### KinematicCharacterController Set Up Direction Examples

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/controllers.md

Illustrates setting the 'up' direction for the KinematicCharacterController, showing examples for standard downward gravity and a custom gravity vector.

```typescript
// Standard gravity pointing down
controller.setUp({x: 0, y: 1});
```

```typescript
// Custom gravity direction
controller.setUp({x: 0, y: 0, z: 1});
```

--------------------------------

### Utility Functions

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/overview.md

Provides examples of utility functions available in the Rapier library, such as getting the library version and pre-allocating WASM memory.

```typescript
RAPIER.version()          // Get library version
RAPIER.reserveMemory(n)   // Pre-allocate WASM memory
```

--------------------------------

### Example: Processing Contact Manifold Data

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

An example demonstrating how to use the `contactPair` method to retrieve and log contact normal and the number of contacts from a manifold.

```typescript
world.narrowPhase.contactPair(h1, h2, (manifold, flipped) => {
  console.log('Contact normal:', manifold.contactNormal());
  console.log('Num contacts:', manifold.numContacts());
});
```

--------------------------------

### InteractionGroups Example

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/types.md

Example of creating an InteractionGroups mask where Group 1 (member) collides with groups 2 and 3.

```typescript
// Group 1 (member) collides with groups 2 and 3
const groups = (1 << 0) | (0b110 << 16);
```

--------------------------------

### Physics Simulation Setup

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/overview.md

Initializes the physics world, creates bodies and colliders, and sets up an event queue for collision and intersection events.

```typescript
const world = new World({x: 0, y: -9.81});

// Create bodies and colliders
const body = world.createRigidBody(RigidBodyDesc.dynamic());
const collider = world.createCollider(ColliderDesc.ball(0.5), body);

// Add events and joints
const eventQueue = new EventQueue(true, true);
```

--------------------------------

### JointAxesMask Example

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/joints.md

Example demonstrating how to use JointAxesMask to define free translation axes in X and Y for a generic joint.

```typescript
// Free to translate in X and Y, locked otherwise
const mask = JointAxesMask.LinX | JointAxesMask.LinY;
```

--------------------------------

### density()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Gets the density of the collider.

```APIDOC
## density()

### Description
Gets the density.

### Method
```typescript
density(): number
```

### Returns
- number - Density value
```

--------------------------------

### Example: Configure and Add a Vehicle Wheel

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/controllers.md

Demonstrates how to create and configure a WheelColliderDesc object with custom properties and then add it to a vehicle. This sets up a new wheel with specific physical characteristics.

```typescript
const wheelConfig = new WheelColliderDesc();
wheelConfig.chassisLocalPos = {x: 1, y: -1, z: 0};
wheelConfig.wheelRadius = 0.4;
wheelConfig.engineForce = 500;

const wheelIndex = vehicle.addWheel(wheelConfig);
```

--------------------------------

### Initialize Rapier World

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/overview.md

Imports the Rapier library and initializes a new physics world with a specified gravity vector. This is a common starting point for using the physics engine.

```typescript
import * as RAPIER from '@dimforge/rapier3d';

const world = new RAPIER.World({x: 0, y: -9.81, z: 0});
```

--------------------------------

### KinematicCharacterController Example Usage

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/controllers.md

Demonstrates how to use the `move` method of the KinematicCharacterController to handle player input and apply gravity, including checking for ground contact and logging collision information.

```typescript
const movement = {x: 0, y: 0, z: 0};
movement.x = input.right ? 5 : (input.left ? -5 : 0);
movement.y = controller.isGrounded() ? 0 : movement.y - 9.81 * dt;

const collision = controller.move(characterCollider, movement, world);
if (collision) {
  console.log('Hit something at distance:', collision.toi);
}
```

--------------------------------

### friction()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Gets the friction coefficient of the collider.

```APIDOC
## friction()

### Description
Gets the friction coefficient.

### Method
```typescript
friction(): number
```

### Returns
- number - Friction coefficient (0-1)
```

--------------------------------

### translation()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Gets the world-space position of the collider.

```APIDOC
## translation()

### Description
Gets the world-space position.

### Method
```typescript
translation(target?: Vector): Vector
```

### Parameters
#### Path Parameters
- **target** (Vector) - Optional - Object to populate

### Returns
- Vector - World position
```

--------------------------------

### solverGroups()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Gets the solver groups, determining which pairs generate contact forces.

```APIDOC
## solverGroups()

### Description
Gets the solver groups (which pairs generate contact forces).

### Method
```typescript
solverGroups(): InteractionGroups
```

### Returns
- InteractionGroups - A bit mask representing the solver groups.
```

--------------------------------

### Named Imports Example (TypeScript)

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/initialization.md

Shows how to import specific components from Rapier.js using named imports in TypeScript. This allows for cleaner code by only importing the necessary modules.

```typescript
import {
  World,
  RigidBody,
  RigidBodyDesc,
  Collider,
  ColliderDesc,
  Vector3,
  EventQueue
} from '@dimforge/rapier3d';

const world = new World({x: 0, y: -9.81, z: 0});
```

--------------------------------

### Example: Select PID Controller Axes

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/controllers.md

Shows how to combine PidAxesMask flags to specify that a PID controller should only manage the vertical position (LinY) and Z-axis rotation (AngZ).

```typescript
// Only control vertical position and rotation
const axes = PidAxesMask.LinY | PidAxesMask.AngZ;
```

