esengine/thirdparty/rapier.js/testbed2d/src/demos/lockedRotations.ts

import type {Testbed} from "../Testbed";

type RAPIER_API = typeof import("@dimforge/rapier2d");

export function initWorld(RAPIER: RAPIER_API, testbed: Testbed) {
    let gravity = new RAPIER.Vector2(0.0, -9.81);
    let world = new RAPIER.World(gravity);

    /*
     * The ground
     */
    let ground_size = 1.8;
    let ground_height = 1.0;

    let bodyDesc = RAPIER.RigidBodyDesc.fixed().setTranslation(
        0.0,
        -ground_height,
    );
    let body = world.createRigidBody(bodyDesc);
    let colliderDesc = RAPIER.ColliderDesc.cuboid(ground_size, ground_height);
    world.createCollider(colliderDesc, body);

    /*
     * A rectangle that only rotates along the `x` axis.
     */
    bodyDesc = RAPIER.RigidBodyDesc.dynamic()
        .setTranslation(0.0, 3.0)
        .lockTranslations();
    body = world.createRigidBody(bodyDesc);
    colliderDesc = RAPIER.ColliderDesc.cuboid(2.0, 0.6);
    world.createCollider(colliderDesc, body);

    /*
     * A cuboid that cannot rotate.
     */
    bodyDesc = RAPIER.RigidBodyDesc.dynamic()
        .setTranslation(0.4, 5.0)
        .lockRotations();
    body = world.createRigidBody(bodyDesc);
    colliderDesc = RAPIER.ColliderDesc.cuboid(0.4, 0.6);
    world.createCollider(colliderDesc, body);

    /*
     * Setup the testbed.
     */
    testbed.setWorld(world);
    testbed.lookAt({
        target: {x: 0.0, y: -2.0},
        zoom: 50.0,
    });
}