Hi Oliver, Chimera does have a “center of view” option for center of rotation, check it out! The default is “front center,” however, since the actual midpoint between the front and back clipping planes is often farther back in Z than you might expect. You can change center of rotation method via Rotation tool (it’s one of the tabs in the same dialog as the Side View) or with the command “cofr”: <http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/sideview.html#rotation> <http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/cofr.html> I hope this helps, Elaine ---------- Elaine C. Meng, Ph.D. UCSF Computer Graphics Lab (Chimera team) and Babbitt Lab Department of Pharmaceutical Chemistry University of California, San Francisco

On Jun 20, 2015, at 12:45 PM, Oliver Clarke <olibclarke@gmail.com> wrote:

Hi, I have a request for a future version of Chimera - would it be possible to add a command or menu item that (reversibly) locks the center of rotation to the center of view, such that when the view is translated, the cofr is updated automatically also?

This is the way structure navigation works in Coot, and I find it is a much more intuitive and precise way to travel when examining the finer details of a structure (as one would expect given that the main purpose of Coot is model building while Chimera is exceptionally good for structural analysis and visualization).

This would make navigation of large structures much easier, particularly when one is just browsing around the structure. In addition, it would be nice to have a dynamically updated pseudoatom to indicate the current center of rotation - this is implemented in Coot as the “pink pointer”, and I find it very helpful for getting my bearings.

Cheers, Oliver.