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- <h1>[name]</h1>
- <h2>Overview</h2>
- <p class="desc">
- Within the three.js animation system you can animate various properties of your models:
- the bones of a [page:SkinnedMesh skinned and rigged model], morph targets, different material properties
- (colors, opacity, booleans), visibility and transforms. The animated properties can be faded in,
- faded out, crossfaded and warped. The weight and time scales of different simultaneous
- animations on the same object as well as on different objects can be changed
- independently. Various animations on the same and on different objects can be
- synchronized.<br /><br />
- To achieve all this in one homogeneous system, the three.js animation system
- [link:https://github.com/mrdoob/three.js/issues/6881 has completely changed in 2015]
- (beware of outdated information!), and it has now an architecture similar to
- Unity/Unreal Engine 4. This page gives a short overview of the main components of the
- system and how they work together.
- </p>
- <h3>Animation Clips</h3>
- <p class="desc">
- If you have successfully imported an animated 3D object (it doesn't matter if it has
- bones or morph targets or both) — for example exporting it from Blender with the
- [link:https://github.com/KhronosGroup/glTF-Blender-IO glTF Blender exporter] and
- loading it into a three.js scene using [page:GLTFLoader] — one of the response fields
- should be an array named "animations", containing the [page:AnimationClip AnimationClips]
- for this model (see a list of possible loaders below).<br /><br />
- Each `AnimationClip` usually holds the data for a certain activity of the object. If the
- mesh is a character, for example, there may be one AnimationClip for a walkcycle, a second
- for a jump, a third for sidestepping and so on.
- </p>
- <h3>Keyframe Tracks</h3>
- <p class="desc">
- Inside of such an `AnimationClip` the data for each animated property are stored in a
- separate [page:KeyframeTrack]. Assuming a character object has a [page:Skeleton skeleton],
- one keyframe track could store the data for the position changes of the lower arm bone
- over time, a different track the data for the rotation changes of the same bone, a third
- the track position, rotation or scaling of another bone, and so on. It should be clear,
- that an AnimationClip can be composed of lots of such tracks.<br /><br />
- Assuming the model has morph targets (for example one morph
- target showing a friendly face and another showing an angry face), each track holds the
- information as to how the [page:Mesh.morphTargetInfluences influence] of a certain morph
- target changes during the performance of the clip.
- </p>
- <h3>Animation Mixer</h3>
- <p class="desc">
- The stored data forms only the basis for the animations - actual playback is controlled by
- the [page:AnimationMixer]. You can imagine this not only as a player for animations, but
- as a simulation of a hardware like a real mixer console, which can control several animations
- simultaneously, blending and merging them.
- </p>
- <h3>Animation Actions</h3>
- <p class="desc">
- The `AnimationMixer` itself has only very few (general) properties and methods, because it
- can be controlled by the [page:AnimationAction AnimationActions]. By configuring an
- `AnimationAction` you can determine when a certain `AnimationClip` shall be played, paused
- or stopped on one of the mixers, if and how often the clip has to be repeated, whether it
- shall be performed with a fade or a time scaling, and some additional things, such crossfading
- or synchronizing.
- </p>
- <h3>Animation Object Groups</h3>
- <p class="desc">
- If you want a group of objects to receive a shared animation state, you can use an
- [page:AnimationObjectGroup].
- </p>
- <h3>Supported Formats and Loaders</h3>
- <p class="desc">
- Note that not all model formats include animation (OBJ notably does not), and that only some
- three.js loaders support [page:AnimationClip AnimationClip] sequences. Several that <i>do</i>
- support this animation type:
- </p>
- <ul>
- <li>[page:ObjectLoader THREE.ObjectLoader]</li>
- <li>THREE.BVHLoader</li>
- <li>THREE.ColladaLoader</li>
- <li>THREE.FBXLoader</li>
- <li>[page:GLTFLoader THREE.GLTFLoader]</li>
- <li>THREE.MMDLoader</li>
- </ul>
- <p class="desc">
- Note that 3ds max and Maya currently can't export multiple animations (meaning animations which are not
- on the same timeline) directly to a single file.
- </p>
- <h2>Example</h2>
- <code>
- let mesh;
- // Create an AnimationMixer, and get the list of AnimationClip instances
- const mixer = new THREE.AnimationMixer( mesh );
- const clips = mesh.animations;
- // Update the mixer on each frame
- function update () {
- mixer.update( deltaSeconds );
- }
- // Play a specific animation
- const clip = THREE.AnimationClip.findByName( clips, 'dance' );
- const action = mixer.clipAction( clip );
- action.play();
- // Play all animations
- clips.forEach( function ( clip ) {
- mixer.clipAction( clip ).play();
- } );
- </code>
- </body>
- </html>
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