nanogl-gltf/lib/elements/AccessorSparseValues.js

gltf loader

import GltfTypes from "../types/GltfTypes";
import { BaseAccessor, getArrayForDataType } from "./Accessor";
import Assert from "../lib/assert";
/**
 * The AccessorSparseValues element is an Accessor that contains the new values of the vertices that are sparse.
 */
export default class AccessorSparseValues extends BaseAccessor {
    constructor() {
        super(...arguments);
        this.gltftype = GltfTypes.ACCESSOR_SPARSE_VALUES;
    }
    /**
     * Parse the AccessorSparseValues data, load the BufferView element and store only the part that is needed in _array attribute.
     *
     * Is async as it needs to wait for the BufferView to be created.
     * @param gltfLoader GLTFLoader to use
     * @param data Data to parse
     */
    async parse(gltfLoader, data) {
        var _a, _b;
        const sparseData = data.elementParent;
        const accessorData = sparseData.elementParent;
        this.byteOffset = (_a = data.byteOffset) !== null && _a !== void 0 ? _a : 0;
        this.count = sparseData.count;
        this.normalized = (_b = accessorData.normalized) !== null && _b !== void 0 ? _b : false;
        this.componentType = accessorData.componentType;
        this.type = accessorData.type;
        this.sparse = null;
        this.bufferView = await gltfLoader.getElement(GltfTypes.BUFFERVIEW, data.bufferView);
        const Arr = getArrayForDataType(this.componentType);
        if (this.bufferView.byteStride === 0) {
            this._stride = this.numComps * this.bytesPerElem;
            this._strideElem = this.numComps;
        }
        else {
            this._stride = this.bufferView.byteStride;
            this._strideElem = this._stride / Arr.BYTES_PER_ELEMENT;
            Assert.isTrue(this._strideElem === Math.round(this._strideElem));
        }
        this._array = new Arr(this.bufferView.buffer._bytes, this.byteOffset + this.bufferView.getByteOffset(), this.count * this._strideElem);
        this._valueHolder = this.createElementHolder();
        return Promise.resolve();
    }
}