Return to Castle Wolfenstein Model .mdc
A compressed MD3. Same idea, much smaller frames.
What an .mdc file holds
MDC is Return to Castle Wolfenstein’s model format, built as a space-saving variant of Quake III’s MD3. Most animation frames are stored as small offsets from a base frame rather than as full vertex positions, which cut model sizes substantially at a time when that mattered a great deal.
Commonly seen in: Return to Castle Wolfenstein, Wolfenstein: Enemy Territory, idTech 3 forks.
| Data | Stored in MDC |
|---|---|
| Geometry | Yes |
| Materials and colour | Yes |
| Texture maps | Yes |
| Animation and rigs | Yes |
| Scene hierarchy | No |
| Read here | Yes |
| Written here | No |
Tested against a real file
The last sweep loaded spider.mdc from Assimp test models through the viewer on this site: 1,368 triangles across 19 meshes and 19 materials, in 2.2 seconds. Every format's result is on the test results page, run 2026-09-08.
Convert MDC to another format
Every pairing has a page saying what survives the trip.
Other things to do with an .mdc file
Questions about MDC
How do I open an .mdc file?
Drop it into the viewer on this site and it opens in the browser, with the scene tree, the materials and the mesh statistics. Nothing is uploaded. If you want it in another program instead, convert it to GLB, which almost everything reads.
Is MDC a good format to archive in?
MDC carries geometry, materials, textures and animation, so an archive copy keeps nearly everything. The usual caveat applies: a format is only as future-proof as the readers that exist for it, and .mdc is well served.
Does converting MDC lose quality?
Geometry is copied vertex for vertex, so the shape does not degrade. What gets lost is whatever the target format has no field for: convert to STL and the materials go, convert to OBJ and the animation goes. The comparison table on each converter page says exactly which.
Formats that hold the same things
Or go back to the full format reference.