Change here object and crystallographic data for a single plane or a list of planes.
To modify a plane, click over its graphic image, or write its identification
(name and number) on the 
Plane entry. To modify a list of planes, press
the button 
List (after creating the list of planes with 
Plane->Select).
Parameters for empty entries or 
Local choices remain unchanged.
To change a plane name write the new name in the 
Plane entry,
followed by the plane number (GAMGI needs the number to identify the plane).
To change the name for a list of planes, press 
List first
and then write the new common name in the 
Name entry.
Reference
GAMGI can handle crystallographic planes (selecting 
Cell), related with
a cell containing the relevant crystallographic information, and atomic planes
(selecting 
Atoms), defined by three non-colinear atoms.
For a single plane, 
Reference can be 
Cell, 
Atoms
or 
Local. For a list of planes, 
Reference must be 
Local.
When 
Cell or 
Atoms is selected, the plane is recreated
from scratch (as if using 
Plane->Create) and its old content is
removed. As this requires local information for each plane, it cannot
be done for a lists of planes. When 
Local is selected, previous
features and contents are preserved, unless when specifically changed.
Cell
To create crystallographic planes, set 
Reference to 
Cell.
GAMGI automatically shows a 
Cell entry, 
h, 
k, 
l     
entries to indicate the plane indices, plus a 
Vectors menu, to select 
the cell vectors to use, 
Conventional or 
Primitive. For the sake 
of simplicity, GAMGI does not accept 4-indice notation for planes or directions 
in hexagonal cells.
Pressing the mouse over a cell in the current layer, the cell identification
is automatically written in the 
Cell entry. When a valid cell is found
and its 
Type is 
Projection, the default 
Polygon page                 
is automatically replaced by a 
Projection page.
Atoms
When 
Reference is set to 
Atoms, GAMGI automatically shows
three 
Atom entries. Pressing the mouse sucessively over three 
non-colinear atoms in the current layer, the three entries become occupied
and the plane defined. After pressing 
Ok, an error is shown if the 
atoms are disposed linearly.