The General Device Type Format is a file format that is used to describe fixtures of the entertainment industry. This allows to define the geometry and how it reacts to DMX input.
A GDTF file consists of an XML file that contains the description and several resource files such as geometry data and gobo images. The format for 3D data is 3DS and for images PNG. These files are bundled in a ZIP archive without compression.
The current version of GDTF is: 0.88
The My Virtual Rig format is a file format that is used to share data for a scene between a lighting console, a visualizer, a CAD program or similar tools. This allows to transfer parametric and geometric data between different programs.
An MVR file consists of an XML file that contains the description of the scene and several resource files such as geometry data, textures and GDTF files. The format for 3D data is 3DS and for textures PNG. These files are bundled in a ZIP archive without compression ending in ".mvr". All files stored in the archive have to have a SHA-256 checksum file next to the original file. The ending of the checksum file is ".checksum.txt".
The current version of MVR is: 1.3
Conveniently Vectorworks provides a portable C++ library that can read and write MVR files.
Here you will find a description of the file format and tutorials that will help you to create GDTF and MVR files.