Content Creators
Import custom items

Import custom items

You can import your own 3D models into the Builder. This allows you to pick models from a wide selection of free sources on the internet, or to create your own custom models.

Upload a model #

All custom items are stored in user-created asset packs. Each asset pack holds one or many assets.

To create a new asset pack:

  1. Open the editor for any scene and click New Asset Pack at the bottom of the item catalogue, or the plus sign at the top of the categories list.
  2. Drag a 3D model file into the window, or multiple files at once.
  3. Press Import assets.
  4. Name each asset, and potentially add tags to better identify them.
  5. Name the asset pack and press Create Asset Pack.

Now you’ll see a new folder in the items catalogue with your new asset pack, and you can use your new assets in any scene, just like the default items.

Once created, a custom asset pack is be available in every scene you edit as long as you log in with the same account.

Supported models #

All 3D models need to be in .glTF or .glb format. You can convert other formats into these formats with various different editors and tools. See 3D modeling for recommendations and tips.

All materials in the models need to be either basic material or PBR, and all textures need to be in sizes that are powers of two (ex: 256, 512). See Scene limitations for details.

If a 3D model relies on external files besides the .gltf file (like .bin or .png files) compress all the relevant files for the 3D model into a .zip file. Then import only this .zip file into the Builder.

All 3D model files must occupy less than 5mb to be imported into the Builder. Larger files aren’t supported.

Free libraries for 3D models #

Instead of building your own 3D models, you can also download them from several free or paid libraries.

To get you started, below is a list of libraries that have free or relatively inexpensive content:

📔 Note: Pay attention to the license restrictions that the content you download has.

Note that in several of these sites, you can choose what format to download the model in. Always choose .glTF format if available. If not available, you must convert them to .glTF before you can use them in a scene. For that, we recommend importing them into Blender and exporting them with one of the available .glTF export add-ons.

Colliders #

You might find that when running a preview the player can walk through your imported 3D models. This is likely because the models are missing a collider mesh to define a collision geometry. See colliders for more details and instructions.

💡 Tip: Instead of editing the model to add a collider mesh, a simpler alternative is to an Invisible wall smart item with approximately the same shape to stand in its place.

Animations #

If an imported model includes animations, the first animation that’s packed into the model will be played in a loop.

Note that you don’t have any control over when the animation starts or stops, or which one is played in case of several animations.

If there are multiple players in the scene, they may be seeing the animation out of sync from each other.

Smart items #

You can also import your own custom smart items that have built-in interactive behavior, following the same steps as for uploading a model. See smart items .