DragControls with GLTF Animations

GLTF models exported with animations, often don't work with the DragControls, so one approach to solve the problem, is to create a secondary object, such as a cube, and bind the DragControls to that instead. Then adjust the position of your model group to the new position of the cube being dragged.

In this example, you can drag the animated GLTF model using the DragControls.

Start Scripts

./src/server/server.ts

import express from "express"
import path from "path"
import http from "http"

const port: number = 3000

class App {
    private server: http.Server
    private port: number

    constructor(port: number) {
        this.port = port
        const app = express()
        app.use(express.static(path.join(__dirname, '../client')))
        app.use('/build/three.module.js', express.static(path.join(__dirname, '../../node_modules/three/build/three.module.js')))
        app.use('/jsm/controls/OrbitControls', express.static(path.join(__dirname, '../../node_modules/three/examples/jsm/controls/OrbitControls.js')))
        app.use('/jsm/loaders/GLTFLoader', express.static(path.join(__dirname, '../../node_modules/three/examples/jsm/loaders/GLTFLoader.js')))
        app.use('/jsm/libs/stats.module', express.static(path.join(__dirname, '../../node_modules/three/examples/jsm/libs/stats.module.js')))
        app.use('/jsm/controls/DragControls', express.static(path.join(__dirname, '../../node_modules/three/examples/jsm/controls/DragControls.js')))

        this.server = new http.Server(app);
    }

    public Start() {
        this.server.listen(this.port, () => {
            console.log( `Server listening on port ${this.port}.` )
        })
    }
}

new App(port).Start()

./src/client/client.ts

import * as THREE from '/build/three.module.js'
import { OrbitControls } from '/jsm/controls/OrbitControls'
import { GLTFLoader } from '/jsm/loaders/GLTFLoader'
import Stats from '/jsm/libs/stats.module'
import { DragControls } from '/jsm/controls/DragControls'

const scene: THREE.Scene = new THREE.Scene()
const axesHelper = new THREE.AxesHelper(5)
scene.add(axesHelper)

var light1 = new THREE.PointLight();
light1.position.set(2.5, 2.5, 2.5)
light1.castShadow = true
scene.add(light1);

var light2 = new THREE.PointLight();
light2.position.set(-2.5, 2.5, 2.5)
light2.castShadow = true
scene.add(light2);


const camera: THREE.PerspectiveCamera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.01, 1000)
camera.position.set(0.8, 1.4, 1.0)

const renderer: THREE.WebGLRenderer = new THREE.WebGLRenderer()
renderer.setSize(window.innerWidth, window.innerHeight)
renderer.shadowMap.enabled = true
document.body.appendChild(renderer.domElement)

const orbitControls = new OrbitControls(camera, renderer.domElement)
orbitControls.screenSpacePanning = true
orbitControls.target.set(0, 1, 0)

const sceneMeshes: THREE.Mesh[] = new Array()
let boxHelper: THREE.BoxHelper

const dragControls = new DragControls(sceneMeshes, camera, renderer.domElement)
dragControls.addEventListener("hoveron", function (event) {
    boxHelper.visible = true
    orbitControls.enabled = false
});
dragControls.addEventListener("hoveroff", function (event) {
    boxHelper.visible = false
    orbitControls.enabled = true
});
dragControls.addEventListener("drag", function (event) {
    event.object.position.y = 0
});
dragControls.addEventListener('dragstart', function (event) {
    boxHelper.visible = true
    orbitControls.enabled = false
})
dragControls.addEventListener('dragend', function (event) {
    boxHelper.visible = false
    orbitControls.enabled = true
})

const planeGeometry: THREE.PlaneGeometry = new THREE.PlaneGeometry(25, 25)
const texture = new THREE.TextureLoader().load("img/grid.png")
const plane: THREE.Mesh = new THREE.Mesh(planeGeometry, new THREE.MeshPhongMaterial({ map: texture }))
plane.rotateX(-Math.PI / 2)
plane.receiveShadow = true
scene.add(plane)

let mixer: THREE.AnimationMixer
let modelReady = false;
const gltfLoader: GLTFLoader = new GLTFLoader();
let modelGroup: THREE.Group
let modelDragBox: THREE.Mesh

gltfLoader.load(
    'models/eve@punching.glb',
    (gltf) => {
        gltf.scene.traverse(function (child) {
            if (child instanceof THREE.Group) {
                modelGroup = child
            }
            if ((<THREE.Mesh>child).isMesh) {
                child.castShadow = true
                child.frustumCulled = false;
                (child as THREE.Mesh).geometry.computeVertexNormals()
            }
        });

        mixer = new THREE.AnimationMixer(gltf.scene);
        mixer.clipAction((gltf as any).animations[0]).play()


        modelDragBox = new THREE.Mesh(new THREE.BoxGeometry(.5, 1.3, .5), new THREE.MeshBasicMaterial({ transparent: true, opacity: 0 }))
        modelDragBox.geometry.translate(0, .65, 0)
        scene.add(modelDragBox)
        sceneMeshes.push(modelDragBox);

        boxHelper = new THREE.BoxHelper(modelDragBox, 0xffff00 )
        boxHelper.visible = false
        scene.add(boxHelper)

        scene.add(gltf.scene)

        modelReady = true
    },
    (xhr) => {
        console.log((xhr.loaded / xhr.total * 100) + '% loaded')
    },
    (error) => {
        console.log(error);
    }
)

window.addEventListener('resize', onWindowResize, false)
function onWindowResize() {
    camera.aspect = window.innerWidth / window.innerHeight
    camera.updateProjectionMatrix()
    renderer.setSize(window.innerWidth, window.innerHeight)
    render()
}

const stats = Stats()
document.body.appendChild(stats.dom)

const clock: THREE.Clock = new THREE.Clock()

var animate = function () {
    requestAnimationFrame(animate)

    orbitControls.update()

    if (modelReady) {
        mixer.update(clock.getDelta());
        modelGroup.position.copy(modelDragBox.position)
        boxHelper.update()
    }

    render()

    stats.update()
};

function render() {
    renderer.render(scene, camera)
}
animate();