These are all more-or-less standard graphics models, though some have
been resized to use fewer triangles than their full-resolution counterparts,
and all have been converted into .hem format, a custom format based loosely
on the ASCII .obj format.  A comment header at the beginning of each file
gives a quick overview, or you can read the code inside the Utils/ModelIO/ 
directory.  

The reason for this format is that we use an edge list for silhouette 
extraction (and some of my research, though not this project, uses 
triangle-adjacency information).  This data is not easily determined
using most off-the-shelf .obj readers I have access to (e.g., Nate Robin's
OBJ parser).  Instead of coming up with some efficient way to calculate
the information I need, I simply precomputed it and store it inside this
modified file format.

-Chris