>>creating GIFs in batch -unmapped mode

[Emilio Mayorga <emiliom@xxxxxxxxxxxxxxxx>]

Hello,

Thanks to Steve Hankin, Kevin O'Brien, Mark Verschell for helping with
this problem. The problem and solution are below:

Emilio Mayorga

====================================================================

	>I have tried using Ferret in batch mode with the -unmapped 		>option
to produce some graphics, but I've gotten strange 		>results. We have
SPARC 2 & 10 workstations running Solaris 2.4, 	>with Ferret 4.45. When
I run this batch script with -unmapped 
	>to produce a gif file, I get a blank, white image (which, 
	>however, has been resized to the window aspect I requested!).
 
	>However, when I did the same thing but while running from my X 
>emulator from my PC, I didn't get a blank page, I got the 		>graphics with a background filled with "noise" (like TV static) 	>or fragments of my graphics. It looks like whatever actual 		>drawing I request (shade, text, labels, legends, etc) does get 	>drawn in this case, but everything else is scrambled.

 On Mon, 19 May 1997, Steve Hankin wrote:

Hi Emilio,
 
Kevin O'Brien points out that if you give a command that forces a redraw
of the window, such as SET WINDOW/SIZE or drawing into a previously
drawn viewport, and then request the GIF image immediately (with FRAME)
you can get a garbled image.
-------------------------------

In fact, this is what I was doing in my batch script. By avoiding a
forced redraw of a window (such as by putting all SET WINDOW/SIZE=## and
SET WINDOW/ASPECT=## commands together at the beginning, before any
plotting command is issued), the GIF was created without any problems.

Mark has had similar problems with SGIs, and he's found that he can
create PostScript graphics from ferret, then convert to GIFs by using
pstogif utilities. 

Emilio Mayorga
________________________________________________________________
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