--------------------------------

### Set World Gravity with 2D Vector

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/configuration.md

Example of setting world gravity using a 2D vector, suitable for 2D physics simulations.

```typescript
const world = new World({x: 0, y: -9.81});
// All dynamic bodies experience this acceleration
```

--------------------------------

### mass()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/rigid-body.md

Gets the mass of the rigid body in kilograms. A mass of 0 indicates infinite mass.

```APIDOC
## mass()

### Description
Gets the mass in kilograms (0 = infinite).

### Method
GET (conceptual)

### Response
#### Success Response
- **number** - Mass
```

--------------------------------

### Retrieving Rapier Version

Source: https://github.com/dimforge/rapier.js/blob/master/CHANGELOG.md

Get the version of the Rapier package as a string using the RAPIER.version() function.

```javascript
RAPIER.version()
```

--------------------------------

### Handle Character Collision Events

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/controllers.md

Example of how to handle collision events for a character controller. This snippet shows how to log information when a character hits another collider.

```typescript
controller.move(characterCollider, movement, world);

eventQueue.drainCollisionEvents((h1, h2, started) => {
  if (started && h1 === characterCollider.handle) {
    console.log('Character hit', h2);
  }
});
```

--------------------------------

### Initialize Rapier.js World and Simulation

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/initialization.md

This snippet demonstrates the essential steps for initializing a Rapier.js physics world, including optional memory pre-allocation, creating the world, setting up an event queue, defining bodies and colliders, running the simulation loop, and cleaning up resources.

```typescript
import * as RAPIER from '@dimforge/rapier3d';

// 1. Pre-allocate memory (optional)
RAPIER.reserveMemory(10 * 1024 * 1024);

// 2. Create world
const world = new RAPIER.World({x: 0, y: -9.81, z: 0});

// 3. Create event queue
const eventQueue = new RAPIER.EventQueue(true, true);

// 4. Create bodies and colliders
const bodyDesc = RAPIER.RigidBodyDesc.dynamic();
const body = world.createRigidBody(bodyDesc);

const colliderDesc = RAPIER.ColliderDesc.ball(0.5);
const collider = world.createCollider(colliderDesc, body);

// 5. Run simulation loop
let time = 0;
while (time < 100) {
  world.step(eventQueue);
  time += world.integrationParameters.dt;
}

// 6. Clean up
world.free();
```

--------------------------------

### Build Rapier.js Packages Manually

Source: https://github.com/dimforge/rapier.js/blob/master/README.md

Run these shell scripts from the repository root to build the Rapier.js packages. The prepare script only needs to be run once unless build preparation files are modified.

```shell
./builds/prepare_builds/prepare_all_projects.sh
./builds/prepare_builds/build_all_projects.sh
```

--------------------------------

### Using EventQueue for Physics Events

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/event-queue.md

Demonstrates how to create an EventQueue and process collision, sensor, and force events after each simulation step. Ensure the EventQueue is initialized with the desired event types enabled.

```typescript
const eventQueue = new EventQueue(true, true, true);

world.step(eventQueue);

// Process collision events
eventQueue.drainCollisionEvents((h1, h2, started) => {
  if (started) {
    console.log('Bodies collided:', h1, h2);
  }
});

// Process sensor events
eventQueue.drainIntersectionEvents((h1, h2, intersecting) => {
  if (intersecting) {
    console.log('Sensor activation:', h1, h2);
  }
});

// Process force events
eventQueue.drainContactForceEvents((event) => {
  const force = Math.sqrt(
    event.total_force.x ** 2 + 
    event.total_force.y ** 2
  );
  if (force > 100) {
    console.log('High impact detected');
  }
});
```

--------------------------------

### RigidBodyDesc Constructor

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/rigid-body.md

Creates a new rigid body descriptor with the specified body type. This is the starting point for configuring a new rigid body.

```APIDOC
## RigidBodyDesc Constructor

**Description:** Creates a new rigid body descriptor with the specified body type. This is the starting point for configuring a new rigid body.

**Parameters:**
- **status** (RigidBodyType) - Required - The type of rigid body to create.

**TypeScript Definition:**
```typescript
constructor(status: RigidBodyType)
```
```

--------------------------------

### body2

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/joints.md

Gets the child body of a MultibodyJoint.

```APIDOC
## body2()

### Description
Gets the child body.

### Method
```typescript
body2(): RigidBody
```

### Returns
- RigidBody
```

--------------------------------

### Create 3D Rotation (Quaternion)

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/types.md

Shows how to create quaternion instances for 3D rotations using RotationOps, class constructors, or plain objects.

```typescript
// Using RotationOps
const identity = RotationOps.identity(); // {x: 0, y: 0, z: 0, w: 1}

// Using class constructor
const q = new Quaternion(0, 0, 0, 1);

// Using plain objects
const q2 = {x: 0, y: 0, z: 0, w: 1};
```

--------------------------------

### Create and Move a Character Controller

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/overview.md

Initialize a character controller with a sliding speed and set its up direction. Then, use the `move` method to apply movement and handle collisions.

```typescript
const controller = world.createCharacterController(0.01);
controller.setUp({x: 0, y: 1});

const collision = controller.move(charCollider, movement, world);
```

--------------------------------

### body1

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/joints.md

Gets the parent body of a MultibodyJoint.

```APIDOC
## body1()

### Description
Gets the parent body.

### Method
```typescript
body1(): RigidBody
```

### Returns
- RigidBody
```

