We can import models in a few types of file such as Wavefront (OBJ), as we explained in the Exporting section of Chapter 4, Preparing Visuals, which is a basic kind of file type that may or may not contain everything we need for the final deployment. Furthermore, OBJLoader class may not contain everything you'd want for a model loader either.
We want either FBX or OBJ, and we want to convert them to one of the two types that LibGDX handles best: G3DB and G3DJ.
For this, LibGDX provides a converter made by (Alias) Xoppa, called Fbx-Conv.
Go to https://libgdx.badlogicgames.com/tools.html and download Fbx-Conv from the Download hyperlink at the bottom of the app's box.
It will be a ZIP file, decompressed into a new and clean folder and easy to reach over the command line.
You can take a look at it in the following repository, https://github.com/libgdx/fbx-conv:
Windows - fbx-conv-win32.exe [options] <input>...
