---
title: "Endless lane crossing: API"
package: "@phaser-ae/crossy-road"
tier: Free
version: 3.0.0-3
released: 2026-10-14
updated: 2026-10-20
description: "An endless lane-crossing hopper: hop across grass, roads of traffic, rivers of logs and lily pads, and railways, on a strip of rows generated from a grammar of data."
url: https://phaser.io/packs/crossy-road/api
site: Phaser - https://phaser.io
---

# Endless lane crossing: API

`@phaser-ae/crossy-road` — Hop a chicken across an endless strip of grass, roads, rivers of logs and lily pads, and railways, before the eagle comes, as in Crossy Road.

## The pack

### `crossyRoad`

```ts
function crossyRoad(): Pack<{ crossyRoad: CrossyRoadApi }>
```

The `crossy-road` pack: `game.crossyRoad`, Crossy Road's rules as a row grammar on lane-control. No options.

## Helpers

### `createCrossyAutopilot`

```ts
function createCrossyAutopilot(game: CrossyRoadGame, options: CrossyAutopilotOptions = {}): CrossyAutopilot
```

A crossing's autopilot. It only reads `game`; give its hop to `game.hop`.

### `createCrossyRoad`

```ts
function createCrossyRoad(options: CrossyOptions = {}): CrossyRoadGame
```

Start a crossing. Throws, with every fault, on options it refuses.

### `crossyRows`

```ts
const crossyRows: Record<string, CrossyRowKind>
```

The built-in row kinds: Crossy Road's grass, roads, rivers and railways.

### `crossySegments`

```ts
const crossySegments: CrossySegment[]
```

The built-in segments: a start, then grass, roads, highways, rivers, ponds and railways, harder further on.

### `validateCrossyRoad`

```ts
function validateCrossyRoad(options: CrossyOptions = {}): string[]
```

Check a crossing's options. Empty when it can be played.

## Types

### `CrossyAutopilot`

```ts
interface CrossyAutopilot
```

A player that picks the next hop.

- `next(): CrossyMove | null` — The hop to make now, or null to wait. Call it before each step.

### `CrossyAutopilotOptions`

```ts
interface CrossyAutopilotOptions
```

How the autopilot plans.

- `search?: number` — Seconds the route search looks ahead at most. Default 7.
- `tick?: number` — Seconds between steps of the search. Default 0.1.
- `breadth?: number` — States the search keeps per step at most. Default 400.

### `CrossyEagle`

```ts
interface CrossyEagle
```

The eagle: it takes a chicken that waits too long or falls behind the screen.

- `idle: number` — Seconds without a step forward before it comes. Default 8.
- `creep: number` — Rows the screen creeps forward a second. Default 0.25.
- `behind: number` — Rows behind the screen's line that it comes at. Default 3.

### `CrossyEvent`

```ts
type CrossyEvent = | { kind: 'hop'; move: CrossyMove } | { kind: 'bump'; move: CrossyMove } | { kind: 'land'; row: number; on: 'ground' | 'log' | 'pad' } | { kind: 'coin'; row: number; total: number } | { kind: 'forward'; row: number } | { kind: 'bell'; row: number } | { kind: 'over'; cause: 'car' | 'train' | 'water' | 'drift' | 'eagle' }
```

Something that happened.

### `CrossyGrass`

```ts
interface CrossyGrass
```

Grass: trees in the way, coins to take.

- `kind: 'grass'` — Row type tag; always `'grass'`.
- `trees?: number` — Chance a cell has a tree, 0 to 1. A path through is always kept clear. Default 0.2.
- `coins?: number` — Chance the row has a coin. Default 0.15.
- `name?: string` — Presenter name.

### `CrossyMove`

```ts
type CrossyMove = 'up' | 'down' | 'left' | 'right'
```

A hop.

### `CrossyMover`

```ts
interface CrossyMover
```

A moving thing, as drawn: x is its left edge in playable columns (it may be off either side).

