#### display single or average curvature ####
-------------------------------------------
funct (left-click): read single subj curv
  set curv <infile>
  read_binary_curv
-------------------------------------------
alt funct (if *.tif): read morph target frame
  set template <some_template.tif>
  read_tif_template <frame>
-------------------------------------------

The "R" button on the "curv:" entry line reads
curvature from file whose name is current value
of $curv (entry at left).  In a tcl script, to
read the standard subject dir curvature file,
use:

  setfile curv ~/surf/$hemi.curv  ;# globs
  read_binary_curv

By contrast, to read in an arbitrary file as
curv, use:

  set curv /some/random/curvature/file
  read_binary_curv

If the selected file ends in *.tif, the file will
be assumed to be a multi-frame, 256x512, 32-bit
per pixel MGH template (tcl filename variable:
$template).  A pop-up will appear to allow
selecting one of the frames to load.  In a tcl
script, this could be done with:

  set template /Applications/freesurfer/average/$hemi.average.curvature.filled.buckner40.tif
  set templateframe 6
  read_tif_template
