<!-- SOLUV · part 203 -->
rent; white: fully opaque).
		 *
		 * Only the color of the texture is used, ignoring the alpha channel if one
		 * exists. For RGB and RGBA textures, the renderer will use the green channel
		 * when sampling this texture due to the extra bit of precision provided for
		 * green in DXT-compressed and uncompressed RGB 565 formats. Luminance-only and
		 * luminance/alpha textures will also still work as expected.
		 *
		 * `alphaMap` represents non-color data. Any texture assigned must have
		 * `texture.colorSpace = NoColorSpace` (default).
		 *
		 * @type {?Texture}
		 * @default null
		 */
		this.alphaMap = null;

		/**
		 * The environment map. To ensure a physically correct rendering, environment maps
		 * are internally pre-processed with {@link PMREMGenerator}.
		 *
		 * `envMap` represents luminance data, and the texture must be assigned
		 * a {@link Texture#colorSpace}. Most `envMap` textures set
		 * `texture.colorSpace = LinearSRGBColorSpace` and use float-type formats
		 * such as `.exr` or `.hdr`.
		 *
		 * @type {?Texture}
		 * @default null
		 */
		this.envMap = null;

		/**
		 * The rotation of the environment map in radians.
		 *
		 * @type {Euler}
		 * @default (0,0,0)
		 */
		this.envMapRotation = new Euler();

		/**
		 * Scales the effect of the environment map by multiplying its color.
		 *
		 * @type {number}
		 * @default 1
		 */
		this.envMapIntensity = 1.0;

		/**
		 * Renders the geometry as a wireframe.
		 *
		 * @type {boolean}
		 * @default false
		 */
		this.wireframe = false;

		/**
		 * Controls the thickness of the wireframe.
		 *
		 * Can only be used with {@link SVGRenderer}.
		 *
		 * @type {number}
		 * @default 1
		 */
		this.wireframeLinewidth = 1;

		/**
		 * Defines appearance of wireframe ends.
		 *
		 * Can only be used with {@link SVGRenderer}.
		 *
		 * @type {('round'|'bevel'|'miter')}
		 * @default 'round'
		 */
		this.wireframeLinecap = 'round';

		/**
		 * Defines appearance of wireframe joints.
		 *
		 * Can only be used with {@link SVGRenderer}.
		 *
		 * @type {('round'|'bevel'|'miter')}
		 * @default 'round'
		 */
		this.wireframeLinejoin = 'round';

		/**
		 * Whether the material is rendered with flat shading or not.
		 *
		 * @type {boolean}
		 * @default false
		 */
		this.flatShading = false;

		/**
		 * Whether the material is affected by fog or not.
		 *
		 * @type {boolean}
		 * @default true
		 */
		this.fog = true;

		this.setValues( parameters );

	}

	copy( source ) {

		super.copy( source );

		this.defines = { 'STANDARD': '' };

		this.color.copy( source.color );
		this.roughness = source.roughness;
		this.metalness = source.metalness;

		this.map = source.map;

		this.lightMap = source.lightMap;
		this.lightMapIntensity = source.lightMapIntensity;

		this.aoMap = source.aoMap;
		this.aoMapIntensity = source.aoMapIntensity;

		this.emissive.copy( source.emissive );
		this.emissiveMap = source.emissiveMap;
		this.emissiveIntensity = source.emissiveIntensity;

		this.bumpMap = source.bumpMap;
		this.bumpScale = source.bumpScale;

		this.normalMap = source.normalMap;
		this.normalMapType = source.normalMapType;
		this.normalScale.copy( source.normalScale );

		this.displacementMap = source.displacementMap;
		this.displacementScale = source.displacementScale;
		this.displacementBias = source.displacementBias;

		this.roughnessMap = source.roughnessMap;

		this.metalnessMap = source.metalnessMap;

		this.alphaMap = source.alphaMap;

		this.envMap = source.envMap;
		this.envMapRotation.copy( source.envMapRotation );
		this.envMapIntensity = source.envMapIntensity;

		this.wireframe = source.wireframe;
		this.wireframeLinewidth = source.wireframeLinewidth;
		this.wireframeLinecap = source.wireframeLinecap;
		this.wireframeLinejoin = source.wireframeLinejoin;

		this.flatShading = source.flatShading;

		this.fog = source.fog;

		return this;

	}

}

/**
 * An extension of the {@link MeshStandardMaterial}, providing more advanced
 * physically-based rendering properties:
 *
 * - Anisotropy: Ability to represent the anisotropic property of materials
 * as observable with brushed metals.
 * - Clearcoat: Some materials — like car paints, carbon fiber, and wet surfaces — require
 * a clear, reflective layer on top of another layer that may be irregular or rough.
 * Clearcoat approximates this effect, without the need for a separate transparent surface.
 * - Iridescence: Allows to render the effect where hue varies  depending on the viewing
 * angle and illumination angle. This can be seen on soap bubbles, oil films, or on the
 * wings of many insects.
 * - Physically-based transparency: One limitation of {@link Material#opacity} is that highly
 * transparent materials are less reflective. Physically-based transmission provides a more
 * realistic option for thin, transparent surfaces like glass.
 * - Advanced reflectivity: More flexible reflectivity for non-metallic materials.
 * - Retroreflection: Redirects specular light bac