In the older UCSF MidasPlus incarnation of your software, there was a feature that allowed an interface with Gregort & Cohen's QPACK software for coloring according to molecular packing density using a sphere growth method. Per residue packing scores were applied with a color range after running qpack with the special option, '-m'. http://www.cmpharm.ucsf.edu/cohen/software/pages/qpack.html In the primary literature report of QPACK, it was suggested by the authors that they would work to make this feature available in UCSF MidasPlus and 'its successors'. Since this is a very fast and convenient way to evaluate the quality of models, I would like to recommend/request that this feature be enabled (or added) to Chimera. In MidasPlus, it was a command line option. The user simply entered qpack; there was a .midasrc file that contained the explicit local path to the qpack binary as well as a command line script to launch the package with the '-m' option. Thanks for your consideration of this suggestion. Best regards, Eric ______________________________________________________________________ Eric S. Dawson, Ph.D. CSB Computation, Education & Outreach Research Instructor, Biochemistry Center for Structural Biology (CSB) 5137 MRBIII Vanderbilt University Nashville, TN 37232-8755 Tel: (615)-936-5579 (MRB III) Tel: (615)-322-3303 (5119 SC) Fax: (615)-936-2211 "All that is gold does not glitter, not all those who wander are lost." J.R.R. Tolkien - Fellowship of the Ring