three
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JavaScript 3D library
280 lines (176 loc) • 6.43 kB
JavaScript
import {
FileLoader,
Loader
} from 'three';
import { unzipSync } from '../libs/fflate.module.js';
import { USDAParser } from './usd/USDAParser.js';
import { USDCParser } from './usd/USDCParser.js';
import { USDComposer } from './usd/USDComposer.js';
/**
* A loader for the USD format (USD, USDA, USDC, USDZ).
*
* Supports both ASCII (USDA) and binary (USDC) USD files, as well as
* USDZ archives containing either format.
*
* ```js
* const loader = new USDLoader();
* const model = await loader.loadAsync( 'model.usdz' );
* scene.add( model );
* ```
*
* @augments Loader
* @three_import import { USDLoader } from 'three/addons/loaders/USDLoader.js';
*/
class USDLoader extends Loader {
/**
* Constructs a new USDZ loader.
*
* @param {LoadingManager} [manager] - The loading manager.
*/
constructor( manager ) {
super( manager );
}
/**
* Starts loading from the given URL and passes the loaded USDZ asset
* to the `onLoad()` callback.
*
* @param {string} url - The path/URL of the file to be loaded. This can also be a data URI.
* @param {function(Group)} onLoad - Executed when the loading process has been finished.
* @param {onProgressCallback} onProgress - Executed while the loading is in progress.
* @param {onErrorCallback} onError - Executed when errors occur.
*/
load( url, onLoad, onProgress, onError ) {
const scope = this;
const loader = new FileLoader( scope.manager );
loader.setPath( scope.path );
loader.setResponseType( 'arraybuffer' );
loader.setRequestHeader( scope.requestHeader );
loader.setWithCredentials( scope.withCredentials );
loader.load( url, function ( text ) {
try {
onLoad( scope.parse( text ) );
} catch ( e ) {
if ( onError ) {
onError( e );
} else {
console.error( e );
}
scope.manager.itemError( url );
}
}, onProgress, onError );
}
/**
* Parses the given USDZ data and returns the resulting group.
*
* @param {ArrayBuffer|string} buffer - The raw USDZ data as an array buffer.
* @return {Group} The parsed asset as a group.
*/
parse( buffer ) {
const usda = new USDAParser();
const usdc = new USDCParser();
const textDecoder = new TextDecoder();
function toArrayBuffer( data ) {
if ( data instanceof ArrayBuffer ) return data;
if ( data.byteOffset === 0 && data.byteLength === data.buffer.byteLength ) {
return data.buffer;
}
return data.buffer.slice( data.byteOffset, data.byteOffset + data.byteLength );
}
function getLowercaseExtension( filename ) {
const lastDot = filename.lastIndexOf( '.' );
if ( lastDot < 0 ) return '';
const lastSlash = filename.lastIndexOf( '/' );
if ( lastSlash > lastDot ) return '';
return filename.slice( lastDot + 1 ).toLowerCase();
}
function parseAssets( zip ) {
const data = {};
for ( const filename in zip ) {
const fileBytes = zip[ filename ];
const ext = getLowercaseExtension( filename );
if ( ext === 'png' || ext === 'jpg' || ext === 'jpeg' || ext === 'avif' ) {
// Keep raw image bytes and create object URLs lazily in USDComposer.
data[ filename ] = fileBytes;
continue;
}
if ( ext !== 'usd' && ext !== 'usda' && ext !== 'usdc' ) continue;
if ( isCrateFile( fileBytes ) ) {
data[ filename ] = usdc.parseData( toArrayBuffer( fileBytes ) );
} else {
data[ filename ] = usda.parseData( textDecoder.decode( fileBytes ) );
}
}
return data;
}
function isCrateFile( buffer ) {
const crateHeader = new Uint8Array( [ 0x50, 0x58, 0x52, 0x2D, 0x55, 0x53, 0x44, 0x43 ] ); // PXR-USDC
const view = buffer instanceof Uint8Array ? buffer : new Uint8Array( buffer );
if ( view.byteLength < crateHeader.length ) return false;
for ( let i = 0; i < crateHeader.length; i ++ ) {
if ( view[ i ] !== crateHeader[ i ] ) return false;
}
return true;
}
function findUSD( zip ) {
const fileNames = Object.keys( zip );
if ( fileNames.length < 1 ) return { file: undefined, filename: '', basePath: '' };
const firstFileName = fileNames[ 0 ];
const ext = getLowercaseExtension( firstFileName );
let isCrate = false;
const lastSlash = firstFileName.lastIndexOf( '/' );
const basePath = lastSlash >= 0 ? firstFileName.slice( 0, lastSlash ) : '';
// Per AOUSD core spec v1.0.1 section 16.4.1.2, the first ZIP entry is the root layer.
// ASCII files can end in either .usda or .usd.
if ( ext === 'usda' ) return { file: zip[ firstFileName ], filename: firstFileName, basePath };
if ( ext === 'usdc' ) {
isCrate = true;
} else if ( ext === 'usd' ) {
// If this is not a crate file, we assume it is a plain USDA file.
if ( ! isCrateFile( zip[ firstFileName ] ) ) {
return { file: zip[ firstFileName ], filename: firstFileName, basePath };
} else {
isCrate = true;
}
}
if ( isCrate ) {
return { file: zip[ firstFileName ], filename: firstFileName, basePath };
}
return { file: undefined, filename: '', basePath: '' };
}
const scope = this;
// USDA (standalone)
if ( typeof buffer === 'string' ) {
const composer = new USDComposer( scope.manager );
const data = usda.parseData( buffer );
return composer.compose( data, {} );
}
// USDC (standalone)
if ( isCrateFile( buffer ) ) {
const composer = new USDComposer( scope.manager );
const data = usdc.parseData( toArrayBuffer( buffer ) );
return composer.compose( data, {} );
}
const bytes = new Uint8Array( buffer );
// USDZ
if ( bytes[ 0 ] === 0x50 && bytes[ 1 ] === 0x4B ) {
const zip = unzipSync( bytes );
const assets = parseAssets( zip );
const { file, filename, basePath } = findUSD( zip );
if ( ! file ) {
throw new Error( 'USDLoader: Invalid USDZ package. The first ZIP entry must be a USD layer (.usd/.usda/.usdc).' );
}
const composer = new USDComposer( scope.manager );
const data = assets[ filename ];
if ( ! data ) {
throw new Error( 'USDLoader: Failed to parse root layer "' + filename + '".' );
}
return composer.compose( data, assets, {}, basePath );
}
// USDA (standalone, as ArrayBuffer)
const composer = new USDComposer( scope.manager );
const text = textDecoder.decode( bytes );
const data = usda.parseData( text );
return composer.compose( data, {} );
}
}
export { USDLoader };