afk.ai/Auto-rig/Fish and sharks
Auto-rig a fish or shark with AI
Upload a fish, shark or whale and afk.ai fits a 33-joint skeleton: an eight-segment tail for a smooth swim, two pairs of fins and a jaw that opens. It swims and bites in the preview, and downloads as a GLB.
Before is the sample model as it's uploaded: a mesh with no bones. After is the same fish on afk.ai's skeleton, playing its animations.
How it works
- 1
Upload
Drop in your fish as a GLB, a self-contained glTF or an FBX. Sign in with Google; it's free.
- 2
The AI finds its body
An AI reads the mesh and works out where everything is. On a good graphics card it runs right in your browser; otherwise the cloud rigger does it.
- 3
Skeleton and skin
afk.ai fits its fish skeleton to what the AI found and weights the skin, so the mesh bends at the joints.
- 4
Animate and export
Preview every animation on your model, then download one GLB with the skeleton, skin weights and all of the animations.
What the fish rig includes
Fish, sharks and whales: a long tail, two pairs of fins and a jaw.
Skeleton: 33 joints
- Head, neck and an opening jaw
- An eight-segment tail
- Two front fins and two back fins, three segments each
6 animations
Bite, Dead Floating, Hit, Idle, Swim Horizontal, Swim Vertical.
Download the rigged shark (.glb, 0.5 MB)The sample above with its skeleton and all 6 animations. CC0: use it for anything.
Models that rig best
- A fish lying straight, fins out, fits best.
- When afk.ai asks what it is, pick Fish, for sharks and whales too.
- One fish per file.
Use your rigged fish in Unity, Unreal, Godot or Blender
Unity 6
- Open Window > Package Manager, click +, choose Add package by name and enter com.unity.cloud.gltfast (glTFast).
- Drag the .glb into Assets. It becomes a prefab with the mesh, skeleton and one Animation Clip per animation.
- Create an Animator Controller, drag the clips into it and assign it to the Animator on the prefab.
- Prefer FBX? Export one from Blender, then in Unity set Rig > Animation Type to Generic (creatures aren't Humanoid avatars) and click Apply.
Unreal Engine 5
- Drag the .glb into the Content Browser (or +Add > Import). Unreal 5.1 and later import glTF natively.
- Click Import in the options dialog. You get a Skeletal Mesh, its Skeleton, a Physics Asset and one Animation Sequence per animation.
- Creatures keep their own skeleton, so there's nothing to retarget to the mannequin.
Godot 4
- Copy the .glb into your project folder. Godot imports it as a scene with a Skeleton3D and an AnimationPlayer holding every animation.
- For cycles like walks and idles, double-click the .glb, select the animation, set Loop Mode to Linear and click Reimport.
- Instance the scene and play one: $AnimationPlayer.play("Bite").
Blender
- File > Import > glTF 2.0 (.glb/.gltf), and pick the file.
- The mesh comes in on its armature, with the first animation active: scrub the timeline to play it.
- The other animations are on NLA tracks named after them. Click a track's star (Solo) to play it.
Questions
›Does it work for whales and dolphins?
afk.ai uses the fish skeleton for fish, sharks and whales: a long tail, two pairs of fins and a jaw.
›Which animations are included?
Two swims, Idle, Bite, Hit and Dead Floating. All of them are in the download.
›Is it free for commercial use?
Yes. Your model stays yours and the animations are CC0.
›Is afk.ai free?
Yes. Rigging, the animations and the GLB export are free. You sign in with Google, and the site is supported by ads.
›What do I need to run it?
A computer with Chrome or Edge. With a decent graphics card the AI runs in your browser (the first rig downloads the 1.1 GB AI model once). On phones and weaker computers, afk.ai offers its cloud rigger instead.