-------------------------------------------
funct (left-click w/label="area"):
  set area <infile>
  read_binary_areas
-------------------------------------------
funct (left-click w/label="area2"):
  set area <infile>
  read_binary_areas2
-------------------------------------------


Detailed Description of Area "R" Button Actions

-------------------------------------------
function (left-click w/label="area"):
  set area <infile>
  read_binary_areas
-------------------------------------------

The "R" button on the "area:" entry line reads
the local area from file whose name is current
value of $area (entry at left).

Reading an area file defines the "original area"
of each vertex (the .origarea field).  An
original area file is typically generated at
surface-making time from the $hemi.white surface.
On startup, tksurfer loads this file ($hemi.area)
regardless of which surface is being displayed
(other original area files include:
$hemi.area.mid and $hemi.area.pial).

The "original area" values (in the .origarea
field) as well the the current surface area
values (in the .area field) are both reported
when doing a FILL to create a patch or label.

Note that unlike other entries, the "R" and "W"
buttons (which use functions read_binary_areas
and write_binary_areas) read to and write from
*different* data fields:

  read_binary_areas:    areafile -> .origarea field
  write_binary_areas:   .area field -> areafile

That is, "R" (read_binary_areas) reads an area
file as an "original area" (into the .origarea
field), while "W" (write_binary_areas) writes out
the "current surface local area" (the .area
field) to an areafile.

If you try to overwrite the original area file
($hemi.area) with the current area using the "W"
button without changing the output file name,
there will be a warning.

-------------------------------------------
Alt funct (left-click w/label="area2"):
  set area <infile>
  read_binary_areas2
-------------------------------------------

If the "area:" label is left-clicked so that it
changes to "area2", an alternate function,
read_binary_areas2, is used to read the selected
area file into the .origarea2 field.

This is used for calculating area ratios (see
R-click help for "area:" label).
