RigidBody

The RigidBody component enables physics movement for an entity, making it move under velocity, acceleration, and gravity. It works together with a collider on the same entity. See Physics for an overview.

Body types

Type	Description
`RigidBodyType.Dynamic`	Affected by gravity and velocity, and moved by collisions with other bodies. For objects that need full physical behavior.
`RigidBodyType.Kinematic`	Moved by applied velocity, but unaffected by gravity or collisions from other bodies. For moving platforms or scripted movement.
`RigidBodyType.Static`	Immobile. Unaffected by velocity or gravity. For walls and level geometry.

Options

Option	Type	Default	Description
`type`	`RigidBodyType`	`Dynamic`	The body type.
`velocity`	`Vector2`	`(0, 0)`	Velocity in pixels per second. For Dynamic and Kinematic bodies.
`acceleration`	`Vector2`	`(0, 0)`	Acceleration in pixels per second squared. For Dynamic and Kinematic bodies.
`gravity`	`number`	`0`	Gravity in pixels per second squared. For Dynamic bodies only.
`staticForLayers`	`string[]`	`[]`	Collision layers for which this body behaves as static (see below).

Static for layers

When two Dynamic bodies collide, both are repositioned by half the penetration. When a Dynamic body collides with a Static one, only the Dynamic body is repositioned.

staticForLayers lets a Dynamic body behave as static toward specific layers. When a Dynamic body whose collider layer is listed in staticForLayers collides with this body, only the other body is repositioned — this one stays in place, as if it were static. For every other collision, the body still behaves as its own type.

For example, a moving platform that should push the player but never be pushed back can list the player’s collision layer:

new RigidBody({ type: RigidBodyType.Dynamic, staticForLayers: ["Player"] });

Example

import { Transform, BoxCollider, RigidBody, RigidBodyType } from "angry-pixel";

this.entityManager.createEntity([
    new Transform(),
    new BoxCollider({ width: 16, height: 16, layer: "Player" }),
    new RigidBody({ type: RigidBodyType.Dynamic, gravity: 1000 }),
]);