issues with scale in wms raster layers

[Travis Kirstine]

Try setting your map resolution to 96 DPI the default is 72

RESOLUTION 96

Travis

On 11/12/2007, Smith, Michael <Michael.Smith at maine.gov> wrote:
> I am trying to set up a WMS on MapServer to provide an image catalog to
> ArcGIS users (I am running latest release of MS4W on a Windows XP SP2
> box).  The problem I run into is odd behavior with setting scale
> thresholds.  I see two issues:
>
> 1)  When I set a MAXSCALEDENOM or MINSCALEDENOM property for my layer,
> the number I put it in there is not the actual min/max scale that is
> shown in ArcGIS.  Instead the scale threshold shown in ArcGIS is 4/3 the
> number I have in my .map file.  For example if I want my scale threshold
> in ArcGIS to be 50,000, I have to put 37,500 in my .map file.
>
> 2)  I have 3 layers in my .map file, two are external overview images I
> created with gdalwarp (following the steps outlined in
> http://mapserver.gis.umn.edu/docs/howto/raster_data) and the third a
> raster catalog with a tile index.  My .map file is below.  The problem
> here is that if I use the MINSCALEDENOM and/or MAXSCALEDENOM in my layer
> property for the catalog, and I include the overview images, then my
> raster catalog does not render (it shows in the layer list in my client,
> but nothing but white draws.  If I remove the overview layers from my
> .map file and try again, my catalog will work fine and honor the scale
> thresholds I set (once I adjust them as in #1 above).  If I remove the
> catalog, the two overviews work correctly.  Just not all 3.
>
> Clients I am using include ArcGIS 9.2 and Quantum GIS 0.9.  I see the
> behavior in both.
>
> Any suggestions?  Are there WMS-specific tags I should use in my
> METADATA section instead?
>
> ***********
> Michael Smith
> Maine DEP/OIT
>
> #
> # Start of GMAP map file
> #
> #
> NAME NW_DOQS
> STATUS ON
> SIZE 400 300
> SYMBOLSET ../etc/symbols.sym
> EXTENT 396000 5093000 501000 5261000
> UNITS METERS
> SHAPEPATH "../nw_doqs"
> IMAGECOLOR 255 255 255
> FONTSET ../etc/fonts.txt
>
> OUTPUTFORMAT
>  NAME JPEG
>  DRIVER "GD/JPEG"
>  IMAGEMODE RGB
>  EXTENSION "jpeg"
>  FORMATOPTION "QUALITY=75,PROGRESSIVE=TRUE"
> END
>
> OUTPUTFORMAT
>  NAME PNG8
>  DRIVER "GD/PNG"
>  MIMETYPE "image/png"
>  EXTENSION PNG
>  IMAGEMODE PC256
>  TRANSPARENT ON
> END
>
> #
> # Start of web interface definition
> #
> WEB
>  IMAGEPATH "/ms4w/tmp/ms_tmp/"
>  IMAGEURL "/ms_tmp/"
> # For WMS
>  METADATA
>    "wms_title" "nw_doqs"
>        "wms_onlineresource"
> "http://csu-eia1pcgis2.som.w2k.state.me.us/cgi-bin/mapserv.exe?map=c:/ms
> 4w/apps/gmap/htdocs/nw_doqs.map&"
>        "wms_srs" "EPSG:26919"
>  END
> END
>
> #
> # Projection - required for WMS
> #
> PROJECTION
>  "init=epsg:26919"
> END
>
> #
> # Start of layer definitions
> #
>
> LAYER
>  NAME nw_doqs100m
>  MINSCALEDENOM 375000
>  METADATA
>    "wms_title" "NW DOQs 100m overview"
>  END
>  TYPE RASTER
>  STATUS ON
>  DATA overview100.jp2
>  PROJECTION
>    "init=epsg:26919"
>  END
> END
>
> LAYER
>  NAME nw_doqs10m
>  MINSCALEDENOM 37500
>  MAXSCALEDENOM 375000
>  METADATA
>    "wms_title" "NW DOQs 10m overview"
>  END
>  TYPE RASTER
>  STATUS ON
>  DATA overview10.jp2
>  PROJECTION
>    "init=epsg:26919"
>  END
> END
>
> LAYER
>  NAME nw_doqs
>  MAXSCALEDENOM 37500
>  METADATA
>    "wms_title" "NW DOQs"
>  END
>  TILEINDEX "nw_doqs_index.shp"
>  TILEITEM "location"
>  TYPE RASTER
>  STATUS ON
>  PROJECTION
>    "init=epsg:26919"
>  END
> END
>
> END # Map File
>


-- 
Travis K.

Toronto, Canada
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"She knows there's no success like failure
And that failure's no success at all."
-Bob Dylan-
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