Help: MapInfo -> PostGIS -> blank map, projection?

Daniel Caldeweyher calde at GMX.NET
Thu Jan 13 18:00:43 EST 2005


Hi,

I am using GIS on a research project for my studies and I have no
background in GIS.

I managed to bring lots of data from various sources into MapInfo, but now
I want to store all the spatial data centrally in PostreSQL / PostGIS.
I started with ogr2ogr to pipe the data directly from the TAB file to
PostGIS, which worked fine as I can use Quantum GIS to add the data as a
PostGIS layer.

However I can't get it to display anything (blank gif) with Mapserver. I am
using Apache2 + MapServer 4.4.1(pg) and it appears to be working as I can
display the "Hello World. Mapserver rocks." example.

When I export the table from MapInfo to MIF the exported file contains:
...
CoordSys Earth Projection 1, 33 Bounds (96, -45) (160, -8)
...

I also ran OGRINFO which gave me:
...
Layer name: QLDPOA_H
Geometry: Polygon
Feature Count: 405
Extent: (136.440601, -29.177898) - (153.552171, -9.142186)
Layer SRS WKT:
GEOGCS["unnamed",
    DATUM["North_American_Datum_1983",
        SPHEROID["GRS 80",6378137,298.257222101],
        TOWGS84[0,0,0,0,0,0,0]],
    PRIMEM["Greenwich",0],
    UNIT["degree",0.0174532925199433]]
...

I think the map is using long/lat + NAD83.

Other information:
In PostgreSQL the "spatial_ref_sys" table is empty.
The "geometry_columns" table contains:
19745;"''";"public";"qldpoa_h";"the_geom";"2";"-1";"MULTIPOLYGON"
The "the_geom" column in my "qldpoa_h" table has SRID=-1 for all rows

"http://localhost/cgi-bin/mapserver/mapserv.exe?map=qldpoa.map&mode=map"

My qldpoa.map file looks like this:
MAP
  SIZE 400 400
  NAME ABS
  STATUS ON

  #EXTENT 136.440601 -29.177898 153.552171 -9.142186    #from ogrinfo
  EXTENT 98 -45 160 -8      #from MIF
  UNITS dd   #kilometers?
  IMAGECOLOR 255 255 255
  IMAGETYPE gif

  LAYER
    NAME "qldpoa_h"
    TYPE POLYGON
    STATUS ON

    PROJECTION
      "proj=longlat"
      "ellps=GRS80"
      "datum=NAD83"
      "no_defs"
    END

    DATA "the_geom from qldpoa_h"
    CONNECTION "user=gis password=gis dbname=ABS host=localhost port=5432"
    CONNECTIONTYPE postgis
    CLASS
      COLOR 255 0 0
      OUTLINECOLOR 0 255 0
    END
  END

  OUTPUTFORMAT
    NAME gif
    DRIVER "GD/GIF"
    MIMETYPE "image/gif"
    IMAGEMODE PC256
    EXTENSION "gif"
  END
END

Could please someone have a look at this and tell me what I am doing wrong,
because I have tried everything I know, but I always only get a blank image.
Thank you very much in advance.



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