.b3d File Extension

Understand Blitz3D model files, compatible tools, and Poly preview, search, and agent support.

File extension details for .b3d

Partial Support
File typeBlitz3D model
MIME type
EncodingLittle-endian binary chunks
Operating systemsWindows, macOS, Linux
Opens withBlitz3D, Luanti
Poly supportYes. Poly recognizes supported Blitz3D model files and provides 3D features when readable geometry is present.
Indexed by PolyYes. Search by filename and, after successful processing, visual similarity. Available geometry counts appear in 3D Details.
Preview in PolyPartial. Interactive inspection of supported geometry; authored appearance and animation may differ.
Poly agentPartial. An optimized rendition of the 3D object or scene is provided to the agent, allowing compact yet information-rich multimodal interaction with 3D files. This requires an available visual rendition.

What kind of file is a .b3d?

A .b3d file stores a Blitz3D model. Its binary chunks describe meshes, material brushes, texture references, bones, and animation keys. The format begins with a BB3D root chunk and can nest model nodes inside one another.1

Poly uses the model/x-b3d identifier for this format.

How do I open a .b3d?

Use Blitz3D for an original Blitz project. Luanti also supports B3D models, particularly for animated game entities; it is a game engine rather than a general modelling editor.2 For editing, keep the source project and use an exporter or importer that explicitly supports B3D. Installing Blender alone does not establish B3D import support.

A material can name a separate texture, so a model file is not necessarily the whole asset. Keep the original model and its companion images together. An untextured preview can still show useful geometry, but it is not evidence that the original character had no textures.

Poly support for .b3d

Poly lets you orbit, pan, and zoom around supported geometry. Find the file by name, or use visual similarity once its visual content is available. The details panel shows available mesh, material, vertex, triangle, and other scene counts.

Game-specific material effects and external textures may differ from the original game. Available animation clips can be played when supported, but verify deformation in the target game before shipping an asset.

An optimized rendition of the 3D object or scene is provided to the agent, allowing compact yet information-rich multimodal interaction with 3D files. You can ask about the object's visible shape or compare assets, while retaining the original for authoring work.

History and alternatives

B3D grew out of the Blitz3D programming environment, where game-ready animated objects needed more than a bare triangle list. The published specification remains useful for understanding older assets.1

Choose glTF for modern scene exchange or OBJ for a static surface mesh. Before accepting a conversion, compare the silhouette and pose with the original game asset. A static export cannot preserve a character's motion.

Footnotes

  1. Luanti documentation. Original Blitz3D file-format specification. 2
  2. Luanti documentation. Supported model formats.
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