Export an Armature w/Mesh for each Frame

Hello, I’m trying to export an animated mesh to DirectX…in order to calculate the bounding box for a certain frame, the frame must have a list of vertices. Can I assign certain vertices to their corresponding frames so that the exported file contains a Mesh{} tag for each Frame{}…?

DirectX file format has a format like so:

Armature {
Frame {
Mesh {
} // End Mesh
} // End Frame
} // End Armature

I would like to export a file that has a separate frame & mesh for each part of the body. I would like to calculate a bounding box for each part of the body.

As things are now, I have one giant Mesh {} tag for all vertices within the armature.