AW: [UMN_MAPSERVER-USERS] Map Projections

[Ryan Ollerenshaw]

Hello Arnd,

Thank for for the  reply.  The main problem that i am having is i have some
datasets with a prime meridian at 0 degress and others that have a prime
meridian at 90 degrees and i need these raster datasets to line up. but when i
specify a map projection as:

PROJECTION
  "proj=cc"
  "lon_0=90w"
  "ellps=WGS84"
  "datum=WGS84"
END

and a layer projection as:

PROJECTION
  "proj=cc"
  "lon_0=0"
  "ellps=WGS84"
  "datum=WGS84"
END

Rather then the layer geting reprojected to the map projection I get a blank
image.  I do however get a different map image of i just change the projection
name of the map file to some like: lcc or merc.  But why am i getting a blank
image when i try to shift the prime meridian?

Thank you for any help you can provide,
-Ryan


Quoting Arnd Wippermann <arnd.wippermann at web.de>:

> Hello,
>
> Mapserver is capable of re-projecting. The projection of the layers (raster
> or vector data) can differ from the projection of the map. Your output comes
> in the map projection.
>
> Mit freundlichen Grüssen
>
> Arnd Wippermann
> http://gis.ibbeck.de/pinguinale/
>
>
> -----Ursprüngliche Nachricht-----
>
> I am having a bit of trouble re-projecting my data.  When I specify the
> PROJECTION object in my map file as
>
> PROJECTION
>   "proj=cc"
>   "lon_0=0"
>   "ellps=WGS84"
>   "datum=WGS84"
> END
>
> Or
>
> PROJECTION
>   "proj=cc"
>   "lon_0=90"
>   "ellps=WGS84"
>   "datum=WGS84"
> END
>
> My image does not change, but the prime meridian should be changing
> locations from the center of the image to the far left.  I also tried to
> specify the projection in the layer itself but still no change.  Isn’t
> MapServer capable of re-projecting the data regardless of the original
> projection?
>
>
>