20000505: SFCMG erases panels before plotting

>From: Bill Fingerhut <address@hidden>
>Organization: Lyndon State
>Keywords: 200005051846.e45IkvG17682 McIDAS-X 7.6x SFCMG PANEL

Bill,

>We have discovered some odd behavior with McIDAS' SFCMG
>command. If one creates 4 panels on a frame with PANEL 2 2;
>then proceeds to place meteorograms in each panel, (using 
>same station to eliminate variables),
>SFCMG KBTV PAN=1
>SFCMG KBTV PAN=2
>SFCMG KBTV PAN=3
>SFCMG KBTV PAN=4
>panel 1 is erased just before panel 2 is drawn. Drawing in
>panels in a different order produces similar results, i.e.
>occaisional erasure of one panel.

I verified your observation and understand what is going on.

SFCMG has an EG= keyword whose default value is YES.  The code in
sfcmg.c that generates an erase command is assuming that the PAN=
keyword sequence (a global keyword in McIDAS-X since Version 7.0 or
7.2) will be picked up by EG.  The panel that will be erased is being
determined by the position of the cursor in the frame (or the last
position in the frame if it is no longer in the frame).

I will take a look at the code to figure out why the the PAN=
specification is not being picked up by the EG invocation.  Again,
I think it should be since it is a global keyword.

In the mean time, you can get around the problem by specifying
the EG=NO sequence on your SFCMG command lines:

EG PAN=1 4
SFCMG KBTV PAN=1 EG=NO
SFCMG KBTV PAN=2 EG=NO
SFCMG KBTV PAN=3 EG=NO
SFCMG KBTV PAN=4 EG=NO

Tom