--------------------------------

### restitution()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Gets the restitution (bounciness) of the collider.

```APIDOC
## restitution()

### Description
Gets the restitution (bounciness).

### Method
```typescript
restitution(): number
```

### Returns
- number - Restitution value (0-1)
```

--------------------------------

### Initialize Rapier.js World

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/README.md

Pre-allocates memory and creates a new physics world with a specified gravity vector. This is the first step in using the physics engine.

```typescript
import * as RAPIER from '@dimforge/rapier3d';

RAPIER.reserveMemory(10 * 1024 * 1024); // Optional: pre-allocate
const world = new RAPIER.World({x: 0, y: -9.81, z: 0});
```

--------------------------------

### mass()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Gets the mass contributed by this collider.

```APIDOC
## mass()

### Description
Gets the mass contributed by this collider.

### Method
```typescript
mass(): number
```

### Returns
- number - Mass in kilograms
```

--------------------------------

### NarrowPhase.free()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Releases the WASM resources associated with the NarrowPhase.

```APIDOC
## NarrowPhase.free()

### Description
Releases WASM resources.

### Method
```typescript
free(): void
```
```

--------------------------------

### rotation()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Gets the world-space orientation of the collider.

```APIDOC
## rotation()

### Description
Gets the world-space orientation.

### Method
```typescript
rotation(target?: Rotation): Rotation
```

### Returns
- Rotation - World orientation
```

--------------------------------

### CCDSolver.free()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Releases the WASM resources associated with the CCDSolver.

```APIDOC
## CCDSolver.free()

### Description
Releases WASM resources.

### Method
```typescript
free(): void
```
```

--------------------------------

### Create 3D Vector

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/types.md

Demonstrates various ways to create a 3D vector instance using VectorOps, class constructors, or plain objects.

```typescript
// Using VectorOps
const v = VectorOps.new(1, 2, 3);

// Using class constructors
const v2 = new Vector3(1, 2, 3);

// Using plain objects
const v3 = {x: 1, y: 2, z: 3};
```

--------------------------------

### volumeContactForces()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Gets the total contact force at this frame.

```APIDOC
## volumeContactForces()

### Description
Gets the total contact force at this frame.

### Method
N/A (This is a getter method)

### Returns
- **number**: Force magnitude
```

--------------------------------

### createCharacterController()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/world.md

Creates a character controller for kinematic body movement within the physics world.

```APIDOC
## createCharacterController()

### Description
Creates a character controller for kinematic body movement.

### Method
`createCharacterController`

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Parameters
- **offset** (number) - Required - Padding distance between character and obstacles

### Response
#### Success Response (KinematicCharacterController)
KinematicCharacterController

### Example
```typescript
const controller = world.createCharacterController(0.01);
controller.setOffset(0.01);
```
```

--------------------------------

### gravityScale()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/rigid-body.md

Gets the gravity scale multiplier for the rigid body.

```APIDOC
## gravityScale()

### Description
Gets the gravity scale multiplier.

### Method
GET (conceptual)

### Response
#### Success Response
- **number** - Gravity scale
```

--------------------------------

### Configure PID Controller for Position and Velocity Targets

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/configuration.md

Initialize a PID controller and set target position, rotation, linear velocity, and angular velocity.

```typescript
const controller = new PidController();

// Position target
controller.setTargetPos({x: 0, y: 5});
controller.setTargetRot(0); // 2D angle or Quaternion (3D)

// Velocity target
controller.setTargetVel({x: 0, y: 0});
controller.setTargetAngvel(0);
```

--------------------------------

### parent()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Gets the parent rigid body if the collider is attached.

```APIDOC
## parent()

### Description
Gets the parent rigid body if attached.

### Method
```typescript
parent(): RigidBody | null
```

### Returns
- RigidBody | null - The parent rigid body or null if not attached.
```

--------------------------------

### numColliders()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/rigid-body.md

Gets the total number of colliders attached to this rigid body.

```APIDOC
## numColliders()

### Description
Gets the number of attached colliders.

### Method
```typescript
numColliders(): number
```

### Response
#### Success Response (200)
- **return value** (number) - The count of attached colliders.
```

--------------------------------

### BroadPhase.free()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Releases the WASM resources associated with the BroadPhase.

```APIDOC
## BroadPhase.free()

### Description
Releases WASM resources.

### Method
```typescript
free(): void
```
```

--------------------------------

### serialize()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/world.md

Serializes the current state of the physics world into a binary format.

```APIDOC
## serialize()

### Description
Serializes the world state to binary format.

### Method
`serialize`

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Response
#### Success Response (Uint8Array)
Uint8Array - Binary representation of the world

### Example
```typescript
const binary = world.serialize();
// Save to file or send over network
```
```

--------------------------------

### PrismaticImpulseJoint.translation()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/joints.md

Gets the current translation along the prismatic axis for a PrismaticImpulseJoint.

```APIDOC
## PrismaticImpulseJoint.translation()

### Description
Gets the current translation along the prismatic axis.

### Method
`translation(): number`

### Returns
- **number**: The current translation along the prismatic axis.
```

