.18, 0.18, 5, 4, 0, 0.38, 0, 1) // head (brown)
ellipsoid(mesh, 0.09, 0.52, 0.26, 0.03, 0.03, 0.03, 3, 2, 0.85, 0.99, 0, 1) // eye
ellipsoid(mesh, -0.09, 0.52, 0.26, 0.03, 0.03, 0.03, 3, 2, 0.85, 0.99, 0, 1) // eye
ellipsoid(mesh, 0, 0.47, 0.35, 0.03, 0.025, 0.09, 3, 2, 0.85, 0.99, 0, 1) // beak (dark)
ellipsoid(mesh, 0, 0.26, -0.32, 0.09, 0.05, 0.16, 4, 2, 0, 0.38, 0, 1) // tail (brown)
}
/** A UV-rected ellipsoid (pole on Y), faceted like the boulders. */
function ellipsoid(
mesh: Mesh,