RotationBehavior<DataType, ParticleType>

Behavior used to control the rotation of particles over their lifetime.

Behavior supports four modes, a static mode where a single value is applied to all particles, a list mode where values are interpolated over the particle's lifetime based on a provided list, a direction mode where the rotation is set based on the particle's movement direction, and an acceleration mode where the rotation changes over time based on an acceleration value.

See

• DirectionConfigType for direction configuration options.
• AccelerationConfigType for acceleration configuration options.
• BehaviorStaticConfig for static configuration options.
• BehaviorSingleListConfig for list configuration options.

Example

// Apply a static rotation of 45 degrees to all particles.
rotationBehavior.applyConfig({
    mode: "static",
    value: Math.PI / 4,
});

// Interpolate particle rotation from 0 to 360 degrees over lifetime.
rotationBehavior.applyConfig({
    listData: [
        { time: 0.0, value: 0 },
        { time: 1.0, value: Math.PI * 2 },
    ],
    mode: "list",
});

Extends

• EmitterBehavior<RotationBehaviorConfig, DataType, ParticleType>

Type Parameters

DataType

DataType extends BaseParticleData

Type describing the data object stored on particles.

ParticleType

ParticleType extends IEmitterParticle<DataType> = IEmitterParticle<DataType>

Type describing the particle used within the emitter.

Implements

• InitBehavior<DataType, ParticleType>
• UpdateBehavior<DataType, ParticleType>

Constructors

Constructor

new RotationBehavior<DataType, ParticleType>(emitter): RotationBehavior<DataType, ParticleType>;

Creates a new RotationBehavior.

Parameters

emitter

Emitter<DataType, ParticleType>

Emitter instance this behavior belongs to.

Returns

RotationBehavior<DataType, ParticleType>

Overrides

EmitterBehavior.constructor

Accessors

acceleration

Get Signature

get acceleration(): number;

Rotation acceleration applied over time (used for acceleration mode).

Returns

number

Set Signature

set acceleration(value): void;

Parameters

value

number

Returns

void

---

list

Get Signature

get list(): NumberList;

Number list used to interpolate rotation values over particle lifetime.

A behavior will always have a list, even when not using list-based configuration, but the list might not be initialized and will be empty in that case.

Returns

NumberList

---

mode

Get Signature

get mode(): RotationBehaviorMode;

Current mode used by the behavior.

Returns

RotationBehaviorMode

Set Signature

set mode(value): void;

Parameters

value

RotationBehaviorMode

Returns

void

---

startRotation

Get Signature

get startRotation(): number;

Initial rotation value for the particle (used for acceleration mode).

Returns

number

Set Signature

set startRotation(value): void;

Parameters

value

number

Returns

void

---

staticValue

Get Signature

get staticValue(): number;

Static rotation value applied to all particles.

Returns

number

Set Signature

set staticValue(value): void;

Parameters

value

number

Returns

void

---

updateOrder

Get Signature

get updateOrder(): BehaviorOrder;

Defines at which step of the update cycle the behavior is applied.

• initial: Earliest step, useful when other behaviors depend on this behavior.
• normal: Default step for most behaviors.
• late: Latest step, useful for behaviors that should override others or depend on their properties.

Returns

BehaviorOrder

Implementation of

UpdateBehavior.updateOrder

Overrides

EmitterBehavior.updateOrder

Methods

applyConfig()

applyConfig(config): void;

Reset the behavior and apply the provided configuration.

Parameters

config

RotationBehaviorConfig

Behavior configuration.

Returns

void

Implementation of

UpdateBehavior.applyConfig

Overrides

EmitterBehavior.applyConfig

---

getConfig()

getConfig():
  | RotationBehaviorConfig
  | undefined;

Retrieve the current behavior properties as a configuration object. If the behavior is inactive, undefined is returned.

Returns

| RotationBehaviorConfig | undefined

Behavior configuration object or undefined if inactive.

Implementation of

UpdateBehavior.getConfig

Overrides

EmitterBehavior.getConfig

---

init()

init(particle): void;

Initialize the particle.

Parameters

particle

ParticleType

Particle to initialize.

Returns

void

Implementation of

InitBehavior.init

---

reset()

protected reset(): void;

Reset the behavior to its default state.

Returns

void

Implementation of

UpdateBehavior.reset

Overrides

EmitterBehavior.reset

---

update()

update(particle, deltaTime): void;

Updates the particle.

Parameters

particle

ParticleType

Particle to update.

deltaTime

number

Time elapsed since the last update, in seconds.

Returns

void

Implementation of

UpdateBehavior.update