AC3D model MIME Type

Learn what model/x-ac identifies, how AC3D model files are encoded, and how Poly supports them.

MIME type details for model/x-ac

In active use
MIME typemodel/x-ac
Extensions
.ac.ac3d.acc
First standardizedUnknown
Created byInivis Limited
Browser support
Example applicationsAC3D, Blender
Poly supportPartial. Poly recognizes this 3D media type and processes supported files.
Indexed by PolyYes. Poly indexes filenames and visual similarity for processed geometry; scene counts are displayed in Details.
Preview in PolyPartial. Poly provides an interactive preview for supported constructs.
Poly agentYes. An optimized rendition of the 3D object or scene is provided to the agent, allowing compact yet information-rich multimodal interaction with 3D files.

What does model/x-ac mean?

AC3D is a compact text format organized as a header, a material palette, and objects. The format guide documents headers such as AC3Db, quoted names, surface definitions, and optional sections. It is designed to be simple to parse, but the version marker matters: newer files may use constructs an older reader does not know.1

Inivis describes the .ac format as widely supported and recommends choosing an older export version when sharing with software that has not updated its loader.2 The .ac3d and .acc suffixes are recognized aliases in Poly's filename mapping; the content still needs to be AC3D data.

The associated extensions are .ac, .ac3d, .acc. The media type identifies this format family; it does not convert bytes or guarantee that a reader supports every feature.

Poly support

Poly can recognize this type as 3D content, index filenames and visual similarity for processed geometry; scene counts are displayed in the Details panel, and provide an interactive preview when the file imports successfully. An optimized rendition of the 3D object or scene is provided to the agent, allowing compact yet information-rich multimodal interaction with 3D files.

ConstructWhat to expect
Geometry and scene structureAvailable when import succeeds.
Materials and texturesDepends on source constructs and supported rendition features.
Cameras, lights, and animationAvailable when present and supported.

Opening and conversion

Use AC3D or another format-aware tool when preserving editability matters. glTF or OBJ can be practical interchange targets for geometry, but conversion may discard format-specific scene data.

Footnotes

  1. https://sites.google.com/view/ac3dfileformat/home.
  2. https://inivis.com/ac3d8.html.
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