3d-tiles-renderer
Version:
https://github.com/AnalyticalGraphicsInc/3d-tiles/tree/master/specification
83 lines (50 loc) • 2.11 kB
JavaScript
import { MeshFeatures } from './metadata/classes/MeshFeatures.js';
const EXT_NAME = 'EXT_mesh_features';
function forEachPrimitiveExtension( scene, parser, callback ) {
scene.traverse( c => {
if ( parser.associations.has( c ) ) {
// check if this object has extension references
const { meshes, primitives } = parser.associations.get( c );
const primitive = parser.json.meshes[ meshes ]?.primitives[ primitives ];
if ( primitive && primitive.extensions && primitive.extensions[ EXT_NAME ] ) {
callback( c, primitive.extensions[ EXT_NAME ] );
}
}
} );
}
/**
* GLTF loader plugin that parses the {@link https://github.com/CesiumGS/glTF/tree/3d-tiles-next/extensions/2.0/Vendor/EXT_mesh_features EXT_mesh_features}
* extension and attaches a `MeshFeatures` instance to `mesh.userData.meshFeatures` on
* each primitive. Register with a `GLTFLoader` via
* `loader.register( () => new GLTFMeshFeaturesExtension() )`.
* @param {Object} parser The GLTF parser instance provided by the loader.
*/
export class GLTFMeshFeaturesExtension {
constructor( parser ) {
this.parser = parser;
this.name = EXT_NAME;
}
async afterRoot( { scene, parser } ) {
// skip if the extension is not present
const extensionsUsed = parser.json.extensionsUsed;
if ( ! extensionsUsed || ! extensionsUsed.includes( EXT_NAME ) ) {
return;
}
// get fetch the relevant textures are loaded
const textureCount = parser.json.textures?.length || 0;
const promises = new Array( textureCount ).fill( null );
forEachPrimitiveExtension( scene, parser, ( child, { featureIds } ) => {
featureIds.forEach( info => {
if ( info.texture && promises[ info.texture.index ] === null ) {
const index = info.texture.index;
promises[ index ] = parser.loadTexture( index );
}
} );
} );
// initialize mesh features on each primitive
const textures = await Promise.all( promises );
forEachPrimitiveExtension( scene, parser, ( child, extension ) => {
child.userData.meshFeatures = new MeshFeatures( child.geometry, textures, extension );
} );
}
}