printim within an animation

[Sestak, Dr. Michael]

In the old days before printim (Grads v1.7b9 and before), double buffering
was necessary to speed up script driven animations.  When updating an old
script, I also just recently found that double buffering and printim are not
compatible.  So, to use printim (much faster than the old method, especially
when the time to run gxgif after the grads script is taken into account,
anyway), you must remove the set dbuff on and swap commands.

Michael Sestak
Fleet Numerical Meteorology and Oceanography Center
Monterey, CA

-----Original Message-----
From: Michael Boettinger [mailto:boettinger at DKRZ.DE]
Sent: Tuesday, September 13, 2005 12:49 AM
To: GRADSUSR at LIST.CINECA.IT
Subject: Re: printim within an animation


Hi Adam,

I encountered the same problem, but I found a workaround:
I was able to produce correct images (and without
error messages) when I switched double buffering off and
also added a 'clear' command after the 'printim' command in
the loop.

Good luck and best regards,
Michael

Adam Wolf schrieb:

> Friends -
>
> I am trying to animate a time sequence of a simulation.
> Every timestep, I write 4 images to a buffer screen,
> print the buffer using "printim", then swap the images.
>
> I get the following error every few frames:
> Logic Error 20 in gxhpng.  Notify Developer
>
> The program seems to be swapping the image before
> printim is finished writing the files.  The gif files that printim
> manages to create often are missing parts of the plot.
> (Note: if I print after swapping the gif is totally blank)
>
> I wonder if it is possible to introduce a delay between
> printim and swap that allows the gif to be created sucessfully.
>
> Does anyone have experience with this problem?
> I copied my script below
>
> Thanks - Adam
>
>              Adam Wolf
>
> Carnegie Institute of Washington
> Department of Global Ecology
> 260 Panama Street
> Stanford CA 94305
>                   *
>                       cel 510.207.8303
>                  adamwolf at stanford.edu
>             globalecology.stanford.edu
>
> ======================================
>
> 'open dailygrid2.ctl'
> 'set dbuff on'
> t = 10
> 'set lon -130 -50'
> 'set lat 15 55'
> 'set gxout shaded'
> while (t <= 365)
>   'set t 't
>   'q time'
>   result=subwrd(result,3)
>   hour=substr(result,1,2)
>   day=substr(result,4,2)
>   month=substr(result,6,3)
>   day=substr(result,4,2)
>   year=substr(result,9,4)
>
>   'set vpage 0   5.5 4 8.5'
>   'set clevs -5 -4 -3 -2 -1 0 1 2 3 4 5'
>   'draw title SIB  'day' 'month' 'year''
>   'd SIB'
>   'cbarn'
>
>   'set vpage 5.5 11 4 8.5'
>   'set clevs -5 -4 -3 -2 -1 0 1 2 3 4 5'
>   'draw title PCTM-Derived NEE'
>   'd NEE'
>   'cbarn'
>
>   'set vpage 0   5.5 0 4.5'
>   'set clevs -30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30'
>   'draw title dCO2 ppm'
>   'd CO2ABL-CO2FT'
>   'cbarn'
>
>   'set vpage 5.5 11 0 4.5'
>   'set clevs 0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1.0'
>   'draw title PBL turnover n/day'
>   'd W/PBL*86400'
>   'cbarn'
>
>    if(t < 100)
>    * This is where the error is occurring
>       'printim NEE0't'.gif gif x1100 y850 black'
>    else
>       'printim NEE't'.gif gif x1100 y850 black'
>    endif
>
>    'swap'
>
>   t = t + 1
> endwhile

--
_______________________________________________________
Michael Boettinger
Deutsches Klimarechenzentrum
Bundesstrasse 55
20146 Hamburg
Germany
email: boettinger at dkrz.de
phone: +49 40 411 73 344
fax: +49 40 411 73 270
http://www.dkrz.de/
_______________________________________________________