- `id: string` — Unique within a view: the row index and the piece's lane id, such as `'12:p0'`; a train is `'12:train'`.
- `row: number` — Index of the row it travels on.
- `kind: string` — Presenter name from its template, such as `'car'`, `'truck'` or `'log'`; `'train'` for a train.
- `x: number` — Left edge in playable columns, 0 at the left playable column; below 0 or at least `width` while out in the overhang.
- `length: number` — Length in cells.

### `CrossyOptions`

```ts
interface CrossyOptions
```

A crossing's options.

- `seed?: number` — The seed. Default 1.
- `width?: number` — Playable columns. Default 9.
- `overhang?: number` — Columns off each side where traffic and logs run on, out of reach. Default 4.
- `rows?: Record<string, CrossyRowKind>` — The row kinds, by name. Default `crossyRows`.
- `segments?: CrossySegment[]` — The segments. Default `crossySegments`.
- `opening?: string[]` — Segments played first. Default `['start']` with the built-in segments.
- `hopTime?: number` — Seconds a hop takes. Default 0.14.
- `radius?: number` — The chicken's half width, in cells. Default 0.3.
- `eagle?: Partial<CrossyEagle>` — The eagle.
- `pace?: number` — Speed factor for every moving row: a harder game. Default 1.

### `CrossyPiece`

```ts
interface CrossyPiece
```

A moving piece's template: what it is and how long, in cells. Several lengths pick by seed.

- `kind: string` — Presenter name: 'car', 'truck', 'log'.
- `length: CrossyRange` — Length in cells.

### `CrossyRail`

```ts
interface CrossyRail
```

A railway: lights flash, then a train goes through.

- `kind: 'rail'` — Row type tag; always `'rail'`.
- `period: CrossyRange` — Seconds between trains.
- `warning?: number` — Seconds the lights flash before a train. Default 1.6.
- `length?: number` — The train's length in cells. Default 14.
- `speed?: number` — Its speed, cells a second. Default 32.
- `name?: string` — Presenter name.

### `CrossyRange`

```ts
type CrossyRange = number | [number, number]
```

A range picked by seed: one value, or `[min, max]`.

### `CrossyRiver`

```ts
interface CrossyRiver
```

A river: the only footing is the logs (drifting) or lily pads (still).

- `kind: 'river'` — Row type tag; always `'river'`.
- `speed?: CrossyRange` — Cells a second for logs; direction picked by seed. Ignored with `pads`.
- `count: CrossyRange` — How many logs, or lily pads.
- `pieces?: CrossyPiece[]` — Log templates. Ignored with `pads`.
- `pads?: boolean` — Still lily pads, one cell each, instead of logs.
- `gap?: number` — Least water between logs. Default 1.2.
- `name?: string` — Presenter name.

### `CrossyRoad`

```ts
interface CrossyRoad
```

A road: traffic that kills.

- `kind: 'road'` — Row type tag; always `'road'`.
- `speed: CrossyRange` — Cells a second; direction picked by seed.
- `count: CrossyRange` — How many vehicles.
- `pieces: CrossyPiece[]` — Vehicle templates, used in turn.
- `gap?: number` — Least clear cells between vehicles. Default 1.5.
- `coins?: number` — Chance the row has a coin. Default 0.1.
- `name?: string` — Presenter name.

### `CrossyRoadApi`

```ts
interface CrossyRoadApi
```

What the `crossy-road` pack adds to a game: `game.crossyRoad`.

- `create: typeof createCrossyRoad` — Start a crossing.
- `validate: typeof validateCrossyRoad` — Check a crossing's options; empty when it can be played.
- `rows: typeof crossyRows` — The built-in row kinds.
- `segments: typeof crossySegments` — The built-in segments.
- `autopilot: typeof createCrossyAutopilot` — A player that looks ahead, for an attract mode or a test.

### `CrossyRoadGame`

```ts
interface CrossyRoadGame
```

A crossing.