--------------------------------

### RigidBodyDesc Static Methods

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/rigid-body.md

Factory methods for creating `RigidBodyDesc` instances for different body types.

```APIDOC
## RigidBodyDesc Static Methods

**Description:** Factory methods for creating `RigidBodyDesc` instances for different body types.

### `dynamic()`
Creates a descriptor for a dynamic rigid body.

**Returns:** `RigidBodyDesc`

**Example:**
```typescript
const desc = RigidBodyDesc.dynamic()
  .setTranslation({x: 0, y: 5})
  .setLinvel({x: 1, y: 0});
```

### `fixed()`
Creates a descriptor for a fixed (immovable) rigid body.

**Returns:** `RigidBodyDesc`

### `kinematicPositionBased()`
Creates a descriptor for a position-based kinematic body.

**Returns:** `RigidBodyDesc`

### `kinematicVelocityBased()`
Creates a descriptor for a velocity-based kinematic body.

**Returns:** `RigidBodyDesc`
```

--------------------------------

### collisionGroups()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Gets the collision groups, determining which groups can collide with this collider.

```APIDOC
## collisionGroups()

### Description
Gets the collision groups (which groups can collide with this).

### Method
```typescript
collisionGroups(): InteractionGroups
```

### Returns
- InteractionGroups - A bit mask representing the collision groups.
```

--------------------------------

### MultibodyJointSet.len()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Gets the total number of multibody joints currently managed.

```APIDOC
## MultibodyJointSet.len()

### Description
Gets the number of multibody joints.

### Method
```typescript
len(): number
```

### Returns
number - Joint count
```

--------------------------------

### numWheels()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/controllers.md

Gets the total number of wheels currently configured for the vehicle controller.

```APIDOC
## numWheels()

### Description
Gets the number of wheels.

### Method
```typescript
numWheels(): number
```

### Returns
number
```

--------------------------------

### Simulate a Simple Falling Body

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/overview.md

Create a dynamic rigid body and a collider, then step the physics world simulation over time. Log the body's translation after each step and free the world resources when done.

```typescript
const world = new World({x: 0, y: -9.81});

const body = world.createRigidBody(RigidBodyDesc.dynamic());
const collider = world.createCollider(ColliderDesc.ball(0.5), body);

for (let i = 0; i < 100; i++) {
  world.step();
  console.log(body.translation());
}

world.free();
```

--------------------------------

### World Constructor

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/world.md

Creates a new physics world with the specified gravity vector. This is the primary way to initialize a physics simulation.

```APIDOC
## World Constructor

### Description
Creates a new physics world with the specified gravity vector.

### Parameters
#### Path Parameters
- **gravity** (Vector) - Yes - The gravity acceleration vector applied to all dynamic bodies
```

--------------------------------

### Get Collider Count

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Returns the total number of colliders managed by the set.

```typescript
world.colliders.len()
```

--------------------------------

### step()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/world.md

Advances the physics simulation by one timestep. This method should be called repeatedly to update the physics state. It can optionally accept an event queue and physics hooks.

```APIDOC
## step()

### Description
Advances the physics simulation by one timestep.

### Method
```typescript
step(eventQueue?: EventQueue, hooks?: PhysicsHooks): void
```

### Parameters
#### Query Parameters
- **eventQueue** (EventQueue) - No - Queue to collect contact and intersection events
- **hooks** (PhysicsHooks) - No - Hooks to filter collisions and intersections

### Example
```typescript
const world = new World({x: 0, y: -9.81});
const eventQueue = new EventQueue(true, true);

// Simulate
world.step(eventQueue);

// Process events
eventQueue.drainCollisionEvents((handle1, handle2, started) => {
  console.log('Collision between', handle1, handle2);
});
```
```

--------------------------------

### Importing Rapier.js

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/initialization.md

Import the Rapier.js library for either 3D or 2D physics. All public API functions and classes are available directly on the imported RAPIER object.

```APIDOC
## Importing Rapier.js

### Description
Import the Rapier.js library for either 3D or 2D physics. All public API functions and classes are available directly on the imported RAPIER object.

### Usage

```typescript
// For 3D physics
import * as RAPIER from '@dimforge/rapier3d';

// For 2D physics
import * as RAPIER from '@dimforge/rapier2d';
```
```

--------------------------------

### RevoluteImpulseJoint.angle()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/joints.md

Gets the current rotation angle in radians for a RevoluteImpulseJoint. This method is specific to 2D physics.

```APIDOC
## RevoluteImpulseJoint.angle() (2D only)

### Description
Gets the current rotation angle in radians.

### Method
`angle(): number`

### Returns
- **number**: The current rotation angle in radians.
```

--------------------------------

### Create a new physics world

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/world.md

Initializes a new physics world with a specified gravity vector. This is the primary entry point for any physics simulation.

```typescript
constructor(gravity: Vector)
```

--------------------------------

### Get Joint Type

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/joints.md

Returns the type of the ImpulseJoint. This can be used to differentiate between various joint configurations.

```typescript
type(): JointType
```

--------------------------------

### Import Rapier.js Module

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/initialization.md

Import the main rapier.js module for 3D or 2D physics simulations. All public API functions and classes are available directly on the imported RAPIER object.

```typescript
import * as RAPIER from '@dimforge/rapier3d';
// or for 2D:
import * as RAPIER from '@dimforge/rapier2d';
```

--------------------------------

### Get Rigid Body Gravity Scale

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/rigid-body.md

Retrieves the gravity scale multiplier for the rigid body.

```typescript
gravityScale(): number
```

--------------------------------

### Get Number of Wheels in Vehicle Controller

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/controllers.md

Retrieves the current number of wheels attached to the DynamicRayCastVehicleController.

```typescript
numWheels(): number
```

--------------------------------

### IslandManager.free()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Releases the WASM resources associated with the IslandManager.

```APIDOC
## IslandManager.free()

### Description
Releases WASM resources.

### Method
```typescript
free(): void
```
```

