constructor( camera, tCube, opacity = 1 ) {

		super();

		/**
		 * The camera.
		 *
		 * @type {PerspectiveCamera}
		 */
		this.camera = camera;

		/**
		 * The cube texture to render.
		 *
		 * @type {CubeTexture}
		 */
		this.tCube = tCube;

		/**
		 * The opacity.
		 *
		 * @type {number}
		 * @default 1
		 */
		this.opacity = opacity;

		/**
		 * Overwritten to disable the swap.
		 *
		 * @type {boolean}
		 * @default false
		 */
		this.needsSwap = false;

		// internals

		const cubeShader = ShaderLib[ 'cube' ];

		this._cubeMesh = new Mesh(
			new BoxGeometry( 10, 10, 10 ),
			new ShaderMaterial( {
				uniforms: UniformsUtils.clone( cubeShader.uniforms ),
				vertexShader: cubeShader.vertexShader,
				fragmentShader: cubeShader.fragmentShader,
				depthTest: false,
				depthWrite: false,
				side: BackSide
			} )
		);

		Object.defineProperty( this._cubeMesh.material, 'envMap', {

			get: function () {

				return this.uniforms.tCube.value;

			}

		} );

		this._cubeScene = new Scene();
		this._cubeCamera = new PerspectiveCamera();
		this._cubeScene.add( this._cubeMesh );

	}
Constructs a new cube texture pass.

@param {PerspectiveCamera} camera - The camera.
@param {CubeTexture} tCube - The cube texture to render.
@param {number} [opacity=1] - The opacity.