[ferret_users] graticules are not written in overlay-plots

[Martin Schmidt <martin.schmidt@xxxxxxxxxxxxxxxxx>]

Hello Ferreters,

sometimes it is nice to overlay a shaded image with a filled image. 
Graticules are useful too.
Ferret offers this, but it needs tricks to get it working:

For example:
ferret
        NOAA/PMEL TMAP
        PyFERRET v7 (opt)
        Linux 3.19.0-64-generic - 07/01/16
        27-Jan-17 10:17

yes? use coads_climatology
yes? set region/x=0:100/y=-50:0
yes? shade/l=1/grat sst
fine

yes? fill/over/l=1/grat sst

not fine - graticules are lost in ocean areas. Is this eventually a bug?

I see the point, that two separate plots produced with "shade" and 
"fill" cover different regions (half a grid cell width?) and have 
different axes.
So I understand, that "grat" becomes silent, when "overlay" is 
specified. But I think it would be reasonable to redraw the graticule 
from the first plot that defines regions and axes, when another plot is 
overlayed?

There are several workarounds, i.e., using fill_xy, but as a wish, it 
would be great to keep the graticules in overlayed plots, if "grat" is 
specified.

Best,
Martin