.x3db File Extension

Learn what .x3db files contain, which applications open them, and how Poly supports them.

File extension details for .x3db

Partial Support
File typeExtensible 3D compressed binary encoding
MIME type
EncodingCompressed binary X3D, commonly Fast Infoset based
Operating systemsWindows, macOS, Linux
Opens withXj3D, InstantReality, FreeWRL
Poly supportStorage Only. Poly recognizes binary X3D filenames but does not currently import them for 3D previews.
Indexed by PolyYes. Poly indexes the filename and basic file metadata.
Preview in PolyNo. Poly does not currently import binary X3D for 3D previews.
Poly agentNo. Poly does not currently provide binary X3D scene content to the agent.

What kind of file is .x3db?

X3DB is X3D's compressed binary encoding. Web3D describes conversion from a canonical X3D representation into a compressed binary stream and defines .x3db with model/x3d+binary.1 It is a separate representation from XML X3D, so renaming the suffix does not convert the file.

How do I open a .x3db file?

Xj3D and InstantReality can open or import many Extensible 3D compressed binary encoding files. Check export settings when a model contains materials, textures, lights, cameras, or animation. Conversion can discard format-specific data.

Poly support for .x3db

Poly recognizes .x3db as a stored binary X3D file and indexes its filename and basic file metadata. It does not currently import binary X3D for a 3D preview or agent interaction.

ConstructPoly behavior
Geometry and scene structureAvailable when the file imports successfully.
Materials and texturesDepends on the constructs present and supported rendition.
Lighting, cameras, and animationAvailable when present and supported.

Working with .x3db

Keep the source before converting. glTF is a practical real-time delivery target. For CAD or BIM, retain the original exchange file and record its schema or application protocol.

Footnotes

  1. https://www.web3d.org/documents/specifications/19776-3/V3.3/Part03/concepts.html.
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