--------------------------------

### version()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/initialization.md

Retrieves the semantic version string of the rapier.js library.

```APIDOC
## version()

### Description
Returns the semantic version of the rapier.js library.

### Method
```typescript
function version(): string
```

### Returns
- string: Version string (e.g., "0.20.0")

### Example
```typescript
console.log('Rapier version:', RAPIER.version());
```
```

--------------------------------

### Get Impulse Joint Count

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Returns the total number of impulse joints managed by the set.

```typescript
world.impulseJoints.len()
```

--------------------------------

### Get Rigid Body Count

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Returns the total number of rigid bodies managed by the set.

```typescript
world.bodies.len()
```

--------------------------------

### Configure KinematicCharacterController

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/configuration.md

Set up a character controller with specific parameters like up direction, impulse application to dynamic bodies, and custom mass.

```typescript
const controller = world.createCharacterController(0.01);
controller.setUp({x: 0, y: 1});
controller.setApplyImpulsesToDynamicBodies(true);
controller.setCharacterMass(80);
```

--------------------------------

### Create a Character Controller

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/world.md

Initializes a character controller for kinematic body movement. The `offset` parameter defines the padding distance between the character and obstacles.

```typescript
const controller = world.createCharacterController(0.01);
controller.setOffset(0.01);
```

--------------------------------

### Get Collider by Handle

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Retrieves a collider using its unique handle. Returns null if the collider has been deleted.

```typescript
const collider = world.colliders.get(colliderHandle);
if (collider) {
  console.log(collider.translation());
}
```

--------------------------------

### Get Number of Colliders

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/rigid-body.md

Retrieves the total number of colliders attached to this rigid body. This can be used to iterate through all colliders.

```typescript
numColliders(): number
```

--------------------------------

### Full Physics Simulation Loop

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/README.md

A comprehensive physics loop demonstrating applying forces, updating kinematic bodies, stepping the simulation, processing collision events, and reading transforms for rendering. Ensure to free world resources after the loop.

```typescript
const world = new RAPIER.World(gravity);
const eventQueue = new RAPIER.EventQueue(true, true);

// Add bodies and colliders
// ...

// Simulation loop
for (let frame = 0; frame < maxFrames; frame++) {
  // Apply forces
  body.applyForce(forceVector);
  
  // Update kinematic bodies
  kinematicBody.setTranslation(newPos, true);
  
  // Step physics
  world.step(eventQueue);
  
  // Process events
  eventQueue.drainCollisionEvents((h1, h2, started) => {
    // Handle collisions
  });
  
  // Read transforms for rendering
  const pos = body.translation();
  const rot = body.rotation();
  // Update graphics...
}

world.free();
```

--------------------------------

### Get Second Attached Rigid Body

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/joints.md

Retrieves the second rigid body connected to the ImpulseJoint. This is a read-only property.

```typescript
body2(): RigidBody
```

--------------------------------

### IntegrationParameters

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/initialization.md

Defines simulation parameters such as time step and solver iterations. It can be initialized with raw parameters.

```APIDOC
## Class: IntegrationParameters

### Description
Simulation parameters that control the physics simulation's behavior, including the time step (`dt`) and the number of solver iterations.

### Constructor
- `constructor(raw?: RawIntegrationParameters)`: Initializes a new instance of `IntegrationParameters`. The `raw` parameter is an optional object containing initial values for the parameters.

### Properties
- **dt** (number): The time step for the simulation. Determines the granularity of physics updates.
- **numSolverIterations** (number): The number of iterations the physics solver will perform to resolve constraints. More iterations lead to higher accuracy but also increased computation time.

### Related
See `Configuration` documentation for more details.
```

--------------------------------

### Get First Attached Rigid Body

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/joints.md

Retrieves the first rigid body connected to the ImpulseJoint. This is a read-only property.

```typescript
body1(): RigidBody
```

--------------------------------

### Get Collider Restitution

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Retrieve the restitution (bounciness) of a collider using the `restitution()` method. The value is between 0 and 1.

```typescript
restitution(): number
```

--------------------------------

### Initialize World with Gravity

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/configuration.md

Configure the world's gravity during initialization. The gravity is a vector property on the World instance.

```typescript
const world = new World({x: 0, y: -9.81, z: 0});
```

--------------------------------

### Create a Zero Vector

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/math.md

Creates a vector with all components initialized to zero. Useful for starting points or reset states.

```typescript
const v = VectorOps.zeros(); // {x: 0, y: 0} or {x: 0, y: 0, z: 0}
```

--------------------------------

### Get Rapier.js Version

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/initialization.md

Retrieve the semantic version of the currently used rapier.js library. This is useful for compatibility checks or logging.

```typescript
function version(): string
```

```typescript
console.log('Rapier version:', RAPIER.version());
```

--------------------------------

### createRigidBody()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/world.md

Creates a new rigid body in the world with the properties defined in the provided descriptor. Rigid bodies represent dynamic or static physical objects in the simulation.

```APIDOC
## createRigidBody()

### Description
Creates a new rigid body in the world.

### Method
```typescript
createRigidBody(desc: RigidBodyDesc): RigidBody
```

### Parameters
#### Path Parameters
- **desc** (RigidBodyDesc) - Yes - The rigid body descriptor with initial properties

### Returns
- **RigidBody** - The created rigid body

### Example
```typescript
const bodyDesc = RigidBodyDesc.dynamic()
  .setTranslation({x: 0, y: 10});
const body = world.createRigidBody(bodyDesc);
```
```

