This follows the basic walkthrough for World Labs Marble. It assumes you have a world you like and now need it playable.

What format should you export?

Take a mesh format your engine imports natively — glTF or FBX — rather than a proprietary scene file. glTF is the safer bet across Unity, Unreal and web viewers, and it carries materials in one file.

Export at the highest texture resolution available. Downscaling later is easy; recovering detail from an already-compressed texture is not.

Why is the scale always wrong in the engine?

Because generated worlds come in their own units, and your engine expects meters. A doorway that looks human-sized in the Marble viewer can import at ten times scale.

Fix it before doing anything else:

1. Import the mesh into a test scene with a 1-meter reference cube.
2. Scale the root object until a doorway or person-height ledge reads correctly.
3. Apply the transform so the scale is baked into vertices, not left on the node.

Unity treats 1 unit as 1 meter; Unreal treats 1 unit as 1 centimeter. That difference alone causes most “giant world” imports.

How do you handle collision?

Do not use the full generated mesh as a collider. The triangle count is enormous and the physics engine will choke. Generate a simple collider instead:

• Use a coarse convex decomposition or a box/primitive collider set for walls.
• Add an invisible floor plane for walking surfaces rather than relying on raw geometry.
• Delete geometry outside the playable area — decorative detail the player never reaches still costs collision budget.

A scene that renders fine can still drop frames purely from collision, so treat this as a required step, not an optimization.

What about lighting and materials?

Generated worlds often ship with baked-in shading in the textures. If you add real-time lights on top, the scene looks muddy — light from two sources fighting.

Either rebake lighting for your engine’s pipeline, or regenerate the world with flatter, more neutral base colors if the tool allows. Baking once in the engine gives you consistent shadows across the whole level instead of shadows frozen into texture from the original viewpoint.

When is this pipeline not worth it?

When the camera stays fixed or the environment is a backdrop behind a cutscene. In that case a rendered image or video is cheaper and looks better than a walkable mesh you have to clean up. Reserve the engine pipeline for places the player can actually explore.

Quick Summary

• Export glTF or FBX at maximum texture resolution.
• Fix scale against a 1-meter reference before anything else.
• Never use the raw mesh as a collider — build simple collision around it.
• Rebake lighting; baked-in shading fights real-time lights.
• Skip the pipeline entirely for fixed-camera backdrops — use a video instead.

It is a generation tool, not a game engine. The output quality at first is best for prototyping environments, blocking out a scene, or building background assets, not for shipping a AAA level.

How do you generate your first world?

1. Open Marble and pick an input type — text prompt, image, or a blockout.
2. Write a prompt naming the setting, lighting and scale. “A narrow street market, overcast morning, human-scale” beats “a city”.
3. Generate and wait — complex scenes take minutes.
4. Move the camera through the result and note where geometry breaks down.

Prompt to a place, not a feeling. The model understands “Viking longhouse” better than “an epic northern atmosphere”.

What can you actually do with the output?

A few real uses:

• Blockout for a level — generate a rough environment, then rebuild the layout in your engine.
• Background plates — walkable backdrops for a cutscene or a driving section.
• Concept art in 3D — far more useful than a flat image when a director wants to see around a corner.

Export options vary, but a mesh export you can import into Blender or a game engine is the practical path for most studios.

Is World Labs Marble free?

Access is limited and pricing is not a simple public number — this is an early product from a research lab, and availability has moved in waves. Expect either a waitlist or a paid tier tied to GPU-heavy generation. Check the site for the current state rather than assuming a free unlimited plan.

Where does Marble fall short?

Consistency over distance. A generated world looks convincing near the camera and looser as you move away from the starting viewpoint, because geometry outside the prompt’s focus is guessed. Interior detail also tends to be softer than exterior landmarks.

Texture resolution is another limit — good enough for backgrounds, rarely crisp enough for a hero asset in a close-up. Treat the mesh as a base and repaint details if the camera lingers.

Who is this for?

Level designers and environment artists who need a starting point, and indie teams that cannot afford a full art pass. If you need a final game-ready asset with clean topology and UVs, a generation model still will not give it to you.

Quick Summary

• World Labs Marble generates explorable 3D worlds from text, images or blockouts.
• Prompts naming a real place and lighting work better than emotional language.
• Best used for level blockouts, background plates and 3D concept art.
• Quality is strongest near the camera and weaker at a distance.
• Early-stage access and pricing — verify current availability before planning around it.

For object and asset generation rather than full environments, compare Tripo AI.