Problem with Graticule and polar stereographic projection

[Sean Gillies]

On May 18, 2005, at 5:44 PM, Steve Roberts wrote:

> Hello,
>
> I am having problems with using a graticule on a polar stereographic
> projection. When the map is centered near the north pole all the
> lat/lon
> lines disappear from the center of the image. You can find an example
> at:
>
> http://www.joss.ucar.edu/cgi-bin/catalog/mapserv?
> mode=map&layer=GRID&map=/web/catalog/bug/grid_test.map
>
>
> I'm also seeing spurious straight line segments that parallel the
> latitude
> lines. This site is using mapserver-4.2.3 on SunOS 5.9 sparc
> SUNW,Ultra-6.
> However I see the same problem with mapserver-4.4.2 on linux Mandrake
> 10.1.
> Any help in solving this problem would be greatly appreciated. Below
> is the
> sample grid_test.map file.
>
> Thanks,
> Steve
>

Steve,

I'm having more success with my own graticule shapefile than with
MapServer's built-in grid, and I also take care to not extend my
meridians all the way to the pole.  Here's a polar stereographic
example:

     http://zcologia.com/files/stars_stere.png

cheers,
Sean

--
Sean Gillies
sgillies at frii dot com
http://zcologia.com