--------------------------------

### Get Collider Friction

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Obtain the friction coefficient of a collider using the `friction()` method. The value ranges from 0 to 1.

```typescript
friction(): number
```

--------------------------------

### World Class

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/initialization.md

The main physics simulation container. It manages the simulation steps, rigid body creation, and other physics-related operations.

```APIDOC
## World

### Description
Main physics simulation container.

### Class Definition
```typescript
class World {
  constructor(gravity: Vector)
  step(eventQueue?: EventQueue, hooks?: PhysicsHooks): void
  createRigidBody(desc: RigidBodyDesc): RigidBody
  // ... (see World documentation)
}
```

### Related
`api-reference/world.md`
```

--------------------------------

### Get Number of Multibody Joints

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Returns the total count of multibody joints currently managed. This is a simple numeric value.

```typescript
len(): number
```

--------------------------------

### RigidBodyDesc Methods

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/rigid-body.md

Methods for configuring the properties of a `RigidBodyDesc`.

```APIDOC
## RigidBodyDesc Methods

**Description:** Methods for configuring the properties of a `RigidBodyDesc`.

### `setTranslation(translation: Vector): RigidBodyDesc`
Sets the initial world position.

### `setRotation(rotation: Rotation): RigidBodyDesc`
Sets the initial world orientation.

### `setLinvel(linvel: Vector): RigidBodyDesc`
Sets the initial linear velocity.

### `setAngvel(angvel: number | Vector): RigidBodyDesc`
Sets the initial angular velocity.

### `setMass(mass: number): RigidBodyDesc`
Sets the mass in kilograms (0 for infinite mass).

### `setGravityScale(gravityScale: number): RigidBodyDesc`
Sets the gravity scale multiplier.

### `setLinearDamping(damping: number): RigidBodyDesc`
Sets linear damping (0-1, typically).

### `setAngularDamping(damping: number): RigidBodyDesc`
Sets angular damping (0-1, typically).

### `setCanSleep(can: boolean): RigidBodyDesc`
Sets whether the body can sleep.

### `setCcdEnabled(enabled: boolean): RigidBodyDesc`
Enables continuous collision detection.
```

--------------------------------

### Create DynamicRayCastVehicleController

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/controllers.md

Creates a new vehicle controller for a chassis rigid body using raycasts for suspension. This is for 3D environments only.

```typescript
constructor(chassisBody: RigidBody)
```

--------------------------------

### Get Multibody Joint by Handle

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Retrieves a multibody joint using its unique handle. Returns null if the joint has been deleted.

```typescript
get(handle: MultibodyJointHandle): MultibodyJoint | null
```

--------------------------------

### projectPoint()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Projects a point onto this collider to find the closest point on the surface.

```APIDOC
## projectPoint()

### Description
Projects a point onto this collider.

### Method
N/A (This is a method call)

### Parameters
- **point** (Vector) - Yes - Point to project
- **solid** (boolean) - Yes - If true, points inside are projected to surface

### Response
#### Success Response
- **PointColliderProjection | null**: The projection details or null if the point is outside the collider and not solid.
```

--------------------------------

### Get Impulse Joint by Handle

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Retrieves an impulse joint using its unique handle. Returns null if the joint has been deleted.

```typescript
world.impulseJoints.get(jointHandle)
```

--------------------------------

### Get Rigid Body by Handle

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Retrieves a rigid body using its unique handle. Returns null if the body has been deleted.

```typescript
const body = world.bodies.get(bodyHandle);
if (body) {
  console.log(body.translation());
}
```

--------------------------------

### Accessing and Modifying World and Body Properties

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/initialization.md

Demonstrates how to read and write properties for world integration parameters and body transformations. Some properties use getters/setters, while others allow direct access.

```typescript
// Reading
const dt = world.integrationParameters.dt;
const pos = body.translation();

// Writing
world.integrationParameters.dt = 1/120;
body.setTranslation({x: 0, y: 5}, true);
```

```typescript
// Direct access
world.gravity = {x: 0, y: -20};
const g = world.gravity;
```

--------------------------------

### free()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/queries.md

Releases WASM resources associated with the geometry.

```APIDOC
## free()

### Description
Releases WASM resources.

### Method
`void`

### Signature
```typescript
free(): void
```

### Source
`src.ts/geometry/broad_phase.ts`
```

--------------------------------

### Get Collider Density

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Retrieve the density of a collider using the `density()` method. Density is defined as mass per unit volume.

```typescript
density(): number
```

--------------------------------

### Get Collider Mass

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Determine the mass contributed by a collider by calling the `mass()` method. The returned value represents the mass in kilograms.

```typescript
mass(): number
```

--------------------------------

### Vector and Rotation Math Utilities

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/initialization.md

Provides classes for 2D and 3D vectors, quaternions, and operations for vector and rotation manipulation. Includes static methods for creating, initializing, and manipulating these math objects.

```typescript
class Vector2 { constructor(x: number, y: number) }
class Vector3 { constructor(x: number, y: number, z: number) }
class Quaternion { constructor(x, y, z, w: number) }

class VectorOps {
  static new(...): Vector
  static zeros(): Vector
  static fromBuffer(buffer: Float32Array, target?: Vector): Vector
  // ... (see Math documentation)
}

class RotationOps {
  static identity(): Rotation
  static fromBuffer(buffer: Float32Array, target?: Rotation): Rotation
  // ... (see Math documentation)
}
```

