Inter-Quake Model MIME Type

Understand Inter-Quake Model files, compatible tools, and Poly preview, search, and agent support.

MIME type details for `model/x-iqm`

In active use

MIME type	`model/x-iqm`
Extensions	`.iqm`
Magic number	`INTERQUAKEMODEL followed by a zero byte`
First standardized	2010; version 2 in 2011
Created by	Lee Salzman
Browser support	Requires a compatible 3D web viewer
Example applications	IQM developer-kit demo viewer, Compatible game engines
Poly support	Yes. Poly recognizes supported Inter-Quake Model files and provides 3D features when readable geometry is present.
Indexed by Poly	Yes. Search by filename and, after successful processing, visual similarity. Available geometry counts appear in 3D Details.
Preview in Poly	Partial. Interactive inspection of supported geometry; authored appearance and animation may differ.
Poly agent	Partial. 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 does `model/x-iqm` identify?

Poly uses model/x-iqm to identify Inter-Quake Model files with the .iqm extension. This is a Poly-recognized media-type label, not a claim of IANA registration. The format of the bytes still determines whether a file can be opened.

An .iqm file is an Inter-Quake Model, a binary format for game meshes and skeletal animation. It can store vertex attributes, triangles, joints, poses, and named animation ranges. The identifying header is INTERQUAKEMODEL followed by a zero byte.¹

File structure and background

The specification dates version 1 to April 2010 and version 2 to May 2011. Version 2 explicitly stores an additional quaternion component to reduce animation jitter.¹ IQM is distinct from its text-based interchange companion, IQE.

A signature helps identify a candidate file, but does not validate its contents. Header values and the rest of the data must agree. Changing a filename or media-type label does not convert an unrelated file into this format.

Opening and working with the file

The IQM developer kit includes a demonstration viewer and Blender exporter scripts. Those scripts export assets; they should not be mistaken for a built-in Blender importer.² To inspect an existing file, use the demo viewer or an engine that documents IQM loading.

When exporting a character, check that both the mesh and skeleton were included. The developer kit supports mesh and animation inputs separately, so the suffix alone cannot tell you whether a particular file has a visible model.²

Support in Poly

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.

A mesh-bearing IQM can receive visual features. Animation-only data does not by itself supply a complete model to inspect. Material names do not guarantee that companion images are present, and game-specific shading may differ.

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.

Conversion choices

For interchange outside an IQM-based game, export a copy as glTF. For a static mesh, OBJ is another option. Compare the character in several poses after conversion; a good rest pose alone does not verify bone weights or animation.

Lee Salzman. IQM format specification. ↩ ↩²
Lee Salzman. IQM developer kit. ↩ ↩²