Cascadeur bridge

The Cascadeur bridge integrates Cascadeur — a physics-aware character animation tool — into Buril. The headline feature is AI keyframe assist: you pose a few extremes, Cascadeur fills the middle with physically plausible interpolation, Buril ingests the result as a Unity .anim clip.

Bridge namespace: cascadeur_* — 85 tools.

What it does

Step	Tools involved
1. Push a rigged character to Cascadeur	cascadeur_push_rig, asset_export_fbx
2. Define key poses (from chat or from a recipe)	cascadeur_set_keyframe, cascadeur_pose_apply_preset
3. Run AutoPosing / AI keyframes	cascadeur_keyframe_run (this is where Indie+ is required)
4. Apply physics interpolation	cascadeur_physics_interpolate
5. Export Alembic / FBX back to Unity	cascadeur_export_alembic, cascadeur_export_fbx
6. Convert to AnimationClip	animation_clip_from_fbx, animator_controller_add_state

Tier requirements

Cascadeur tier	Cost (vendor)	What works in the bridge
Basic (free)	$0	Manual keyframe push/pull, export, Unity round-trip. No AI features.
Indie	~$30 / month	AI keyframes, AutoPosing, physics interpolation. Full bridge feature set.
Indie+ / Pro	Higher tiers	Same Buril features as Indie + Cascadeur's own pro features.

The bridge detects your tier at startup via the Cascadeur API. If you call cascadeur_keyframe_run on a Basic license, the tool returns ok: false, error: "Cascadeur Indie+ required" and the agent falls back to manual interpolation.

Buril does not resell Cascadeur licenses — you subscribe directly with Cascadeur.

Plugin install

Cascadeur exposes a Python scripting API. The Buril plugin lives at:

Tools~/cascadeur-plugin/

To install:

1. Copy the contents of Tools~/cascadeur-plugin/ into Cascadeur's user plugin folder:
   • Windows: %APPDATA%\Cascadeur Software\Cascadeur\plugins\
   • macOS: ~/Library/Application Support/Cascadeur/plugins/
   • Linux: ~/.config/Cascadeur/plugins/
2. Restart Cascadeur.
3. The Buril plugin opens a TCP listener on 127.0.0.1:9876 (configurable).
4. Back in Unity, run cascadeur_handshake_ping to confirm.

The bridge also ships a wizard: Tools → Buril → Cascadeur Wizard that walks the install.

A round-trip in chat

Push the Player rig to Cascadeur, set the running cycle preset, run AI keyframes,
and bring back a 1-second clip into Assets/Animations/Player_Run.anim.

The cascadeur-animator specialist runs:

1. cascadeur_push_rig (target Player avatar)
2. cascadeur_pose_apply_preset (running cycle)
3. cascadeur_keyframe_run (AI fills in interpolation)
4. cascadeur_physics_interpolate
5. cascadeur_export_fbx
6. animation_clip_from_fbx

Total time: ~20-40 seconds depending on rig complexity.

Keyframe recipes

Pre-built pose recipes ship under Tools~/cascadeur-plugin/recipes/:

• idle_breathing.json — 30-frame idle with subtle chest expansion.
• running_cycle.json — 12-frame running stride.
• jump_arc.json — takeoff + apex + landing keys.
• wave_greeting.json — 24-frame waving NPC greeting.

Recipes are JSON files that map bone IDs to local rotations at each keyframe. To add your own, drop a JSON under recipes/ and re-handshake.

Two-way iteration

Pose tweaking is a back-and-forth:

You: That run looks too stiff. Make the arms swing more.
[cascadeur-animator] cascadeur_set_keyframe(arm.right, +20deg yaw)
[cascadeur-animator] cascadeur_keyframe_run
[cascadeur-animator] cascadeur_export_fbx
Buril ingests new clip → overwrites Assets/Animations/Player_Run.anim

The chat panel keeps the running Cascadeur session alive between turns — there's no need to re-push the rig.

Headless / CI

You can run Cascadeur AI keyframing in CI, but it requires:

• A Cascadeur headless license (currently Indie+ tier — confirm with Cascadeur).
• A display server (Xvfb on Linux) — Cascadeur's GUI is not fully headless yet.

The Buril CLI invocation:

buril --tool cascadeur_keyframe_run --input '{"preset":"running_cycle","frames":12}'

Common issues

Symptom	Fix
"Handshake failed"	Plugin not installed, or port 9876 occupied. Check Cascadeur's Output log.
"Indie+ required"	Subscription expired or running Basic. Either upgrade or use manual keyframing.
AI keyframes look floaty	Physics interpolation needs a mass profile. Run cascadeur_set_character_mass first.
Export FBX has flipped axes	Cascadeur's axis convention is Z-up; the bridge re-axis on export. If you skip the bridge, you'll see flipped meshes.

Licensing reminder

Cascadeur is published by Cascadeur Software. Buril does not bundle Cascadeur. Your Cascadeur subscription/EULA governs use of the application; Buril's bridge only wires Unity to your existing install.

Read next

• VRoid bridge — pose Cascadeur output onto a VRoid character.
• AI animation — for animations that don't require Cascadeur.