--------------------------------

### Get Collider Rotation

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Obtain the world-space orientation of a collider with the `rotation()` method. An optional `Rotation` object can be supplied to store the result.

```typescript
rotation(target?: Rotation): Rotation
```

--------------------------------

### wakeUp()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/rigid-body.md

Wakes the rigid body up, enabling its simulation. This is typically called when an external force or collision occurs.

```APIDOC
## wakeUp()

### Description
Wakes the body up (enables simulation).

### Method
```typescript
wakeUp(): void
```
```

--------------------------------

### Get KinematicCharacterController Up Direction

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/controllers.md

Retrieves the current 'up' direction vector used by the character controller for floor detection and gravity-relative operations.

```typescript
up(): Vector
```

--------------------------------

### Get KinematicCharacterController Offset

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/controllers.md

Retrieves the current padding distance set for the character controller. This value determines the gap between the character and obstacles.

```typescript
offset(): number
```

--------------------------------

### RigidBodySet.forEachBody()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Iterates over all rigid bodies (both active and sleeping) in the set, executing a callback function for each.

```APIDOC
## RigidBodySet.forEachBody()

### Description
Iterates through all bodies (active and sleeping).

### Method
forEachBody

### Parameters
#### Path Parameters
- **callback** (function) - Required - Called for each body
```

--------------------------------

### Perform a Raycast Query

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/README.md

Initializes a query pipeline and performs a raycast to detect intersections with colliders in the world. It logs the hit distance if an intersection occurs.

```typescript
const queryPipeline = new RAPIER.QueryPipeline();
const ray = new RAPIER.Ray({x: 0, y: 0, z: 0}, {x: 1, y: 0, z: 0});

const hit = queryPipeline.castRay(
  world.colliders,
  ray,
  1000,
  false,
  0xffffffff
);

if (hit) {
  console.log('Hit at distance:', hit.toi);
}
```

--------------------------------

### drainCollisionEvents

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/event-queue.md

Processes all queued collision events, invoking a callback for each event indicating whether a contact started or ended between two colliders.

```APIDOC
## drainCollisionEvents()

### Description
Processes all queued collision events (contact started/stopped).

### Method
```typescript
drainCollisionEvents(callback: (handle1: ColliderHandle, handle2: ColliderHandle, started: boolean) => void): void
```

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Parameters
- **callback** (function) - Required - Called for each collision event
  - **handle1** (ColliderHandle) - First collider identifier
  - **handle2** (ColliderHandle) - Second collider identifier
  - **started** (boolean) - true if contact started, false if ended

### Request Example
```typescript
const eventQueue = new EventQueue(true, false);
world.step(eventQueue);

eventQueue.drainCollisionEvents((h1, h2, started) => {
  if (started) {
    console.log('Collision started between', h1, h2);
  } else {
    console.log('Collision ended between', h1, h2);
  }
});
```

### Response
#### Success Response (200)
None

#### Response Example
None
```

--------------------------------

### Create a Friction Platform Collider

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/configuration.md

Use ColliderDesc.cuboid to create a platform with high friction. Set density to 0 for infinite mass.

```typescript
const platform = ColliderDesc.cuboid(10, 0.5, 10)
  .setFriction(2.0)
  .setDensity(0); // Infinite mass

const collider = world.createCollider(platform, groundBody);
```

--------------------------------

### Configure Dynamic Rigid Body

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/overview.md

Create a dynamic rigid body description, setting its mass, linear and angular damping, and enabling continuous collision detection (CCD) for more accurate collision handling.

```typescript
const desc = RigidBodyDesc.dynamic()
  .setMass(10)
  .setLinearDamping(0.1)
  .setAngularDamping(0.1)
  .setCcdEnabled(true); // Continuous collision detection
```

--------------------------------

### Get Total Contact Force

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Retrieves the total magnitude of contact forces acting on the collider at the current frame. This value is a scalar number.

```typescript
volumeContactForces(): number
```

--------------------------------

### reserveMemory()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/initialization.md

Pre-allocates additional WebAssembly linear memory to reduce future allocation overhead during initialization. This is an experimental feature.

```APIDOC
## reserveMemory()

### Description
Pre-allocates additional WebAssembly linear memory to reduce future allocation overhead. This is experimental and useful for applications with predictable memory requirements. Call once during initialization for best results.

### Method
```typescript
function reserveMemory(extraBytesCount: number): void
```

### Parameters
#### Path Parameters
- **extraBytesCount** (number) - Required - Number of extra bytes to reserve

### Notes
- This is experimental and the allocator may perform additional allocations regardless.
- Useful for applications with predictable memory requirements.
- Call once during initialization for best results.

### Example
```typescript
// Reserve 50MB of extra memory
RAPIER.reserveMemory(50 * 1024 * 1024);

const world = new RAPIER.World({x: 0, y: -9.81});
```
```

--------------------------------

### Get Rigid Body Angular Velocity

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/rigid-body.md

Retrieves the current angular velocity of the rigid body. Returns a number for 2D and a Vector for 3D.

```typescript
angvel(target?: Rotation | number): Rotation | number
```

--------------------------------

### Free physics world resources

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/world.md

Releases all WASM memory occupied by the physics world and its child structures. This should be called to clean up resources when the world is no longer needed.

```typescript
const world = new World({x: 0, y: -9.81});
// ... use world ...
world.free(); // Clean up resources
```

--------------------------------

### Set KinematicCharacterController Offset

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/controllers.md

Updates the padding distance for the character controller. This affects how close the character can get to obstacles before collision response is triggered.

```typescript
setOffset(offset: number): void
```

