What OpenCTM is (and what it's not)

OpenCTM is primarily a file format for storing 3D triangle meshes in a compact yet versatile format. In order to make it easy for software developers and 3D designers to support the format, an easy to use software library is provided that can read and write OpenCTM format files.

It is important to understand that OpenCTM is only concerned with managing triangle mesh data. In other words, OpenCTM is not a scene description format. For instance, OpenCTM does not handle multiple meshes, transformation matrices, materials, light sources, physical properties, etc.

While most 3D file formats with scene description capabilites tend to be quite application or technology specific, OpenCTM is suitable for almost any application. Any online e-shopping system, game engine, medical application or phone widget is free to tailor a scene or model description format of their own, and use OpenCTM as the 3D data carrier format. A typical scene file format could be a ZIP archive containing an XML file for the application specific scene and material descriptions, along with several OpenCTM files for the geometry data and JPEG files for the textures.


File format

Bunny in the ctmviewer

The file format has the following features:

Software library

The software library has the following features:

OSI certified [tm]


The included 3D file converter (ctmconv) has the following features:


The included 3D file viewer (ctmviewer) has the following features:


The following documentation is available: