AnimToolkit
Everything for animated characters: playing clips, blending them with graphs, and editing them in the editor.
This doc is a work in progress.
AnimToolkit includes two modules. Animation, which your game uses at runtime, and AnimationEditor, which only the editor loads, for in-editor tooling.
Without the plugin, skinned meshes still import and draw in their bind pose, and clips still import as assets. They just don't play.
Playing a clip
Add an AnimationComponent to an entity with a skinned mesh. Pick a clip under Animation, and tick PlayOnStart to have it play when the game starts.
| Setting | What it does |
|---|---|
| Animation | The clip to play. The list only shows clips that fit the entity's skeleton. |
| PlayOnStart | Start playing when the game starts. |
| LoopMode | Whether the clip plays once or loops. |
| Speed | Playback speed. 1 is normal. |
| Graph | An animation graph to run instead of a single clip. See below. |
Importing a model with animations adds the AnimationComponent for you, set to the first clip. You can turn that off in the import settings with AddAnimationComponent.
If a clip was made for a different skeleton, or there's no skeleton at all, the Inspector shows a warning.
Animation graphs
An animation graph decides which pose a character shows. Instead of switching clips by hand, you build a graph once, then drive it with a few parameters like Speed or Jump from your game.
Create one from Assets › Add... › Animation Graph. Double-click a graph in Assets to open it.
Nodes
A graph is a set of nodes that each produce a pose. Wire them together and mark one as the output.
| Node | What it does |
|---|---|
| Clip | Plays a clip, with a play rate, looping and a start offset. |
| Blend1D | Blends clips placed along one parameter, like idle, walk and run on speed. |
| Blend2D | Blends clips over two parameters, like forward and sideways velocity. |
| Layer | Plays one pose over another, only on the bones in a bone mask. |
| Additive | Adds a pose on top of a base pose. |
| ChainTwist | Twists a chain of bones, for aiming. |
| Slot | A place for gameplay to play a one-off clip, like an emote, over the graph. |
| FootIK | Plants the feet on the ground. |
| StateMachine | Moves between states, each with its own pose. |
Clips in a sync group share their phase, so blended walk and run cycles keep their feet in step.
State machines
Double-click a StateMachine node to open it. States are boxes and transitions are arrows. Right-click a state and pick Make Transition, then click the state it leads to.
Each transition has a duration, a blend curve, a priority, and conditions that read like sentences: Speed > 0.5, Jump is triggered, time in state >= 0.3s.
Parameters
The Parameters panel lists the values your game sets. They can be floats, bools, triggers or vectors. While you're editing, drag a value and watch the preview character blend.
Character models
CharacterModelComponent drives a character from its character controller. It works out speed, direction, whether it's in the air and so on, and feeds them to the graph. It also handles which way the character faces, turn-in-place steps and aiming.
By default it runs the built-in HumanoidMotionMatching graph, so a humanoid character animates with no setup. To use your own, set Graph.
| Setting | What it does |
|---|---|
| Graph | The animation graph to run. |
| FacingMode, TurnSharpness | Which way the body faces, and how quickly it turns to it. |
| AlignToCapsule, ModelOffset | Where the model sits inside the character controller's capsule. |
| FootIK | Plants the feet on uneven ground. FootProbeHeight, FootProbeDepth and FootIKSmoothing tune it. |
| ApplyRootMotion | Moves the character with the motion baked into the clip. |
Humanoids and retargeting
A skeleton can be marked as a humanoid by mapping its bones to standard slots like hips, spine and the arm and leg chains. The editor can map common rigs for you.
Once two skeletons are mapped, a clip made for one plays on the other. Rotations carry over bone by bone, and the hips movement is scaled to fit the new character's height.
Bone attachments
Put a BoneAttachmentComponent on an entity to make it follow a bone or socket of another character, like a sword in a hand. Sockets are named points on a skeleton, with an offset from their bone.
Using it from the editor
Editing animation
Right-click an animated entity and pick Edit Animation, or double-click a skeleton or clip in Assets. The editor opens a preview of the character:
- the hierarchy shows its bones, and you can add sockets to them;
- a timeline bar under the viewport plays the clip and lets you scrub and add markers;
- Show Bones in the tools menu draws the skeleton in the viewport.
Make your changes, then Apply to save them or Revert to throw them away.
Editing a graph
Right-click an entity and pick Edit Animation Graph, or double-click a graph in Assets. The graph opens in the bottom dock beside Assets and Console, with the viewport and preview character above it.
- Press Space on the canvas to search for a node to add.
- Select a node to edit its settings in the main Inspector.
- Press Home to frame the whole graph.
Graphs that come with the engine are read-only. Use Copy to Project to get an editable copy that's assigned to your character.
Debugging while playing
On a CharacterModelComponent or AnimationComponent, Open Graph attaches the graph to the running character. The current state, running transitions and node weights light up as you play, and the Parameters panel shows live values.
- Picking which character to debug
- Opening a new graph as soon as it's created