--------------------------------

### deserialize()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/world.md

Deserializes a physics world from a binary format. This is a static method.

```APIDOC
## deserialize()

### Description
Deserializes a world from binary format.

### Method
`static deserialize`

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Parameters
- **data** (Uint8Array) - Required - Binary world data

### Response
#### Success Response (World)
World - Reconstructed physics world

### Example
```typescript
const world = World.deserialize(binaryData);
```
```

--------------------------------

### Get Prismatic Joint Translation

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/joints.md

Retrieves the current translation along the prismatic axis of a prismatic joint. This indicates the joint's linear position.

```typescript
translation(): number
```

--------------------------------

### Vector3 Constructor

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/math.md

Creates a 3D vector with x, y, and z components.

```APIDOC
## Vector3 Constructor

### Description
Creates a 3D vector.

### Method
`constructor(x: number, y: number, z: number)`

### Parameters
#### Path Parameters
- **x** (number) - Required - The x component of the vector.
- **y** (number) - Required - The y component of the vector.
- **z** (number) - Required - The z component of the vector.

### Request Example
```typescript
const v = new Vector3(1, 2, 3);
console.log(v.x, v.y, v.z); // 1 2 3
```
```

--------------------------------

### translation()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/rigid-body.md

Gets the world-space position of the rigid body. An optional target object can be provided to populate with the position, otherwise a new Vector is created and returned.

```APIDOC
## translation()

### Description
Gets the world-space position.

### Method
GET (conceptual)

### Parameters
#### Query Parameters
- **target** (Vector) - Optional - Object to populate (creates new if omitted)

### Response
#### Success Response
- **Vector** - World position

### Response Example
{
  "example": "Vector { x: number, y: number }"
}

### Example:
```typescript
const pos = body.translation();
console.log(pos.x, pos.y);
```
```

--------------------------------

### Get Collider Translation

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/collider.md

Retrieve the world-space position of a collider using the `translation()` method. An optional `Vector` object can be provided to populate with the position data.

```typescript
translation(target?: Vector): Vector
```

--------------------------------

### KinematicCharacterController Constructor

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/controllers.md

Creates a new character controller instance. Use this to initialize a controller for player characters.

```typescript
constructor(offset: number)
```

--------------------------------

### Get KinematicCharacterController Custom Mass

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/controllers.md

Retrieves the custom mass value used for impulse resolution. Returns the set mass or null if auto-detection is active.

```typescript
characterMass(): number | null
```

--------------------------------

### RigidBodyDesc Static Methods and Properties

Source: https://github.com/dimforge/rapier.js/blob/master/CHANGELOG.md

Use new static methods like RigidBodyDesc.newStatic, .newDynamic, and .newKinematic for creating rigid bodies. Access and set gravity scale, linear damping, and angular damping.

```javascript
RigidBodyDesc.newStatic()
RigidBodyDesc.newDynamic()
RigidBodyDesc.newKinematic()
RigidBodyDesc.setGravityScale(scale)
RigidBody.gravityScale
RigidBody.setGravityScale(scale)
RigidBody.setLinearDamping(damping)
RigidBody.setAngularDamping(damping)
```

--------------------------------

### Get Specific Collider by Index

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/rigid-body.md

Retrieves a specific collider attached to the rigid body by its index. The index must be within the valid range of [0, numColliders()).

```typescript
collider(index: number): Collider
```

--------------------------------

### RigidBodySet.forEachActiveBody()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/sets.md

Iterates over all active (non-sleeping) rigid bodies in the set, executing a callback function for each.

```APIDOC
## RigidBodySet.forEachActiveBody()

### Description
Iterates through all non-sleeping bodies.

### Method
forEachActiveBody

### Parameters
#### Path Parameters
- **callback** (function) - Required - Called for each active body
```

--------------------------------

### Rapier.js File Organization

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/README.md

This snippet shows the directory structure for the Rapier.js project, outlining the location of the main README, configuration files, type definitions, and API reference modules.

```tree
output/
├── README.md (this file)
├── overview.md
├── types.md
├── configuration.md
└── api-reference/
    ├── initialization.md
    ├── world.md
    ├── rigid-body.md
    ├── collider.md
    ├── shapes.md
    ├── joints.md
    ├── event-queue.md
    ├── queries.md
    ├── controllers.md
    ├── sets.md
    └── math.md
```

--------------------------------

### Get Revolute Joint Angle (2D)

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/joints.md

Retrieves the current rotation angle in radians for a revolute joint in a 2D physics simulation. This method is specific to 2D.

```typescript
angle(): number
```

--------------------------------

### Create PID Controller

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/controllers.md

Creates a new PID (Proportional-Integral-Derivative) controller instance. This controller is used for smooth body dynamics.

```typescript
constructor()
```

--------------------------------

### rotation()

Source: https://github.com/dimforge/rapier.js/blob/master/_autodocs/api-reference/rigid-body.md

Gets the world-space orientation of the rigid body. An optional target object can be provided to populate with the orientation, otherwise a new Rotation object is created and returned.

```APIDOC
## rotation()

### Description
Gets the world-space orientation.

### Method
GET (conceptual)

### Parameters
#### Query Parameters
- **target** (Rotation) - Optional - Object to populate

### Response
#### Success Response
- **Rotation** - World orientation

### Response Example
{
  "example": "Rotation { x: number, y: number, z: number, w: number }"
}
```