[page:Loader] →

# [name]

A loader for glTF 2.0 resources.
[link:https://www.khronos.org/gltf glTF] (GL Transmission Format) is an [link:https://github.com/KhronosGroup/glTF/tree/master/specification/2.0 open format specification] for efficient delivery and loading of 3D content. Assets may be provided either in JSON (.gltf) or binary (.glb) format. External files store textures (.jpg, .png) and additional binary data (.bin). A glTF asset may deliver one or more scenes, including meshes, materials, textures, skins, skeletons, morph targets, animations, lights, and/or cameras.

## Extensions

GLTFLoader supports the following [link:https://github.com/KhronosGroup/glTF/tree/master/extensions/ glTF 2.0 extensions]:

- KHR_draco_mesh_compression
- KHR_materials_pbrSpecularGlossiness
- KHR_materials_unlit
- KHR_mesh_quantization
- KHR_lights_punctual1
- KHR_texture_transform2
- MSFT_texture_dds

1Requires [link:https://threejs.org/docs/#api/en/renderers/WebGLRenderer.physicallyCorrectLights physicallyCorrectLights] to be enabled.

2UV transforms are supported, with several key limitations. Transforms applied to a texture using the first UV slot (all textures except aoMap and lightMap) must share the same transform, or no transfor at all. The aoMap and lightMap textures cannot be transformed. No more than one transform may be used per material. Each use of a texture with a unique transform will result in an additional GPU texture upload. See #[link:https://github.com/mrdoob/three.js/pull/13831 13831] and #[link:https://github.com/mrdoob/three.js/issues/12788 12788].

## Example

`// Instantiate a loader var loader = new THREE.GLTFLoader(); // Optional: Provide a DRACOLoader instance to decode compressed mesh data var dracoLoader = new THREE.DRACOLoader(); dracoLoader.setDecoderPath( '/examples/js/libs/draco/' ); loader.setDRACOLoader( dracoLoader ); // Load a glTF resource loader.load( // resource URL 'models/gltf/duck/duck.gltf', // called when the resource is loaded function ( gltf ) { scene.add( gltf.scene ); gltf.animations; // Array<THREE.AnimationClip> gltf.scene; // THREE.Scene gltf.scenes; // Array<THREE.Scene> gltf.cameras; // Array<THREE.Camera> gltf.asset; // Object }, // called while loading is progressing function ( xhr ) { console.log( ( xhr.loaded / xhr.total * 100 ) + '% loaded' ); }, // called when loading has errors function ( error ) { console.log( 'An error happened' ); } );` [example:webgl_loader_gltf]

## Browser compatibility

GLTFLoader relies on ES6 [link:https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise Promises], which are not supported in IE11. To use the loader in IE11, you must [link:https://github.com/stefanpenner/es6-promise include a polyfill] providing a Promise replacement.

## Textures

Textures containing color information (.map, .emissiveMap, and .specularMap) always use sRGB colorspace in glTF, while vertex colors and material properties (.color, .emissive, .specular) use linear colorspace. In a typical rendering workflow, textures are converted to linear colorspace by the renderer, lighting calculations are made, then final output is converted back to sRGB and displayed on screen. Unless you need post-processing in linear colorspace, always configure [page:WebGLRenderer] as follows when using glTF:

`renderer.gammaOutput = true; renderer.gammaFactor = 2.2;`

GLTFLoader will automatically configure textures referenced from a .gltf or .glb file correctly, with the assumption that the renderer is set up as shown above. When loading textures externally (e.g., using [page:TextureLoader]) and applying them to a glTF model, colorspace and orientation must be given:

`// If texture is used for color information, set colorspace. texture.encoding = THREE.sRGBEncoding; // UVs use the convention that (0, 0) corresponds to the upper left corner of a texture. texture.flipY = false;`

## Custom extensions

Metadata from unknown extensions is preserved as “.userData.gltfExtensions” on Object3D, Scene, and Material instances, or attached to the response “gltf” object. Example:

`loader.load('foo.gltf', function ( gltf ) { var scene = gltf.scene; var mesh = scene.children[ 3 ]; var fooExtension = mesh.userData.gltfExtensions.EXT_foo; gltf.parser.getDependency( 'bufferView', fooExtension.bufferView ) .then( function ( fooBuffer ) { ... } ); } );`

## Constructor

### [name]( [param:LoadingManager manager] )

[page:LoadingManager manager] — The [page:LoadingManager loadingManager] for the loader to use. Default is [page:LoadingManager THREE.DefaultLoadingManager].

Creates a new [name].

## Properties

See the base [page:Loader] class for common properties.

## Methods

See the base [page:Loader] class for common methods.

### [method:null load]( [param:String url], [param:Function onLoad], [param:Function onProgress], [param:Function onError] )

[page:String url] — A string containing the path/URL of the .gltf or .glb file.
[page:Function onLoad] — A function to be called after the loading is successfully completed. The function receives the loaded JSON response returned from [page:Function parse].
[page:Function onProgress] — (optional) A function to be called while the loading is in progress. The argument will be the XMLHttpRequest instance, that contains .[page:Integer total] and .[page:Integer loaded] bytes.
[page:Function onError] — (optional) A function to be called if an error occurs during loading. The function receives error as an argument.

Begin loading from url and call the callback function with the parsed response content.

### [method:null setDRACOLoader]( [param:DRACOLoader dracoLoader] )

[page:DRACOLoader dracoLoader] — Instance of THREE.DRACOLoader, to be used for decoding assets compressed with the KHR_draco_mesh_compression extension.

Refer to this [link:https://github.com/mrdoob/three.js/tree/dev/examples/js/libs/draco#readme readme] for the details of Draco and its decoder.

### [method:null setDDSLoader]( [param:DDSLoader ddsLoader] )

[page:DDSLoader ddsLoader] — Instance of THREE.DDSLoader, to be used for loading compressed textures with the MSFT_TEXTURE_DDS extension.

### [method:null parse]( [param:ArrayBuffer data], [param:String path], [param:Function onLoad], [param:Function onError] )

[page:ArrayBuffer data] — glTF asset to parse, as an ArrayBuffer or JSON string.
[page:String path] — The base path from which to find subsequent glTF resources such as textures and .bin data files.
[page:Function onLoad] — A function to be called when parse completes.
[page:Function onError] — (optional) A function to be called if an error occurs during parsing. The function receives error as an argument.

Parse a glTF-based ArrayBuffer or JSON String and fire [page:Function onLoad] callback when complete. The argument to [page:Function onLoad] will be an [page:object] that contains loaded parts: .[page:Scene scene], .[page:Array scenes], .[page:Array cameras], .[page:Array animations], and .[page:Object asset].

## Source

[link:https://github.com/mrdoob/three.js/blob/master/examples/js/loaders/GLTFLoader.js examples/js/loaders/GLTFLoader.js]