[mapserver-users] Sliver when displaying 0°-360° NetCDF data in EPSG:3857

[Jeff McKenna]

Hi Louis-Philippe,

With much kind respect, the test case that you provided was not very 
simple, so I had to spend much effort to create a tiny test case, that 
contains one of your NetCDF files, and a small mapfile that simply 
reprojects the file into EPSG:3857 (without WMS etc.).  The small test 
case contains a single shp2img command to replicate the issue (in a file 
'commands.txt') which you can download at 
https://gatewaygeomatics.com/dl/netcdf-2020-06-26.zip

The issue that you report, of a sliver (no data) in the map when 
reprojecting to 3857, is visible in the resulting map images in the live 
demo at: 
https://demo.gatewaygeomatics.com/cgi-bin/mapserv?MAP=/home/apps/netcdf/2020-06-26/netcdf-test.map&MODE=browse&TEMPLATE=openlayers&LAYERS=all 
  (this server is running MapServer-master)

This should be filed as a new ticket at 
https://github.com/mapserver/mapserver/issues and point to this test 
zipfile.

Have a nice weekend,

-jeff




-- 
Jeff McKenna
MapServer Consulting and Training Services
co-founder of FOSS4G
http://gatewaygeo.com/



On 2020-06-26 10:00 a.m., Rousseau Lambert2, Louis-Philippe (EC) wrote:
> Hi,
> 
> This issue is related to:
> 
>   * https://github.com/mapserver/mapserver/commit/722716c49de2399f54b275ab31437f0e8c92cd63
> 
>   * https://github.com/mapserver/mapserver/commit/4c2aeb4bbd229723d8ea67c337cf02350575b2ae
> 
> 
> The issue is that when I try to visualize (via WMS) a layer with a 
> NetCDF data file with longitude from 0° to 360° in EPSG:3857, there is a 
> sliver around longitude 0° where no data is displayed.
> 
>