3DS

Overview
This is the original (legacy) file format for Kinetix' 3D Studio and 3D Studio MAX product line (now part of AutoDesk). It contains the 3D model data for the complete scene.

Resources

 * Wikipedia page on 3DS
 * reverse-engineered specs
 * more reverse-engineered specs
 * Specification from FileFormat.info here
 * LGPL library for reading/writing 3DS files here