constructor( manager ) {

		super( manager );

		this.dracoLoader = null;
		this.ktx2Loader = null;
		this.meshoptDecoder = null;

		this.pluginCallbacks = [];

		this.register( function ( parser ) {

			return new GLTFMaterialsClearcoatExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFMaterialsDispersionExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFTextureBasisUExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFTextureWebPExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFTextureAVIFExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFMaterialsSheenExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFMaterialsTransmissionExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFMaterialsVolumeExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFMaterialsIorExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFMaterialsEmissiveStrengthExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFMaterialsSpecularExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFMaterialsIridescenceExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFMaterialsAnisotropyExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFMaterialsBumpExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFLightsExtension( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFMeshoptCompression( parser );

		} );

		this.register( function ( parser ) {

			return new GLTFMeshGpuInstancing( parser );

		} );

	}
Constructs a new glTF loader.

@param {LoadingManager} [manager] - The loading manager.