import ModelViewerElementBase, { Vector3D } from '../model-viewer-base.js'; import { Constructor } from '../utilities.js'; export declare type RevealAttributeValue = 'auto' | 'manual'; export declare type LoadingAttributeValue = 'auto' | 'lazy' | 'eager'; export declare const POSTER_TRANSITION_TIME = 300; export declare const PROGRESS_BAR_UPDATE_THRESHOLD = 100; export declare const $defaultProgressBarElement: unique symbol; export declare const $posterContainerElement: unique symbol; export declare const $defaultPosterElement: unique symbol; export declare interface LoadingInterface { poster: string | null; reveal: RevealAttributeValue; loading: LoadingAttributeValue; readonly loaded: boolean; readonly modelIsVisible: boolean; dismissPoster(): void; showPoster(): void; getDimensions(): Vector3D; getBoundingBoxCenter(): Vector3D; } export declare interface LoadingStaticInterface { dracoDecoderLocation: string; ktx2TranscoderLocation: string; meshoptDecoderLocation: string; mapURLs(callback: (url: string) => string): void; } export interface ModelViewerGlobalConfig { dracoDecoderLocation?: string; ktx2TranscoderLocation?: string; meshoptDecoderLocation?: string; powerPreference?: string; } /** * LoadingMixin implements features related to lazy loading, as well as * presentation details related to the pre-load / pre-render presentation of a * * * This mixin implements support for models with DRACO-compressed meshes. * The DRACO decoder will be loaded on-demand if a glTF that uses the DRACO mesh * compression extension is encountered. * * By default, the DRACO decoder will be loaded from a Google CDN. It is * possible to customize where the decoder is loaded from by defining a global * configuration option for `` like so: * * ```html * * ``` * * Note that the above configuration strategy must be performed *before* the * first `` element is created in the browser. The configuration * can be done anywhere, but the easiest way to ensure it is done at the right * time is to do it in the `` of the HTML document. This is the * recommended way to set the location because it is most compatible with * scenarios where the `` library is lazily loaded. * * If you absolutely have to set the DRACO decoder location *after* the first * `` element is created, you can do it this way: * * ```html * * ``` * * Note that the above configuration approach will not work until *after* * `` is defined in the browser. Also note that this configuration * *must* be set *before* the first DRACO model is fully loaded. * * It is recommended that users who intend to take advantage of DRACO mesh * compression consider whether or not it is acceptable for their use case to * have code side-loaded from a Google CDN. If it is not acceptable, then the * location must be customized before loading any DRACO models in order to cause * the decoder to be loaded from an alternative, acceptable location. */ export declare const LoadingMixin: >(ModelViewerElement: T) => { new (...args: any[]): LoadingInterface; prototype: LoadingInterface; } & LoadingStaticInterface & T;