#Rigging light fixtures for EVT3D
Name four nodes, nest them in order, and your fixture model pans, tilts, and lights like a real unit.
EVT3D's Light Shop can load your own fixture models — a Leko, a moving head, an LED batten, the specific unit your shop actually hangs — and drive them like the built-in parametric fixtures: pan and tilt controls, a real spotlight with a volumetric beam and lens flare, and a lens face that glows hot in the center and fades to the beam color at the rim.
None of that comes from materials or clever geometry. It comes from four named nodes nested in the right order. Get the chain right and the fixture articulates, aims, and lights with nothing to fix afterward. This tutorial is how to set that chain up in any 3D package that exports FBX or GLB — Blender, 3ds Max, Cinema 4D, Maya, Unity, doesn't matter.
#The rig chain
Every fixture is one chain, each part a child of the one above:
FixtureName ← root (the display name — anything you like)
FixtureName_Base ← the static mount: clamp / floor plate. Never moves.
FixtureName_Yoke ← pans (spins about the vertical axis)
FixtureName_Head ← tilts + carries the beam (the barrel / lamp body)
FixtureName_Lens ← the lens face — beam origin + the lit-lens shader
That's the whole contract. EVT3D reads the node names, figures out which part is which, and rotates each one about its own pivot. Everything below is just getting those four parts split, named, pivoted, and oriented correctly.
#Step 1 — Split the parts
Model (or cut) the fixture into separate objects along its real articulation lines. The classic mistake: modeling the pipe clamp and the yoke fork as one object. Do that, and when the fixture pans, the clamp spins around the pipe with it — it can't not, they're one mesh.
The rule for where to cut: anything that moves together is one part; anything that stays behind is the part above it.
- The clamp or floor plate that grips the pipe / sits on the ground → Base
- The fork that spins on the pan bolt → Yoke
- The body that rocks on the tilt axle (and everything bolted to it) → Head
- The aperture face at the front → Lens (a separate mesh — see Step 4)
#Step 2 — Name the nodes
Suffix each node with its role. FixtureName_Base, FixtureName_Yoke, FixtureName_Head, FixtureName_Lens — for example RobePointe_Base, RobePointe_Yoke, RobePointe_Head, RobePointe_Lens.
Matching is case-insensitive and keys on the last word of the name, so these synonyms also work:
| Canonical | Also accepted |
|---|---|
_Base | foot, floor, bracket, clamp, hook, hanger, mount, stand |
_Yoke | fork, arm, gimbal |
_Head | body, barrel, can, lamp, par |
_Lens | optic, source, emit, aim, beam |
Use the canonical four. The synonyms are a safety net, not the standard.
The root node's name is free — call it ParCan or MovingHead and EVT3D knows it's the display wrapper, not a rig part.
#Step 3 — Place the pivots
EVT3D rotates each node about its own local origin, so the origins must sit on the fixture's real axes:
- Yoke origin → on the vertical pan bolt (the axis the fork spins around).
- Head origin → on the horizontal tilt axle (the line through the two yoke side-knobs).
- Base origin → the mount contact point (where it grips the pipe or meets the floor).
Then set the rest pose and scale:
- Author the fixture standing: upright, +Y up, base at the world origin (mount contact at Y = 0), head above.
- At rest, the beam aims straight out −Z (that's "forward" in EVT3D).
- Real-world scale, in meters. A Leko is about 0.6 m long, not 60.
Author one standing pose only — EVT3D handles the rest. Floor and stand mounts use the model as-authored; hanging it from pipe or truss flips it so the clamp grips up and the barrel hangs below. Don't pre-author an upside-down version.
Tip — different packages disagree about which axis is "up" and "forward" in the source scene; what matters is the exported file. Open your GLB in any glTF viewer and check: fixture upright, beam pointing away from the default camera view (−Z). If it's lying on its face, fix the export axis settings, not the model.
