three.js/src/loaders/GeometryLoader.js

/**
 * @author mrdoob / http://mrdoob.com/
 */

THREE.GeometryLoader = function ( manager ) {

	this.manager = ( manager !== undefined ) ? manager : THREE.DefaultLoadingManager;

};

THREE.GeometryLoader.prototype = {

	constructor: THREE.GeometryLoader,

	load: function ( url, onLoad, onProgress, onError ) {

		var scope = this;

		var loader = new THREE.XHRLoader();
		loader.setCrossOrigin( this.crossOrigin );
		loader.load( url, function ( text ) {

			onLoad( scope.parse( JSON.parse( text ) ) );

		}, onProgress, onError );

	},

	setCrossOrigin: function ( value ) {

		this.crossOrigin = value;

	},

	parse: function ( json ) {

		var geometry = new THREE.Geometry();

		geometry.indices = json.indices;
		geometry.vertices = json.vertices;
		geometry.normals = json.normals;
		geometry.uvs = json.uvs;

		var boundingSphere = json.boundingSphere;

		if ( boundingSphere !== undefined ) {

			geometry.boundingSphere = new THREE.Sphere(
				new THREE.Vector3().fromArray( boundingSphere.center !== undefined ? boundingSphere.center : [ 0, 0, 0 ] ),
				boundingSphere.radius
			);

		}

		return geometry;

	}

};