20040114: McIDAS 2003: mcimage issues using vncserver/vncviewer

>From: Michael Keables <address@hidden>
>Organization: DU
>Keywords: 200401141924.i0EJO8p2025290 McIDAS under VNC

Hi Mike,

I'm back from AMS...

>I'm trying to set up VNC sessions to allow my students to access McIDAS via
>our Windows computer lab (I did this two years ago without problems but am
>having issues this time around.) We have installed vncserver 3.3.7 on
>cyclone and created separate vnc sessions for each student to allow them to
>login to McIDAS and save their work to thier own directories on cyclone. I
>am having two problems:
>
>1. when I launch McIDAS in the Windows vncviewer, I get the following error
>message:
>
>mcimage: number of graphics colors plus image colors cannot be more than ...
>mcimage: Attempting to guess a good value

This shows that the XWindow emulation provided has a limited set of
colors available.  You can adjust how many image and graphics colors
McIDAS will run with on the command line/through the graphical startup
that pops up when you run:

mcidas -config

I recommend that you reduce the number of image colors to something
like 64 first.  I would try to keep the number of graphic levels at 16
if at all possible.  If the number of available colors is too small,
however, you may be forced to reduce below 16.  This would be bad since
products like the RTNEXRAD Level III images use an enhancement table
that has 16 entries and the NEXRCOMP Level III composites use an
enhancement that has 24 entries.

>When I then try to plot data:
>
>RAOBCON Z 500 USA CINT=60 COL=3
>Accessing Dataset Name = RTPTSRC/UPPERMAND.ALL
>PTCON:
>PTCON: first COL= argument is too big --> 3
>PTCON: Must be valid integer value within range 1 thru 1.
>PTCON:
>PTCON: Could not append COLOR to GRDDISP command
>PTCON:  Done
>RAOBCON: PTCON command failed
>RAOBCON - Done

So, McIDAS cut your number of graphics colors down to 1.  This is not
really a workable situation.

>Setting COL=1 yields:
>
>RAOBCON Z 500 USA CINT=60 COL=1
>Accessing Dataset Name = RTPTSRC/UPPERMAND.ALL
>Number of data points input to objective analysis:  99
>PTCON: Grid could not be contoured
>PTCON:  Done
>RAOBCON - Done

This problem should be entirely separate from the number of colors issue.

>When I launch the same command when logged in on cyclone, no problems (map
>plots, data are contoured, and I can use all color assignments without
>issue.)

This works since you have enough colors in your X session when running
on cyclone.

>All McIDAS batch files work fine when launched on cyclone, but I run
>into countless problems with the same routines when launched in a vncserver
>session. Images seem to display properly, although IMGDISP ALL= is limited
>to 4.

Are you saying that you can only put up loops of 4 images?  This is
very weird.

>2. GUI issues. Old GUI launches on startup for the student accounts

Just for clarification, what do you mean when you say "old GUI"?  My
v2003 distribution has two GUI interfaces, MCGUI and GUI, and an Fkey
interface which I strongly recommend not using.

>(not my
>existing account) on both vncserver instances and when logged in directly on
>cyclone (I even copied my .cshrc file to the student accounts and still have
>the same problem.)

I am confused about what the old GUI actually is.  If it is the Fkey
menu, then its running/not running is governed by settings in the
.mcidasrc file which should get created in each user's HOME directory.
The relevant lines in .mcidasrc look like:

Fkey:
-c 'MCMENU UNIDATA.MNU'

MCGUI:
-c MCGUI

SSEC GUI:
-c GUI

You just not have both MCGUI and GUI invocation lines in .mcidasrc
uncommented at the same time.  You can run the Fkey at the same time as
MCGUI and probably with GUI (I havn't tried this), but I don't
recommend it.

>Also, the student accounts can't find the observational data (image data
>loads, but they can't plot and display maps.)
>
>Suggestions?

Yes.  I suppose that the student(s) accounts is(are) not quite setup
correctly.

Something I wanted to get to in my previous email, but did not have
time since I was sitting in a booth in the exhibit hall.  I strongly
recommend that all non-'mcidas' accounts be configured to access data
through the remote ADDE interface that I recommend be setup on each
site's machine.  Using a setup like this, one does NOT have to run the
ADDE dataset stuff contained in LSSERVE.BAT.  Instead, the user
'mcidas' does all of the heavy lifting:

- setup ADDE datasets by copying DSSERVE.BAT to LSSERVE.BAT and making
  any modifications to match a user's setup and then run:

  BATCH LSSERVE.BAT

  from a McIDAS session

- setup the remote ADDE server (actually this is done by 'root')

- setup dataset location pointing by making a copy of DATALOC.BAT
  onto LOCDATA.BAT and then editing LOCDATA.BAT to set pointing
  of all datasets to the remote interface for all datasets that
  a user has.  In your case, you should be able to serve the following
  datasets off of cyclone:

  CIMSS
  NEXRCOMP
  RTIMAGES
  RTNEXRAD
  RTPTSRC
  RTWXTEXT
  TOPO

  The pointing is done after modifying LOCDATA.BAT (needs to be done;
  modification is not an option) and then running:

  BATCH LOCDATA.BAT

  from a McIDAS session.

Now, if the user accounts are setup according to the web documentation,
then each user will have defined in his/her session the environment
variables:

MCDATA
MCPATH
MCGUI
MCTABLE_READ
MCTABLE_WRITE

The last two environment variables control which dataset location files
to read from and which dataset location file to write to.  The idea is
that MCTABLE_READ for the non-'mcidas' user will be set to:

MCTABLE_READ="/home/user/mcidas/data/MCTABLE.TXT;/home/mcidas/data/ADDESITE.TXT"

and MCTABLE_WRITE will be set to:

MCTABLE_WRITE=/home/user/mcidas/data/MCTABLE.TXT

-- assumes that the user's HOME directory is /home/user --

Now, without the user doing anything, s/he will be pointed at the
external ADDE interface on the site machine for the datasets that are
hosted locally, and at external machines for datasets that are hosted
externally.  This is because ~mcidas/data/ADDESITE.TXT will be read and
settings in it used.  Hence, 'mcidas' has to do the leg work before
hand to make sure that this is setup (i.e., setup LOCDATA.BAT and run
'BATCH LOCDATA.BAT').

If the user wants to override the settings setup by 'mcidas', then s/he
can run DATALOC commands to point at different machines.  By virtue of
MCTABLE_READ being defined, his/her ~/mcidas/data/MCTABLE.TXT file will
be read and pointings will be used from there in preference to from
~mcidas/data/ADDESITE.TXT.

Do you want me to logon to cyclone as one user and set it up as I
recommend?  If yes, please give me the name of the user account and I
will have at it.

>Thanks in advance!!!

No worries.

>Cheers,

I will do the setup on cyclone as soon as you say you want me to, but I
first need a user name.

Cheers,

Tom

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