---
title: "Projectile Patterns: API"
package: "@phaser-ae/projectile-patterns"
tier: Free
version: 3.0.0-3
released: 2026-10-14
updated: 2026-10-20
description: "Aimed, fan, ring, spiral, burst and staged volleys of projectiles, with swept hits, piercing, ricochet, homing and graze events, independent of any renderer."
url: https://phaser.io/packs/projectile-patterns/api
site: Phaser - https://phaser.io
---

# Projectile Patterns: API

`@phaser-ae/projectile-patterns` — Aimed, fan, ring, spiral, burst and staged projectiles with swept hits, piercing, ricochet, homing and graze.

## The pack

### `projectilePatterns`

```ts
function projectilePatterns():Pack<{projectilePatterns:typeof rules}>
```

Install renderer-independent projectile patterns policies.

## Helpers

### `createProjectiles`

```ts
function createProjectiles()
```

Create an empty projectile system.

### `patternShots`

```ts
function patternShots(p: ProjectilePattern, aim = 0): PatternShot[]
```

Pure pattern schedule, relative to emission. Aim is in radians; angles are never renderer coordinates.

## Classes

### `Projectiles`

```ts
class Projectiles
```

Owns emission, swept collisions, lifetime and per-projectile hit/graze sets. Damage is emitted for a combat adapter.

- `time: number` — Seconds elapsed on this projectile clock.
- `shots: Projectile[]` — The projectiles in flight; those still waiting to launch are not listed.
- `readonly events: ProjectileEvent[]` — Events since the last `drain`, in order.
- `emit(pattern: ProjectilePattern, origin: Point, aim: number, team: string, damage = 1): number[]` — Schedule a volley from `origin` along `aim` (radians) for `team`, each projectile carrying `damage` (default 1). Shots with no delay launch at once. Returns the ids of every projectile it schedules. Throws on a pattern value outside its bounds or a non-finite `damage`.
- `tick(dt: number, targets: readonly ProjectileTarget[] = [], walls: readonly Rect[] = [], graze = 8)` — Advance by `dt` seconds (0 to 10) in substeps of at most 1/120 s: launch due shots, move them, hit living targets of other teams, stop or bounce them at `walls` (rectangles whose `x`, `y` are the top-left corner) and expire them. A near miss within `graze` world units (default 8) of a target's edge raises a `graze` event. Throws when `dt` is outside 0 to 10 or `graze` is negative.
- `drain()` — Take the pending events and clear them.
- `clear()` — Remove every projectile, pending launch and event; the clock and id counter keep their values.
- `snapshot()` — A plain copy of the clock, the id counter, the projectiles and the pending launches.
- `restore(s: ReturnType<Projectiles['snapshot']>)` — Replace the state with a snapshot's and clear the events. Throws when a time, id counter, position or life in it is out of range.

## Types

### `PatternKind`

```ts
type PatternKind = 'aimed' | 'fan' | 'ring' | 'spiral' | 'burst' | 'staged'
```

How a volley's shots are arranged: `aimed` (all along the aim), `fan` (spread across an arc), `ring` (evenly round a circle), `spiral` (one at a time, each turned from the last), `burst` (one at a time along the aim) or `staged` (several rings in turn).

### `PatternShot`

```ts
interface PatternShot
```

One shot of a volley's schedule, relative to emission.

- `at: number` — Seconds after emission that it launches.
- `angle: number` — Launch direction in radians: the velocity is (cos, sin) times the speed, so 0 points along +x.

### `Projectile`

```ts
interface Projectile extends Point
```

A projectile in flight; `x` and `y` are its position in world units.

- `id: number` — Unique id within its `Projectiles`, counting up from 1.
- `team: string` — The team that fired it; targets of the same team are ignored.
- `vx: number` — Velocity along x, world units a second.
- `vy: number` — Velocity along y, world units a second.
- `rot: number` — Heading in radians, `atan2(vy, vx)`, for facing a sprite.
- `r: number` — Collision radius, world units.
- `life: number` — Seconds of life left; it is removed at 0.
- `damage: number` — Damage each `hit` event carries.
- `pierce: number` — Further targets it can pass through before a hit stops it.
- `ricochet: number` — Wall reflections it has left.
- `homing: number` — Turn rate towards the nearest living target of another team, radians a second; 0 flies straight.
- `hits: string[]` — Ids of the targets it has already hit; each is hit at most once.
- `grazed: string[]` — Ids of the targets it has already grazed; each is grazed at most once.

### `ProjectileEvent`

```ts
interface ProjectileEvent
```

Something that happened to a projectile, for a combat adapter, sound or effects.

- `kind: 'spawn' | 'hit' | 'graze' | 'bounce' | 'expired'` — What happened: `spawn` (launched), `hit`, `graze` (a near miss), `bounce` (off a wall) or `expired` (life ran out or it was stopped).
- `projectile: number` — Id of the projectile.
- `target: string` — Id of the target hit or grazed; an empty string for the other kinds.
- `damage: number` — Damage dealt by a `hit`; 0 for the other kinds.
- `time: number` — Seconds on the `Projectiles` clock when it happened.

### `ProjectilePattern`

```ts
interface ProjectilePattern
```

A volley: its arrangement, size, speed and what each projectile carries.

- `kind: PatternKind` — The arrangement of the shots.
- `count: number` — Shots per volley, or per ring for `ring` and `staged`; a whole number from 1 to 256.
- `speed: number` — Projectile speed, world units a second; above 0.
- `spread?: number` — `fan` only: the arc across which the shots spread, in radians from 0 to 2π, centred on the aim. Default 0.7.
- `interval?: number` — Seconds between launches for `burst` and `spiral` (between shots) and `staged` (between rings). Default 0.12.
- `stages?: number` — `staged` only: the number of rings, a whole number from 1 to 32. Default 3.
- `rotation?: number` — Radians each step turns: between successive shots for `spiral` (default 0.4) and between rings for `staged` (default 0.24). Ignored by the other kinds.
- `radius?: number` — Collision radius of each projectile, world units, at least 0.01. Default 4.
- `life?: number` — Seconds a projectile lives, from 0.001 to 60. Default 5.
- `pierce?: number` — Further targets a projectile passes through after its first hit, a whole number from 0 to 100. Default 0, which stops it at the first.
- `ricochet?: number` — Wall reflections a projectile has, a whole number from 0 to 100. Default 0, which stops it at the first wall.
- `homing?: number` — Turn rate towards the nearest living target of another team, radians a second; 0 flies straight. Default 0.

### `ProjectileTarget`

```ts
interface ProjectileTarget extends Point
```

Something projectiles can hit: a circle at `x`, `y` in world units.

- `id: string` — Unique id, reported in events.
- `team: string` — Its team; projectiles ignore targets of their own team.
- `r: number` — Collision radius, world units.
- `alive: boolean` — Whether it can be hit; a target that is not alive is skipped.

---

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