<!DOCTYPE html>
<html lang="en">
<head>
<title>three.js webgl - additive animation - skinning</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
<link type="text/css" rel="stylesheet" href="main.css">
<style>
a {
color: blue;
}
.control-inactive button {
color: #888;
}
</style>
</head>
<body>
<div id="container"></div>
<div id="info">
<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - Skeletal Additive Animation Blending
(model from <a href="https://www.mixamo.com/" target="_blank" rel="noopener">mixamo.com</a>)<br/>
</div>
<script type="importmap">
{
"imports": {
"three": "../build/three.module.js",
"three/addons/": "./jsm/"
}
}
</script>
<script type="module">
import * as THREE from 'three';
import Stats from 'three/addons/libs/stats.module.js';
import { GUI } from 'three/addons/libs/lil-gui.module.min.js';
import { OrbitControls } from 'three/addons/controls/OrbitControls.js';
import { GLTFLoader } from 'three/addons/loaders/GLTFLoader.js';
let scene, renderer, camera, stats;
let model, skeleton, mixer, clock;
const crossFadeControls = [];
let currentBaseAction = 'idle';
const allActions = [];
const baseActions = {
idle: { weight: 1 },
walk: { weight: 0 },
run: { weight: 0 }
};
const additiveActions = {
sneak_pose: { weight: 0 },
sad_pose: { weight: 0 },
agree: { weight: 0 },
headShake: { weight: 0 }
};
let panelSettings, numAnimations;
init();
function init() {
const container = document.getElementById( 'container' );
clock = new THREE.Clock();
scene = new THREE.Scene();
scene.background = new THREE.Color( 0xa0a0a0 );
scene.fog = new THREE.Fog( 0xa0a0a0, 10, 50 );
const hemiLight = new THREE.HemisphereLight( 0xffffff, 0x8d8d8d, 3 );
hemiLight.position.set( 0, 20, 0 );
scene.add( hemiLight );
const dirLight = new THREE.DirectionalLight( 0xffffff, 3 );
dirLight.position.set( 3, 10, 10 );
dirLight.castShadow = true;
dirLight.shadow.camera.top = 2;
dirLight.shadow.camera.bottom = - 2;
dirLight.shadow.camera.left = - 2;
dirLight.shadow.camera.right = 2;
dirLight.shadow.camera.near = 0.1;
dirLight.shadow.camera.far = 40;
scene.add( dirLight );
// ground
const mesh = new THREE.Mesh( new THREE.PlaneGeometry( 100, 100 ), new THREE.MeshPhongMaterial( { color: 0xcbcbcb, depthWrite: false } ) );
mesh.rotation.x = - Math.PI / 2;
mesh.receiveShadow = true;
scene.add( mesh );
const loader = new GLTFLoader();
loader.load( 'models/gltf/Xbot.glb', function ( gltf ) {
model = gltf.scene;
scene.add( model );
model.traverse( function ( object ) {
if ( object.isMesh ) object.castShadow = true;
} );
skeleton = new THREE.SkeletonHelper( model );
skeleton.visible = false;
scene.add( skeleton );
const animations = gltf.animations;
mixer = new THREE.AnimationMixer( model );
numAnimations = animations.length;
for ( let i = 0; i !== numAnimations; ++ i ) {
let clip = animations[ i ];
const name = clip.name;
if ( baseActions[ name ] ) {
const action = mixer.clipAction( clip );
activateAction( action );
baseActions[ name ].action = action;
allActions.push( action );
} else if ( additiveActions[ name ] ) {
// Make the clip additive and remove the reference frame
THREE.AnimationUtils.makeClipAdditive( clip );
if ( clip.name.endsWith( '_pose' ) ) {
clip = THREE.AnimationUtils.subclip( clip, clip.name, 2, 3, 30 );
}
const action = mixer.clipAction( clip );
activateAction( action );
additiveActions[ name ].action = action;
allActions.push( action );
}
}
createPanel();
renderer.setAnimationLoop( animate );
} );
renderer = new THREE.WebGLRenderer( { antialias: true } );
renderer.setPixelRatio( window.devicePixelRatio );
renderer.setSize( window.innerWidth, window.innerHeight );
renderer.shadowMap.enabled = true;
container.appendChild( renderer.domElement );
// camera
camera = new THREE.PerspectiveCamera( 45, window.innerWidth / window.innerHeight, 1, 100 );
camera.position.set( - 1, 2, 3 );
const controls = new OrbitControls( camera, renderer.domElement );
controls.enablePan = false;
controls.enableZoom = false;
controls.target.set( 0, 1, 0 );
controls.update();
stats = new Stats();
container.appendChild( stats.dom );
window.addEventListener( 'resize', onWindowResize );
}
function createPanel() {
const panel = new GUI( { width: 310 } );
const folder1 = panel.addFolder( 'Base Actions' );
const folder2 = panel.addFolder( 'Additive Action Weights' );
