---
title: "Paths and walkers: API"
package: "@phaser-ae/path"
tier: Free
version: 3.0.0-3
released: 2026-10-14
updated: 2026-10-19
description: "Moves things along any 2D curve at an even speed, for swooping enemy waves, looping platforms, spiralling bosses and camera rides."
url: https://phaser.io/packs/path/api
site: Phaser - https://phaser.io
---

# Paths and walkers: API

`@phaser-ae/path` — Move things along any geometry curve at even speed: walkers with loop, yoyo, ease and align; game.path.follow(h, shape).

## The pack

### `path`

```ts
function path(): Pack<{ path: PathApi }, PathTopics>
```

The path pack: walkers along any geometry shape (baked by arc length so speed is even), and `follow` to drive objects by them. Headless.

## Types

### `PathApi`

```ts
interface PathApi
```

`game.path`.

- `walker(shape: Shape, opts?: WalkOptions): Walker` — A headless walker on a shape: the game reads `x y angle` and does what it likes with them.
- `follow(h: Handle, shape: Shape, opts?: WalkOptions): Walker` — Drive `h` along `shape` each step until it ends or is stopped; the walker is returned and the object is moved (and rotated with `align`). Scene-scoped; a second `follow` on the same object replaces the first.
- `stop(h: Handle): void` — Stop driving `h`. Safe when it is not followed.
- `walkerOf(h: Handle): Walker | null` — The walker driving `h`, or null.
- `readonly count: number` — Objects being driven.

### `PathTopics`

```ts
interface PathTopics
```

Signals, once per step.

- `'path.end': { id: string }` — A followed object reached the end of its path (loop 'none').
- `'path.lap': { id: string; laps: number }` — A followed object wrapped or turned (loop / yoyo).

### `Walker`

```ts
interface Walker
```

A position moving along a curve. `update(dt)` advances it; `follow` calls that for you each step.

- `t: number` — Progress along the curve, 0..1 by length (after the ease). Set it to jump.
- `readonly x: number` — Current x.
- `readonly y: number` — Current y.
- `readonly angle: number` — Direction of travel, degrees.
- `readonly distance: number` — World units travelled this pass.
- `readonly length: number` — The curve's length.
- `readonly done: boolean` — Finished (loop 'none' reached the end).
- `readonly laps: number` — Passes completed (loop or yoyo turns).
- `readonly reversed: boolean` — Moving backwards (yoyo's return leg).
- `paused: boolean` — Hold.
- `speed: number` — Live speed, units/s.
- `update(dt: number): boolean` — Advance by `dt` seconds. Returns true while moving.
- `reset(): void` — Back to the start (or `at`).

### `WalkOptions`

```ts
interface WalkOptions
```

How a walker moves.

- `speed?: number` — World units per second along the curve. Default 100.
- `duration?: number` — Or: seconds for the whole curve (overrides `speed`).
- `loop?: 'none' | 'loop' | 'yoyo'` — What happens at the end: stop, wrap to the start, or turn back. Default 'none'.
- `ease?: EaseName | EaseFn` — An ease over each pass (by `duration` or by length at `speed`). Default linear.
- `at?: number` — Start this far along, 0..1. Default 0.
- `relative?: boolean` — The curve is relative to the walker's start point (its handle's position when `follow` begins). Default false: world coordinates.
- `align?: boolean` — Set the followed object's rotation to the direction of travel (+ `alignOffset` degrees). Default false.
- `alignOffset?: number` — Degrees added when aligning. Default 0.
- `samples?: number` — Arc-length samples for the bake. Default 128 (more for long or wiggly curves).
- `paused?: boolean` — Start paused. Default false.

---

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