[name]

Handles and keeps track of loaded and pending data. A default global instance of this class is created and used by loaders if not supplied manually - see [page:DefaultLoadingManager].

In general that should be sufficient, however there are times when it can be useful to have seperate loaders - for example if you want to show seperate loading bars for objects and textures.

Example

[example:webgl_loader_babylon WebGL / loader / babylon]
[example:webgl_loader_fbx WebGL / loader / fbx]
[example:webgl_loader_obj WebGL / loader / obj]
[example:webgl_materials_reflectivity WebGL / materials / reflectivity]
[example:webgl_postprocessing_outline WebGL / postprocesing / outline]
[example:webgl_terrain_dynamic WebGL / terrain / dynamic]

This example shows how to use LoadingManager to track the progress of [page:OBJLoader].


		var manager = new THREE.LoadingManager();
		manager.onStart = function ( url, itemsLoaded, itemsTotal ) {

			console.log( 'Started loading file: ' + url + '.\nLoaded ' + itemsLoaded + ' of ' + itemsTotal + ' files.' );

		};

		manager.onLoad = function ( ) {

			console.log( 'Loading complete!');

		};


		manager.onProgress = function ( url, itemsLoaded, itemsTotal ) {

			console.log( 'Loading file: ' + url + '.\nLoaded ' + itemsLoaded + ' of ' + itemsTotal + ' files.' );

		};

		manager.onError = function ( url ) {

			console.log( 'There was an error loading ' + url );

		};

		var loader = new THREE.OBJLoader( manager );
		loader.load( 'file.obj', function ( object ) {

			//

		} );

In addition to observing progress, a LoadingManager can be used to override resource URLs during loading. This may be helpful for assets coming from drag-and-drop events, WebSockets, WebRTC, or other APIs. An example showing how to load an in-memory model using Blob URLs is below.


		// Blob or File objects created when dragging files into the webpage.
		var blobs = {'fish.gltf': blob1, 'diffuse.png': blob2, 'normal.png': blob3};

		var manager = new THREE.LoadingManager();

		// Initialize loading manager with URL callback.
		var objectURLs = [];
		manager.setURLModifier( ( url ) => {

			url = URL.createObjectURL( blobs[ url ] );

			objectURLs.push( url );

			return url;

		} );

		// Load as usual, then revoke the blob URLs.
		var loader = new THREE.GLTFLoader( manager );
		loader.load( 'fish.gltf', (gltf) => {

			scene.add( gltf.scene );

			objectURLs.forEach( ( url ) => URL.revokeObjectURL( url ) );

		});

Constructor

[name]( [param:Function onLoad], [param:Function onProgress], [param:Function onError] )

[page:Function onLoad] — (optional) this function will be called when all loaders are done.
[page:Function onProgress] — (optional) this function will be called when an item is complete.
[page:Function onError] — (optional) this function will be called a loader encounters errors.
Creates a new [name].

Properties

[property:Function onStart]

This function will be called when loading starts. The arguments are:
[page:String url] — The url of the item just loaded.
[page:Integer itemsLoaded] — the number of items already loaded so far.
[page:Iteger itemsTotal] — the total amount of items to be loaded.

By default this is undefined.

[property:Function onLoad]

This function will be called when all loading is completed. By default this is undefined, unless passed in the constructor.

[property:Function onProgress]

This function will be called when an item is complete. The arguments are:
[page:String url] — The url of the item just loaded.
[page:Integer itemsLoaded] — the number of items already loaded so far.
[page:Iteger itemsTotal] — the total amount of items to be loaded.

By default this is undefined, unless passed in the constructor.

[property:Function onError]

This function will be called when any item errors, with the argument:
[page:String url] — The url of the item that errored.

By default this is undefined, unless passed in the constructor.

Methods

[method:null setURLModifier]( [param:Function callback] )

[page:Function callback] — URL modifier callback. Called with [page:String url] argument, and must return [page:String resolvedURL].

If provided, the callback will be passed each resource URL before a request is sent. The callback may return the original URL, or a new URL to override loading behavior. This behavior can be used to load assets from .ZIP files, drag-and-drop APIs, and Data URIs.

[method:String resolveURL]( [param:String url] )

[page:String url] — the url to load

Given a URL, uses the URL modifier callback (if any) and returns a resolved URL. If no URL modifier is set, returns the original URL.

Note: The following methods are designed to be called internally by loaders. You shouldn't call them directly.

[method:null itemStart]( [param:String url] )

[page:String url] — the url to load

This should be called by any loader using the manager when the loader starts loading an url.

[method:null itemEnd]( [param:String url] )

[page:String url] — the loaded url

This should be called by any loader using the manager when the loader ended loading an url.

[method:null itemError]( [param:String url] )

[page:String url] — the loaded url

This should be called by any loader using the manager when the loader errors loading an url.

Source

[link:https://github.com/mrdoob/three.js/blob/master/src/loaders/LoadingManager.js src/loaders/LoadingManager.js]