const folder3 = panel.addFolder( 'General Speed' );
panelSettings = {
'modify time scale': 1.0
};
const baseNames = [ 'None', ...Object.keys( baseActions ) ];
for ( let i = 0, l = baseNames.length; i !== l; ++ i ) {
const name = baseNames[ i ];
const settings = baseActions[ name ];
panelSettings[ name ] = function () {
const currentSettings = baseActions[ currentBaseAction ];
const currentAction = currentSettings ? currentSettings.action : null;
const action = settings ? settings.action : null;
if ( currentAction !== action ) {
prepareCrossFade( currentAction, action, 0.35 );
}
};
crossFadeControls.push( folder1.add( panelSettings, name ) );
}
for ( const name of Object.keys( additiveActions ) ) {
const settings = additiveActions[ name ];
panelSettings[ name ] = settings.weight;
folder2.add( panelSettings, name, 0.0, 1.0, 0.01 ).listen().onChange( function ( weight ) {
setWeight( settings.action, weight );
settings.weight = weight;
} );
}
folder3.add( panelSettings, 'modify time scale', 0.0, 1.5, 0.01 ).onChange( modifyTimeScale );
folder1.open();
folder2.open();
folder3.open();
crossFadeControls.forEach( function ( control ) {
control.setInactive = function () {
control.domElement.classList.add( 'control-inactive' );
};
control.setActive = function () {
control.domElement.classList.remove( 'control-inactive' );
};
const settings = baseActions[ control.property ];
if ( ! settings || ! settings.weight ) {
control.setInactive();
}
} );
}
function activateAction( action ) {
const clip = action.getClip();
const settings = baseActions[ clip.name ] || additiveActions[ clip.name ];
setWeight( action, settings.weight );
action.play();
}
function modifyTimeScale( speed ) {
mixer.timeScale = speed;
}
function prepareCrossFade( startAction, endAction, duration ) {
// If the current action is 'idle', execute the crossfade immediately;
// else wait until the current action has finished its current loop
if ( currentBaseAction === 'idle' || ! startAction || ! endAction ) {
executeCrossFade( startAction, endAction, duration );
} else {
synchronizeCrossFade( startAction, endAction, duration );
}
// Update control colors
if ( endAction ) {
const clip = endAction.getClip();
currentBaseAction = clip.name;
} else {
currentBaseAction = 'None';
}
crossFadeControls.forEach( function ( control ) {
const name = control.property;
if ( name === currentBaseAction ) {
control.setActive();
} else {
control.setInactive();
}
} );
}
function synchronizeCrossFade( startAction, endAction, duration ) {
mixer.addEventListener( 'loop', onLoopFinished );
function onLoopFinished( event ) {
if ( event.action === startAction ) {
mixer.removeEventListener( 'loop', onLoopFinished );
executeCrossFade( startAction, endAction, duration );
}
}
}
function executeCrossFade( startAction, endAction, duration ) {
// Not only the start action, but also the end action must get a weight of 1 before fading
// (concerning the start action this is already guaranteed in this place)
if ( endAction ) {
setWeight( endAction, 1 );
endAction.time = 0;
if ( startAction ) {
// Crossfade with warping
startAction.crossFadeTo( endAction, duration, true );
} else {
// Fade in
endAction.fadeIn( duration );
}
} else {
// Fade out
startAction.fadeOut( duration );
}
}
// This function is needed, since animationAction.crossFadeTo() disables its start action and sets
// the start action's timeScale to ((start animation's duration) / (end animation's duration))
function setWeight( action, weight ) {
action.enabled = true;
action.setEffectiveTimeScale( 1 );
action.setEffectiveWeight( weight );
}
function onWindowResize() {
camera.aspect = window.innerWidth / window.innerHeight;
camera.updateProjectionMatrix();
renderer.setSize( window.innerWidth, window.innerHeight );
}
function animate() {
// Render loop
for ( let i = 0; i !== numAnimations; ++ i ) {
const action = allActions[ i ];
const clip = action.getClip();
const settings = baseActions[ clip.name ] || additiveActions[ clip.name ];
settings.weight = action.getEffectiveWeight();
}
// Get the time elapsed since the last frame, used for mixer update
const mixerUpdateDelta = clock.getDelta();
// Update the animation mixer, the stats panel, and render this frame
mixer.update( mixerUpdateDelta );
renderer.render( scene, camera );
stats.update();
}
</script>
</body>
</html>