Accueil / npm / three@0.186.1 / src / loaders / Cache.js
Cache.js
/**
* @class
* @classdesc A simple caching system, used internally by {@link FileLoader}.
* To enable caching across all loaders that use {@link FileLoader}, add `THREE.Cache.enabled = true.` once in your app.
* @hideconstructor
*/
const Cache = {
/**
* Whether caching is enabled or not.
*
* @static
* @type {boolean}
* @default false
*/
enabled: false,
/**
* A dictionary that holds cached files.
*
* @static
* @type {Object<string,Object>}
*/
files: {},
/**
* Adds a cache entry with a key to reference the file. If this key already
* holds a file, it is overwritten.
*
* @static
* @param {string} key - The key to reference the cached file.
* @param {Object} file - The file to be cached.
*/
add: function ( key, file ) {
if ( this.enabled === false ) return;
if ( isBlobURL( key ) ) return;
// log( 'Cache', 'Adding key:', key );
this.files[ key ] = file;
},
/**
* Gets the cached value for the given key.
*
* @static
* @param {string} key - The key to reference the cached file.
* @return {Object|undefined} The cached file. If the key does not exist `undefined` is returned.
*/
get: function ( key ) {
if ( this.enabled === false ) return;
if ( isBlobURL( key ) ) return;
// log( 'Cache', 'Checking key:', key );
return this.files[ key ];
},
/**
* Removes the cached file associated with the given key.
*
* @static
* @param {string} key - The key to reference the cached file.
*/
remove: function ( key ) {
delete this.files[ key ];
},
/**
* Remove all values from the cache.
*
* @static
*/
clear: function () {
this.files = {};
}
};
/**
* Returns true if the given cache key contains the blob: scheme.
*
* @private
* @param {string} key - The cache key.
* @return {boolean} Whether the given cache key contains the blob: scheme or not.
*/
function isBlobURL( key ) {
try {
const urlString = key.slice( key.indexOf( ':' ) + 1 ); // remove type identifier
const url = new URL( urlString );
return url.protocol === 'blob:';
} catch ( e ) {
// If the string is not a valid URL, it throws an error
return false;
}
}
export { Cache };