The Disney Ptex library has been released as open source under the BSD license
The Disney Ptex library is now available to the public community of texture artists, lighters and modelers.
rest here
http://features.cgsociety.org/story.php?story_id=5439
also
Disney Ptex
http://ptex.us/overview.html
Source Code
http://github.com/wdas/ptex/
Google discussion group
http://groups.google.com/group/ptex