@threlte/xr/dist/hooks/useHandJoint.js

Tools to more easily create VR and AR experiences with Threlte

import { currentWritable, useTask, useThrelte } from '@threlte/core';
import { useHand } from './useHand';
/**
 * Provides a reference to a requested hand joint, once available.
 */
export const useHandJoint = (handedness, joint) => {
    const { invalidate } = useThrelte();
    const jointSpaceStore = currentWritable(undefined);
    const xrhand = useHand(handedness);
    const { stop } = useTask(() => {
        const jointSpace = xrhand.current?.hand.joints[joint];
        // The joint radius is a good indicator that the joint is ready
        if (jointSpace?.jointRadius !== undefined) {
            jointSpaceStore.set(jointSpace);
            invalidate();
            stop();
        }
    }, { autoInvalidate: false });
    return jointSpaceStore;
};