#Step 4 — The lens
Give the fixture a separate flat disc (or shallow cap) at the aperture, child of the Head, named FixtureName_Lens. It does two jobs:
- Beam origin and aim. The spotlight, volumetric beam, and lens flare all pin to the Lens position, and the beam direction is head-pivot → lens. With a lens node there is zero guessing about where the fixture emits or which way it points. Put the mesh's pivot at the lens center, on the optical axis.
- The lit-lens shader. EVT3D swaps the Lens material at runtime for its lens shader — a hot near-white core fading to the beam's color, what you see staring into a lit fixture. For the hotspot to land centered:
- Keep the lens a flat disc facing straight out along the beam.
- Give it planar UVs centered on the disc — center at (0.5, 0.5), rim at the edge. A default unwrap of a disc cap is usually exactly this.
- Make it its own material. The authored color barely matters (it gets replaced); a simple emissive is fine.
Multi-emitter fixtures — an LED batten, a wash with visible cells — get one lens per cell: FixtureName_Lens_01, _Lens_02, and so on, each with its own centered UVs. Each cell renders its own hotspot, and the beam originates from the center of the group.
#Step 5 — Fixtures that don't fully articulate
Not every unit has all four parts. Two reduced forms are supported:
| You author | What EVT3D does |
|---|---|
_Yoke > _Head > _Lens — no Base | The yoke is the mount (a hung PAR's U-bracket). It still pans; there's just no static piece. |
_Base > _Head > _Lens — no Yoke | Tilt-only. Pan is disabled and the base never moves. |
If in doubt, include all four — even a fixture that never really pans is nicer to aim with a working pan control.
#Step 6 — Export
- GLB is the native format. FBX works too — the upload pipeline auto-converts it — but always verify the node chain survived (open the converted preview and check the part names).
- Keep the hierarchy. Turn off any "merge meshes," "flatten," "join," or "collapse empties" export option. If the exporter fuses your four parts into one mesh, the rig is gone and there is nothing EVT3D can do to get it back.
- Draco compression is fine. Embedded textures are fine.
- One material for the whole body is fine — only the Lens needs its own.
#Step 7 — Categorize the upload
Upload the model into the Light Fixtures category. That category is what the Light Shop's Premodeled fixtures list shows (Design tab → Mode → Premodeled (model)) — categorized fixtures show up there instantly as pickable lights. The model's name is up to you.
Fastest path: that list's ⬆ Upload Fixture Model button takes the file directly (GLB, GLTF, OBJ, FBX, SKP, or zip), files it under Light Fixtures for you, and loads it straight into the studio.
Forgot the category? The 🔍 Search Library button next to it searches your whole library unfiltered, so you can still find and load the model — then set its category to Light Fixtures in the Prop Editor to keep it in the fast list.
#Pre-flight checklist
- Four nodes, nested
_Base > _Yoke > _Head > _Lens, each a child of the one above. - Base is only the static clamp/plate — nothing that should move is attached to it.
- Yoke origin on the pan bolt; Head origin on the tilt axle.
- Upright, +Y up, base at the origin, beam out −Z at rest.
- Lens is a separate flat disc at the aperture, centered UVs, its own material.
- Meters, real-world scale.
- Hierarchy preserved on export (no merge/flatten).
- Uploaded into the Light Fixtures category.
#Check your work
In the Light Shop, open the Design tab, set Mode to Premodeled (model), and load the fixture from Premodeled fixtures. The mapping panel lists what was detected — Base, Yoke, Head, Lens, each with the node it mapped to. Four named rows means the rig read exactly as you authored it; a "— (emit estimated)" on the Lens row means the lens marker didn't survive export, and EVT3D is guessing the beam origin from the head's shape. Then grab Pan (yoke) and Tilt (body) under Aim — Test Drive: the clamp should hold still, the fork should spin, the barrel should rock, and the beam should follow the lens.
For the reference version of this contract — the tables without the walk-through — see Premodeled light fixtures in the manual.