SAOimage keyboard input

Many of the keys on the keyboard are mapped to perform useful functions.
Striking the key results in an immediate response.  The response may be
dependent on the window in which the mouse cursor is positioned.  Some
responses are also dependent on the main menu mode (i.e. Cursor).  Both
upper and lower case are mapped the same.

In addition to the instant action keys, the control, shift, and meta (left
and right) keys change the response to mouse actions when held down while
performing the mouse action.

Sometimes, SAOimage will ask for text or numeric input with a pop-up
window.  Input in this situation is as one would expect and is
unaffected by the mappings which are otherwise in effect.  The cursor
read-back mode of IRAF, also overrides many keyboard functions.


Mapped key commands

 Up Arrow, Down Arrow, Left Arrow, Right Arror:
	The four arrow keys can be used to move the mouse cursor one
	screen pixel in the given direction.  The mouse interaction is
	exactly as if you moved the mouse by hand.  This facilitates
	fine positioning and works in all windows and all modes.

 R:	("raise") Raise all SAOimage windows to the front of any other
	windows on the screen.  The 'A' key also performs this function.

 A:	("refresh") Raise and redraw the display windows.  This is 
	equivalent to ctrl-L in a character terminal window.

 N:	("new") enter new command-line arguments.  This brings up a popup
	window for text input.  Use the same switches and arguments as you
	would on the command line (see cmdline help).  All of the command
	line arguments which affect selection and display of an image can
	be used.  Some configuration arguments (e.g. -d, -g, & -G) are not
	affective at this time.

 T:	("table") When the mouse is in the main display window or the pan
	window, this prints a table of the pixel values surrounding the
	current mouse position.  The table is printed in the terminal
	window from which SAOimage was called.  The values are scaled to
	their original file values.  (L has a seemingly similar affect
	but is useful only for debugging purposes).

 S:	("save") When in cursor mode, and the mouse is in the display
	window, the current cursor is saved as a region (of type include).

 E:	("exclude") When in cursor mode, and the mouse is in the display
	window, the current cursor is saved as a region (of type exclude).

 D:	("delete") When in cursor mode, and the mouse is in the display
	window, the smallest region which encloses the mouse is deleted.
	In the case of a point region, its area is defined as the area of
	the first character of its label.

 Delete:
	When in cursor mode, and the mouse is in the display window, the
	most recently saved region is deleted.



Modifier keys

    For an explanation of mouse clicking and dragging, see the help
    section on mouse control.

 Shift:
	Holding the shift key down toggles the 'track' and 'coord'
	tracking actions.
	      If no tracking was selected and the mouse is in either the
	  main main display window or the pan window, touching the shift
	  key will update the magnifier window to the current mouse
	  location.  If the mouse is in the main display window, the
	  coordinates and pixel value will also appear in the upper
	  right, above the buttons.
	      If you are in Color mode and dragging the mouse with a
	  button down in either the main or color graph window, the
	  graph will be updated to the current state of the color table.
	      By contining to hold the shift key down, tracking will
	  continue to update as you move the mouse.
	      If you were tracking before touching the shift key,
	  pressing the shift key will suspend tracking, enabling you to
	  preserve the existing tracking displays while moving the mouse.

 Caps or ShiftLock:
	Toggling to caps mode by using the Caps or shift lock key has
	the same effect as holding the shift key down.  When using this
	option, you may need to toggle it off to make normal text entry
	in the pop-up or a terminal window.

 Control:
	When manipulating the color map in the main diplay window,
	holding the control key down, restricts the affect to only the
	color(s) corresponding to the mouse button(s) being pressed
	(left=red, middle=green, right=blue).

 Meta keys:
	The meta keys have traditionally been used for window manager
	functioning.  SAOimage normally ignores keyboard and mouse
	input while a meta key is held down.


Pop-up text and numeric input:

    When SAOimage needs string input such as the name of a file or new
    command line arguments, it presents a pop-up window for you to
    type in.  The line starts with a default already typed in.  Many
    keyboard editor keys are recognized, including the arrows.  The
    popup window also recognizes many EMACS style line edit commands.
    The input is taken when the user strikes the return key.

 CtrlA:  Move text cursor to beginning of line
 CtrlB:  Move the text cursor back one character (backspace)
 CtrlC:  Abort the interaction and return to SAOimage
 CtrlD:  Delete the character under the text cursor
 CtrlE:  Move the text cursor to the end of the line
 CtrlF:  Move forward one space
 CtrlG:  clear escape if just typed
 CtrlK:  Delete all characters from the text cursor to the end of the line
 CtrlN:  recall next input line (clear input line if no next in buffer)
 CtrlP:  recall prior input line
 Delete: Delete character before the text cursor
 escape B: move to beginning of previous word
 escape D: delete to end of next word
 escape F: move to end of next word

    For numeric input, the typed input must be in acceptable integer or
    real (where allowed) format.  Multiple entries, when desired, must be
    separated by spaces, commas, or tabs.  (The line is read using scanf).