Terraservice data not aligning

[Gregory S. Williamson]

Camden --

If you have only a few areas of concern it is possible to edit TIGER data ... I have converted a TIGER set into a shapefile and the used the JUMP program to  make adjustments and fill in missing data. Obviously this is not practical if you need to serve many counties, but on a "retail" basis this approach works, at least until you get new street data.

I have found that the quality of the TIGER data varies from fairly good ("good enough for government work" ?) to fair, depending on the region. The new release of TIGER data will be improved but obviously won't be happening immediately.

Greg Williamson
DBA
GlobeXplorer LLC

-----Original Message-----
From:   Camden Daily [mailto:cdaily at GMAIL.COM]
Sent:   Mon 1/3/2005 8:00 AM
To:     MAPSERVER-USERS at LISTS.UMN.EDU
Cc:	
Subject:        [UMN_MAPSERVER-USERS] Terraservice data not aligning
Hello all.  I've got a layer in my map file that I'm grabbing from
terraservice, and it's mostly working great.  However, when I overlay
some Tiger/Line street data over the terraserver image, things aren't
quite lining up.  It's very, very close, but just slightly offset when
zoomed in (maybe by 20-50 feet).

My map file, the terraservice layer, and the tiger/line data are all
projected as EPSG:4326, so I don't think it's a projection issue.  Has
anyone else experienced any issues mixing these two data sets?

Is it possible to 'tweak' a layer so that it's offset by a short
distance?  I know about the 'offset' parameters for styles, but those
only take units of pixels (which will look good at some zoom levels,
but not others...)  I'd be grateful for any suggestions.

-Camden Daily

terraserver layer:

  LAYER
    NAME "aerial"
    TYPE RASTER
    STATUS OFF
    MINSCALE 1000 # trying to grab too small a scale might result in
an error from terraservice
    CONNECTIONTYPE WMS
    CONNECTION
"http://terraservice.net/ogcmap.ashx?VERSION=1.1.1&SERVICE=wms&LAYERS=urbanarea&FORMAT=image/jpeg&STYLES="
    METADATA
     "wms_srs" "EPSG:4326"
    END
    PROJECTION
      "init=epsg:4326"
    END
  END

tiger/line layer:

  LAYER
    NAME "aerial_road_small_near"
    TYPE LINE
    STATUS OFF
    DATA "tgr17031lkA"
    MAXSCALE 100000
    CLASSITEM "CFCC2"
    CLASS
      EXPRESSION /A4|A5|A6|A7/
      COLOR 150 150 150
    END
    PROJECTION
      "init=epsg:4326"
    END
  END