Csurf current 3d volume select (next to bottom line)

The set of radio buttons to the right of the
VOLUME button picks the 3D volume dataset to load
when VOLUME is clicked.  The standard volumes, in
the order in which they are generated, are:

  orig -- original (can be avg of several)
  T1 -- normalized (wm -> std value)
  PD -- proton density (optional)
  PDbrain -- skull-stripped PD (optional)
  brain -- skull-stripped T1
  wm -- wm-only segmentation
  filled -- binary fill of wm (surf made from this)

The *.mgz suffix is omitted.  For example, if
"orig" is clicked, these files are looked for
in this order:

  1) $subject/mri/orig/COR-001, etc
  2) $subject/mri/orig.mgz

A volume (CORdir or .mgz file) in $subject/mri
with a non-standard name can be loaded by
selecting it from the dropdown to the right (or
typing its name into the entry).
