[chimera-dev] Accessing rotation matrix of molecule models

Thomas Goddard goddard@cgl.ucsf.EDU
Thu, 18 Jul 2002 17:34:48 -0700 (PDT)


Hi Mike,

  I forgot to mention that the difference between the OpenState
localXform(xform) and globalXform(xform) routines.  These routines
change the current openState.xform by multiplying the xform argument
on the right or left respectively.  If c = atom.coord() and orig_xf is
the current openState.xform then the displayed position is orig_xf * c.
After calling openState.localXform(xform) the displayed position is

       orig_xf * xform * c,

while after openState.globalXform(xform) the displayed position is

      xform * orig_xf * c.

  Tom