nanogl-gltf/lib/elements/Animation.js

gltf loader

import GltfTypes from '../types/GltfTypes';
/**
 * The Animation element contains the data to animate a node, linking with samplers and channels.
 */
export default class Animation {
    constructor() {
        this.gltftype = GltfTypes.ANIMATION;
        /**
         * Duration of the animation
         */
        this.duration = 0;
    }
    /**
     * Parse the Animation data, creates the samplers and channels.
     *
     * Is async as it needs to wait for all the samplers and channels to be created.
     * @param gltfLoader GLTFLoader to use
     * @param data Data to parse
     */
    async parse(gltfLoader, data) {
        const samplerPromises = data.samplers.map((data) => gltfLoader._loadElement(data));
        this.samplers = await Promise.all(samplerPromises);
        for (const sampler of this.samplers) {
            this.duration = Math.max(sampler.maxTime);
        }
        const channelPromises = data.channels.map((data) => gltfLoader._loadElement(data));
        this.channels = await Promise.all(channelPromises);
    }
    /**
     * Evaluate the animation at a given time, updating the nodes properties.
     * It evaluates each channel, which in turn evaluates the sampler and apply the value to the node.
     * @param t Time to evaluate the animation at
     */
    evaluate(t) {
        for (const channel of this.channels) {
            channel.evaluate(t);
        }
    }
    getChannel(i) {
        return this.channels[i];
    }
    getSampler(i) {
        return this.samplers[i];
    }
}