@adhiban/three-mesh-ui/examples/hidden_overflow.js

a library on top of three.js to help in creating 3D user interfaces, with minor changes ;)

import * as THREE from 'three';
import { VRButton } from 'three/examples/jsm/webxr/VRButton.js';
import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls.js';
import { BoxLineGeometry } from 'three/examples/jsm/geometries/BoxLineGeometry.js';

import ThreeMeshUI from '../src/three-mesh-ui.js';
import FontJSON from './assets/Roboto-msdf.json';
import FontImage from './assets/Roboto-msdf.png';

const WIDTH = window.innerWidth;
const HEIGHT = window.innerHeight;

let scene, camera, renderer, controls,
	container, textContainer;

window.addEventListener( 'load', init );
window.addEventListener( 'resize', onWindowResize );

//

function init() {

	scene = new THREE.Scene();
	scene.background = new THREE.Color( 0x505050 );

	camera = new THREE.PerspectiveCamera( 60, WIDTH / HEIGHT, 0.1, 100 );
	camera.position.set( 0, 1.6, 0 );
	camera.lookAt( 0, 1, -1.8 );

	renderer = new THREE.WebGLRenderer( { antialias: true } );
	renderer.localClippingEnabled = true;
	renderer.setPixelRatio( window.devicePixelRatio );
	renderer.setSize( WIDTH, HEIGHT );
	renderer.xr.enabled = true;
	document.body.appendChild( VRButton.createButton( renderer ) );
	document.body.appendChild( renderer.domElement );

	controls = new OrbitControls( camera, renderer.domElement );
	camera.position.set( 0, 1.6, 0 );
	controls.target = new THREE.Vector3( 0, 1, -1.8 );
	controls.update();

	// ROOM

	const room = new THREE.LineSegments(
		new BoxLineGeometry( 6, 6, 6, 10, 10, 10 ).translate( 0, 3, 0 ),
		new THREE.LineBasicMaterial( { color: 0x808080 } )
	);

	scene.add( room );

	// TEXT PANEL

	makeTextPanel();

	//

	renderer.setAnimationLoop( loop );

}

//

function makeTextPanel() {

	const title = new ThreeMeshUI.Block( {
		height: 0.2,
		width: 1.2,
		fontSize: 0.09,
		justifyContent: 'center',
		fontFamily: FontJSON,
		fontTexture: FontImage,
		backgroundColor: new THREE.Color( 'blue' ),
		backgroundOpacity: 0.2
	} ).add(
		new ThreeMeshUI.Text( { content: 'hiddenOverflow attribute :' } )
	);

	title.position.set( 0, 1.8, -2 );
	scene.add( title );

	// !!! BEWARE !!!
	// three-mesh-ui uses three.js local clipping to hide overflows, so don't
	// forget to enable local clipping with renderer.localClippingEnabled = true;

	container = new ThreeMeshUI.Block( {
		height: 0.7,
		width: 0.6,
		padding: 0.05,
		justifyContent: 'center',
		backgroundOpacity: 1,
		backgroundColor: new THREE.Color( 'grey' )
	} );

	container.setupState( {
		state: 'hidden-on',
		attributes: { hiddenOverflow: true }
	} );

	container.setupState( {
		state: 'hidden-off',
		attributes: { hiddenOverflow: false }
	} );

	container.setState( 'hidden-on' );

	container.position.set( 0, 1, -1.8 );
	container.rotation.x = -0.55;
	scene.add( container );

	//

	textContainer = new ThreeMeshUI.Block( {
		width: 1,
		height: 1,
		padding: 0.09,
		backgroundColor: new THREE.Color( 'blue' ),
		backgroundOpacity: 0.2,
		justifyContent: 'center'
	} );

	container.add( textContainer );

	//

	const text = new ThreeMeshUI.Text( {
		content: 'hiddenOverflow '.repeat( 28 ),
		fontSize: 0.054,
		fontFamily: FontJSON,
		fontTexture: FontImage
	} );

	textContainer.add( text );

	setInterval( () => {

		if ( container.currentState === 'hidden-on' ) {

			container.setState( 'hidden-off' );

		} else {

			container.setState( 'hidden-on' );

		}

	}, 1500 );

}

// handles resizing the renderer when the viewport is resized

function onWindowResize() {

	camera.aspect = window.innerWidth / window.innerHeight;
	camera.updateProjectionMatrix();
	renderer.setSize( window.innerWidth, window.innerHeight );

}

//

function loop() {

	// animate user interface

	const x = Math.sin( Date.now() / 2000 ) * 0.25;
	const y = ( Math.cos( Date.now() / 2000 ) * 0.25 );

	container.position.x = x;
	container.position.y = y + 0.85;

	textContainer.position.x = x * 0.6;
	textContainer.position.y = y * 0.6;

	// Don't forget, ThreeMeshUI must be updated manually.
	// This has been introduced in version 3.0.0 in order
	// to improve performance
	ThreeMeshUI.update();

	//

	controls.update();
	renderer.render( scene, camera );

}