<!-- NEW3 — TEST 3 · THE RIVER'S JOURNEY · part 197 -->
niformsLib[ 'fog' ], shaderUniforms ] );
		 *     vertexShader: vertexShader,
		 *     fragmentShader: fragmentShader,
		 *     fog: true
		 * } );
		 * ```
		 *
		 * @type {boolean}
		 * @default false
		 */
		this.fog = false;

		/**
		 * Defines whether this material uses lighting; `true` to pass uniform data
		 * related to lighting to this shader.
		 *
		 * @type {boolean}
		 * @default false
		 */
		this.lights = false;

		/**
		 * Defines whether this material supports clipping; `true` to let the renderer
		 * pass the clippingPlanes uniform.
		 *
		 * @type {boolean}
		 * @default false
		 */
		this.clipping = false;

		/**
		 * Overwritten and set to `true` by default.
		 *
		 * @type {boolean}
		 * @default true
		 */
		this.forceSinglePass = true;

		/**
		 * This object allows to enable certain WebGL 2 extensions.
		 *
		 * - clipCullDistance: set to `true` to use vertex shader clipping
		 * - multiDraw: set to `true` to use vertex shader multi_draw / enable gl_DrawID
		 *
		 * @type {{clipCullDistance:false,multiDraw:false}}
		 */
		this.extensions = {
			clipCullDistance: false, // set to use vertex shader clipping
			multiDraw: false // set to use vertex shader multi_draw / enable gl_DrawID
		};

		/**
		 * When the rendered geometry doesn't include these attributes but the
		 * material does, these default values will be passed to the shaders. This
		 * avoids errors when buffer data is missing.
		 *
		 * - color: [ 1, 1, 1 ]
		 * - uv: [ 0, 0 ]
		 * - uv1: [ 0, 0 ]
		 *
		 * @type {Object}
		 */
		this.defaultAttributeValues = {
			'color': [ 1, 1, 1 ],
			'uv': [ 0, 0 ],
			'uv1': [ 0, 0 ]
		};

		/**
		 * If set, this calls [gl.bindAttribLocation](https://developer.mozilla.org/en-US/docs/Web/API/WebGLRenderingContext/bindAttribLocation)
		 * to bind a generic vertex index to an attribute variable.
		 *
		 * @type {string|undefined}
		 * @default undefined
		 */
		this.index0AttributeName = undefined;

		/**
		 * Can be used to force a uniform update while changing uniforms in
		 * {@link Object3D#onBeforeRender}.
		 *
		 * @type {boolean}
		 * @default false
		 */
		this.uniformsNeedUpdate = false;

		/**
		 * Defines the GLSL version of custom shader code.
		 *
		 * @type {?(GLSL1|GLSL3)}
		 * @default null
		 */
		this.glslVersion = null;

		if ( parameters !== undefined ) {

			this.setValues( parameters );

		}

	}

	copy( source ) {

		super.copy( source );

		this.fragmentShader = source.fragmentShader;
		this.vertexShader = source.vertexShader;

		this.uniforms = cloneUniforms( source.uniforms );
		this.uniformsGroups = cloneUniformsGroups( source.uniformsGroups );

		this.defines = Object.assign( {}, source.defines );

		this.wireframe = source.wireframe;
		this.wireframeLinewidth = source.wireframeLinewidth;

		this.fog = source.fog;
		this.lights = source.lights;
		this.clipping = source.clipping;

		this.extensions = Object.assign( {}, source.extensions );

		this.glslVersion = source.glslVersion;

		this.defaultAttributeValues = Object.assign( {}, source.defaultAttributeValues );

		this.index0AttributeName = source.index0AttributeName;

		this.uniformsNeedUpdate = source.uniformsNeedUpdate;

		return this;

	}

	toJSON( meta ) {

		const data = super.toJSON( meta );

		data.glslVersion = this.glslVersion;
		data.uniforms = {};

		for ( const name in this.uniforms ) {

			const uniform = this.uniforms[ name ];
			const value = uniform.value;

			if ( value && value.isTexture ) {

				data.uniforms[ name ] = {
					type: 't',
					value: value.toJSON( meta ).uuid
				};

			} else if ( value && value.isColor ) {

				data.uniforms[ name ] = {
					type: 'c',
					value: value.getHex()
				};

			} else if ( value && value.isVector2 ) {

				data.uniforms[ name ] = {
					type: 'v2',
					value: value.toArray()
				};

			} else if ( value && value.isVector3 ) {

				data.uniforms[ name ] = {
					type: 'v3',
					value: value.toArray()
				};

			} else if ( value && value.isVector4 ) {

				data.uniforms[ name ] = {
					type: 'v4',
					value: value.toArray()
				};

			} else if ( value && value.isMatrix3 ) {

				data.uniforms[ name ] = {
					type: 'm3',
					value: value.toArray()
				};

			} else if ( value && value.isMatrix4 ) {

				data.uniforms[ name ] = {
					type: 'm4',
					value: value.toArray()
				};

			} else {

				data.uniforms[ name ] = {
					value: value
				};

				// note: the array variants v2v, v3v, v4v, m4v and tv are not supported so far

			}

		}

		if ( Object.keys( this.defines ).length > 0 ) data.defines = this.defines;

		data.vertexShader = this.vertexShader;
		data.fragmentShader = this.fragmentShader;

		data.lights = this.lights;
		data.clipping = this.clipping;

		const extensions = {};

		for ( const key in this.extensions ) {

			if ( this.extensions[ key ] === true ) extensions[ key ] = true;

		}

		if ( Object.keys( extensions ).length > 0 ) data.extensions = extensions;