In this tutorial Isaac Oster details the HDA UI, node network, and python scripting behind an atlas texture generator, created with Houdini.  This tutorial demonstrates a number of features in Houdini, including dynamic UI elements, procedural node creation, creating custom functionality with Python, and baking and exporting textures and geometry.

Atlas textures are created by combining assets with unique UVs and textures, re-laying out the UV shells, and baking the original input texture maps to the new UV layout.  Atlasing offers a number of performance optimizations and is an important component of efficient game art.

Special thanks to @Michael Pavlovich , @Indie-Pixel , and @Ben House  for their excellent Houdini tutorials.