@threlte/xr/dist/lib/toggleXRSession.js

Tools to more easily create VR and AR experiences with Threlte

import { lastSessionRequest, referenceSpaceType, session, xr } from '../internal/state.svelte.js';
import { getXRSessionOptions } from './getXRSessionOptions.js';
let pending;
/**
 * Starts / ends an XR session.
 *
 * @param sessionMode an XR session mode: 'inline' | 'immersive-vr' | 'immersive-ar'
 * @param sessionInit an XRSessionInit object
 * @param force Whether this button should only enter / exit an `XRSession`. Default is to toggle both ways
 * @returns
 */
export const toggleXRSession = (sessionMode, sessionInit, force) => {
    if (pending !== undefined)
        return pending;
    pending = run(sessionMode, sessionInit, force).finally(() => {
        pending = undefined;
    });
    return pending;
};
const run = async (sessionMode, sessionInit, force) => {
    const currentSession = session.current;
    const hasSession = currentSession !== undefined;
    if (force === 'enter' && hasSession)
        return currentSession;
    if (force === 'exit' && !hasSession)
        return;
    // Exit a session if entered. `session.current` is cleared by XR.svelte's
    // `handleSessionEnd` when the 'end' event fires — don't duplicate that here.
    if (hasSession) {
        await currentSession.end();
        return;
    }
    const manager = xr.current;
    if (manager === undefined) {
        throw new Error('An <XR> component was not created when attempting to toggle a session.');
    }
    // Otherwise enter a session
    const options = getXRSessionOptions(referenceSpaceType.current, sessionInit);
    const nextSession = await navigator.xr?.requestSession(sessionMode, options);
    if (nextSession === undefined) {
        throw new Error('A session was not able to be created.');
    }
    await manager.setSession(nextSession);
    lastSessionRequest.mode = sessionMode;
    lastSessionRequest.sessionInit = sessionInit;
    session.current = nextSession;
    return nextSession;
};