- `readonly state: CrossyState` — Where the chicken is.
- `readonly options: Readonly<{ width: number; overhang: number; hopTime: number; radius: number; eagle: CrossyEagle; pace: number }>` — The options, defaults filled in.
- `hop(move: CrossyMove): boolean` — A hop, if the way is open and the chicken is not mid-hop; returns whether it went.
- `step(dt: number): void` — Advance `dt` seconds, in fixed steps of 1/120 s.
- `row(index: number): CrossyRow` — The row at an index (generated on demand).
- `view(behind?: number, ahead?: number): CrossyView` — What is where.
- `drain(): CrossyEvent[]` — Events since the last call.
- `snapshot(): CrossySave` — The run as plain JSON.
- `restore(save: CrossySave): void` — Pick up a saved run made with the same options.
- `clone(): CrossyRoadGame` — A separate run with the same options at the same point.

### `CrossyRow`

```ts
interface CrossyRow
```

A row as laid: its kind and what is on it.

- `index: number` — Its index: 0 is the start.
- `name: string` — Its kind's name.
- `kind: CrossyRowKind['kind']` — Its kind.
- `trees: number[]` — Trees, by column (grass).
- `path: number` — A column the generator keeps open: on grass no tree stands on it or on the path's column in the rows either side, and a pond has a pad on it and on the column of the row before.
- `coin: number | null` — A coin's column, or null.
- `lane: LaneDefinition | null` — Its moving lane (road and river logs): lane-control's definition, positions at time 0, in lane cells.
- `pads: number[]` — Lily pads, by column (river with pads).
- `rail: { period: number; offset: number; warning: number; length: number; speed: number } | null` — Railway timing: seconds between trains, and where in that it starts.

### `CrossyRowKind`

```ts
type CrossyRowKind = CrossyGrass | CrossyRoad | CrossyRiver | CrossyRail
```

A kind of row.

### `CrossySave`

```ts
interface CrossySave
```

A crossing saved as plain JSON. The rows are not in it: they follow from the seed.

- `seed: number` — The seed of the crossing; `restore` refuses a save with a different seed.
- `width: number` — Playable columns of the crossing; `restore` refuses a save with a different width.
- `state: CrossyState` — The chicken and run state when the save was made.
- `taken: number[]` — Indices of the rows whose coin has already been picked up.

### `CrossySegment`

```ts
interface CrossySegment
```

A run of rows: row kinds by name, each repeated `count` times.

- `id: string` — Its name.
- `rows: (string | { row: string; count: CrossyRange })[]` — The rows, in order.
- `weight?: number` — Likelihood against the others. Default 1; 0 is for `opening` only.
- `from?: number` — The first row it may start at. Default 0.
- `until?: number` — The last row it may start at. Default no limit.
- `follows?: string[]` — May only come straight after one of these segments.
- `never?: string[]` — Never comes straight after one of these.

### `CrossyState`

```ts
interface CrossyState
```

Where the chicken is and how the run stands.

- `x: number` — Across, in columns (0 is the left edge's column); continuous while on a log.
- `row: number` — Its row; between two rows while hopping.
- `furthest: number` — The furthest row reached: the score.
- `coins: number` — Coins.
- `time: number` — Seconds run.
- `idle: number` — Seconds since the last step forward.
- `screen: number` — The screen's line, in rows: it creeps forward and follows the chicken.
- `hop: { fromX: number; fromRow: number; toX: number; toRow: number; t: number; move: CrossyMove } | null` — The hop in the air: from, to, and how far through.
- `facing: CrossyMove` — The way it faces.
- `alive: boolean` — False once the run is over.
- `cause: 'car' | 'train' | 'water' | 'drift' | 'eagle' | null` — Why it ended.

### `CrossyView`

```ts
interface CrossyView
```

What is where, for a presenter.

- `chicken: CrossyState` — The chicken.
- `rows: CrossyRow[]` — The rows from `behind` to `ahead`.
- `movers: CrossyMover[]` — Cars, trucks and logs where they are now.
- `trains: CrossyMover[]` — Trains where they are now, and railways whose lights flash.
- `warnings: number[]` — Rows whose lights are flashing.
- `width: number` — Playable columns, and the overhang either side.
- `overhang: number` — Columns of overhang either side of the playable width, where movers run out of reach.

---

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