Convert OBJ to MDD

Understanding OBJ and MDD file formats

OBJ is a widely used 3D geometry definition file format developed by Wavefront Technologies. It stores 3D model data such as vertices, texture coordinates, normals, and polygonal faces. OBJ files are popular for exchanging 3D models between different graphics applications.

MDD (Motion Designer's Data) is a file format used to store point cache animation data. It records the positions of vertices for each frame of an animation, allowing 3D models to be animated in various software packages by applying the cached motion data.

Why convert OBJ to MDD?

Converting an OBJ file to MDD is essential when you want to transfer static 3D geometry into an animation workflow that uses point cache data. This is common in visual effects, animation, and game development pipelines where motion data needs to be applied to a mesh.

How to convert OBJ to MDD

Direct conversion from OBJ to MDD is not typical, as OBJ files contain static geometry, while MDD files require animation data. However, you can use 3D software to import the OBJ, animate it, and then export the animation as an MDD file.

Best software for OBJ to MDD conversion

• Blender (Free and open-source):
  1. Import your OBJ file via File → Import → Wavefront (.obj).
  2. Animate your mesh as needed.
  3. Install the Point Cache Tools add-on if not already enabled.
  4. Export the animation as MDD using File → Export → MDD Point Cache (.mdd).
• Autodesk 3ds Max (Commercial):
  1. Import the OBJ file using File → Import.
  2. Animate the mesh or apply modifiers as needed.
  3. Use a plugin like PointCache to export the animation as an MDD file.

Tips for successful conversion

• Ensure your OBJ mesh is properly prepared and cleaned before importing.
• Remember that MDD files require animation; static OBJs will result in static MDD caches.
• Check compatibility of the exported MDD with your target application.

Summary

While OBJ files store static 3D geometry, MDD files are used for point cache animation. To convert OBJ to MDD, import the OBJ into a 3D application like Blender, animate it, and export the animation as an MDD file. Blender is a recommended free tool for this workflow.