
SAOimage blinking


blinking rapidly between different stored display images

The display, as it currently appears in the main display window,
can be stored by the workstation's display server by clicking on
the "blink" button in the scale submenu.  Three separate images
can be saved, each one associated with a different mouse button.
Each saved display is associated with the mouse button used to
click on the "blink" button, and replaces any previous image
associated with that mouse button.  The saved display image can
be redisplayed when in scale mode, by pressing its mouse button
while the mouse pointer is in the display window.

Because the blink image is saved at the display server end of the
X window system, it can be redisplayed much more quickly than the
normal image drawing used by SAOimage.  You will see the difference
when you release the blinking button.  To blink between saved
images, press down on another mouse button, before releasing the
earlier button.

The blinked image uses the existing color mapping.  The colors are
not restored to any previous setting.  Therefore, one should keep
the same color map settings when choosing displays for blinking,
or manipulate the color map to find a setting which works for all
of the blinking images.

Saved display images may all be of the current image, or, more
likely, may be made from different, successively loaded images.
The saved image can only be used for blinking.  Displaying a
saved image does not re-enable any other SAOimage functioning
for that image.  To be able to use the other functions on an
image which is not the most recently read image, the image must
must be reloaded from its file (or IRAF).

All saved displays must match the current display window dimensions.
SAOimage unsaves all saved displays when the display window is
resized.

Not all X servers are guaranteed to support display saving (called
pixmaps).  SAOimage will attempt to fall back on using image buffers
within SAOimage for saving image displays.  Unfortunately, some
uncooperative X servers have been known to crash, rather than
graciously decline the request.  You will quickly know if you have
such a server.  Problems may also occur when the user tries to mix
halftone and color pixmaps.
