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Baked Light

Baked light works out soft shadows in corners (ambient occlusion) and light bouncing off walls once, for everything in the scene that does not move, and saves the result with the scene. A red wall tints the floor beside it, and a crate sits in a soft shadow, without any cost while you play. It looks the same on a phone, in a headset, and on the desktop next to it.

The Baked light section in Configure Scene ▸ Scene look

Baking

  1. Arrange the scene first. A bake is a snapshot of where things are now.
  2. Open Configure Scene ▸ Scene look and find Baked light.
  3. Choose a Quality (Draft, Normal or High) and press Bake light.

A progress bar shows how far it has got, and Cancel stops it at once. Nothing in the scene changes until a bake has finished. You can keep working while it runs: the bake happens in the background and never freezes the editor.

When it finishes, everyone in the session sees the baked light, it is saved with the scene, and Undo takes the whole bake off in one step.

Two sliders then tune it without baking again:

  • Bounce light — how strong the bounced light is (1 = as baked).
  • Corner shadows — how dark the ambient occlusion is.

Remove baked light takes it off again (also one Undo step).

What gets baked

Everything that does not move:

  • Left out: objects with a physics body that moves (dynamic or kinematic), objects moved by a node graph or played by an animation clip, animated characters, instanced objects, hidden objects, and anything spawned while a game runs.
  • Everything that is baked also casts onto everything else — a pillar's shadow lands on the floor.
  • The panel lists what was left out and why, for example "2 objects left out: 1 moves with physics, 1 has an animation."
  • Big, detailed scenes (a whole tavern of carved kit pieces) still fit in one lightmap: very detailed objects are laid out by their own texture coordinates. Where those overlap, the object gets the soft corner shadows but no baked light, and the panel says so. Only when even that is too much are the most detailed small props left out. They still cast shadows onto the rest, and keep their normal lighting.

The light that bounces comes from the scene's own lights (the sun, point and spot lights). Those lights and the sky still light the scene live as before, so moving objects and baked ones match. A scene with no lights bakes the corner shadows only.

When things move: "Out of date"

If you move, delete or reshape a baked object, or change the lights, an Out of date chip appears next to the button. The old bake stays until you press Bake again — move things back and the chip goes away.

Lightmap UVs

A bake needs a second set of texture coordinates that do not overlap. The app makes them for you: it uses the model's own second UV set when it has a clean one, and otherwise unwraps the object itself. Your model is never changed — the bake's coordinates live beside it and are rebuilt the same way on every device.

If an object's UVs overlap and cannot be unwrapped cleanly, it gets the corner shadows only, and the panel says so in one line.

Devices

Device Lightmap Time limit Download it shows
Desktop up to 2048 px 2 minutes up to 16 MB
Phone up to 1024 px 1 minute up to 2 MB
Headset 512 px 45 seconds up to 1 MB

A bake made on a desktop also stores a small 512 px copy, which phones and headsets show when the full map is too big for them. A bake that hits the time limit keeps what it has and says so; Bake again on a faster device for a cleaner result.

Asking an AI to bake

The Claude connector and the in-app assistant can bake too: ask it to "bake the light" once the layout is done. It uses set_look with the bake action (do: bake, status, cancel, clear or strength), asks the host first like any scene-wide look change, and can tell you when the bake is out of date.

Limits worth knowing

  • Moving objects are not baked. They are still lit live and still receive the live shadows, but they get no baked corner shadows.
  • A bake is one bounce. The light bounces once off the surfaces it hits; the sky is not baked (it stays live).
  • Objects drawn by a Shader Graph and materials that cannot take a lightmap are not baked (they still cast onto others).
  • A GLTF export does not carry the bake. Save a Scene (.tpscene) to keep it. The lightmap is saved in the scene and shows in Scene ▸ textures.
  • Scenes saved before this version open exactly as they did.