<!-- SOLUV · part 159 -->
?(NeverCompare|LessCompare|EqualCompare|LessEqualCompare|GreaterCompare|NotEqualCompare|GreaterEqualCompare|AlwaysCompare)}
		 * @default null
		 */
		this.compareFunction = null;

	}


	copy( source ) {

		super.copy( source );

		this.source = new TextureSource( Object.assign( {}, source.image ) ); // see #30540
		this.compareFunction = source.compareFunction;

		return this;

	}

	toJSON( meta ) {

		const data = super.toJSON( meta );

		data.compareFunction = this.compareFunction;

		return data;

	}

}

/**
 * This class can be used to automatically save the depth information of a
 * cube rendering into a cube texture with depth format. Used for PointLight shadows.
 *
 * @augments DepthTexture
 */
class CubeDepthTexture extends DepthTexture {

	/**
	 * Constructs a new cube depth texture.
	 *
	 * @param {number} size - The size (width and height) of each cube face.
	 * @param {number} [type=UnsignedIntType] - The texture type.
	 * @param {number} [mapping=CubeReflectionMapping] - The texture mapping.
	 * @param {number} [wrapS=ClampToEdgeWrapping] - The wrapS value.
	 * @param {number} [wrapT=ClampToEdgeWrapping] - The wrapT value.
	 * @param {number} [magFilter=NearestFilter] - The mag filter value.
	 * @param {number} [minFilter=NearestFilter] - The min filter value.
	 * @param {number} [anisotropy=Texture.DEFAULT_ANISOTROPY] - The anisotropy value.
	 * @param {number} [format=DepthFormat] - The texture format.
	 */
	constructor( size, type = UnsignedIntType, mapping = CubeReflectionMapping, wrapS, wrapT, magFilter = NearestFilter, minFilter = NearestFilter, anisotropy, format = DepthFormat ) {

		// Create 6 identical image descriptors for the cube faces
		const image = { width: size, height: size, depth: 1 };
		const images = [ image, image, image, image, image, image ];

		// Call DepthTexture constructor with width, height
		super( size, size, type, mapping, wrapS, wrapT, magFilter, minFilter, anisotropy, format );

		// Replace the single image with the array of 6 images
		this.image = images;

		/**
		 * This flag can be used for type testing.
		 *
		 * @type {boolean}
		 * @readonly
		 * @default true
		 */
		this.isCubeDepthTexture = true;

		/**
		 * Set to true for cube texture handling in WebGLTextures.
		 *
		 * @type {boolean}
		 * @readonly
		 * @default true
		 */
		this.isCubeTexture = true;

	}

	/**
	 * Alias for {@link CubeDepthTexture#image}.
	 *
	 * @type {Array<Image>}
	 */
	get images() {

		return this.image;

	}

	set images( value ) {

		this.image = value;

	}

}

/**
 * Represents a texture created externally with the same renderer context.
 *
 * This may be a texture from a protected media stream, device camera feed,
 * or other data feeds like a depth sensor.
 *
 * @augments Texture
 */
class ExternalTexture extends Texture {

	/**
	 * Creates a new raw texture.
	 *
	 * @param {?(WebGLTexture|GPUTexture)} [sourceTexture=null] - The external texture.
	 */
	constructor( sourceTexture = null ) {

		super();

		/**
		 * The external source texture.
		 *
		 * @type {?(WebGLTexture|GPUTexture)}
		 * @default null
		 */
		this.sourceTexture = sourceTexture;

		/**
		 * This flag can be used for type testing.
		 *
		 * @type {boolean}
		 * @readonly
		 * @default true
		 */
		this.isExternalTexture = true;

	}

	copy( source ) {

		super.copy( source );

		this.sourceTexture = source.sourceTexture;

		return this;

	}

}

/**
 * A geometry class for a rectangular cuboid with a given width, height, and depth.
 * On creation, the cuboid is centred on the origin, with each edge parallel to one
 * of the axes.
 *
 * ```js
 * const geometry = new THREE.BoxGeometry( 1, 1, 1 );
 * const material = new THREE.MeshBasicMaterial( { color: 0x00ff00 } );
 * const cube = new THREE.Mesh( geometry, material );
 * scene.add( cube );
 * ```
 *
 * @augments BufferGeometry
 * @demo scenes/geometry-browser.html#BoxGeometry
 */
class BoxGeometry extends BufferGeometry {

	/**
	 * Constructs a new box geometry.
	 *
	 * @param {number} [width=1] - The width. That is, the length of the edges parallel to the X axis.
	 * @param {number} [height=1] - The height. That is, the length of the edges parallel to the Y axis.
	 * @param {number} [depth=1] - The depth. That is, the length of the edges parallel to the Z axis.
	 * @param {number} [widthSegments=1] - Number of segmented rectangular faces along the width of the sides.
	 * @param {number} [heightSegments=1] - Number of segmented rectangular faces along the height of the sides.
	 * @param {number} [depthSegments=1] - Number of segmented rectangular faces along the depth of the sides.
	 */
	constructor( width = 1, height = 1, depth = 1, widthSegments = 1, heightSegments = 1, depthSegments = 1 ) {

		super();

		this.type = 'BoxGeometry';

		/**
		 * Holds the constructor parameters that have been
		 * used to generate the geometry. Any modification
		 * after instantiation does not change the geometry.
		 *
		 * @type {Object}