[mapserver-users] Projection help

Jeff McKenna jmckenna at gatewaygeomatics.com
Thu Aug 1 03:19:49 PDT 2019


Next time you can prevent this grief by following the "Important Points" 
in the projections doc, when dealing with input & output projections, 
and extents: 
https://mapserver.org/mapfile/projection.html#important-notes  I often 
use these concepts for debugging issues like this.

-jeff


--

Thank you for using MS4W.
"MS4W: open doors as well as windows"


-- 
Jeff McKenna
MapServer Consulting and Training Services
https://gatewaygeomatics.com/



On 2019-07-31 11:01 PM, Ian Walberg wrote:
> Steve,
> 
> Actually that does work.
> 
> Thanks
> 
> Ian
> 
> *From:* Ian Walberg
> *Sent:* Wednesday, July 31, 2019 7:00 PM
> *To:* 'Lime, Steve D (MNIT)' <steve.lime at state.mn.us>; 
> mapserver-users at lists.osgeo.org
> *Subject:* RE: Projection help
> 
> Steve,
> 
> Good point, I did have the extent in meters but that did not work.
> 
> Should these work?
> 
> EXTENT -20026376 -20048966 20026376 20048966
> 
> Thanks
> 
> Ian
> 
> *From:* Lime, Steve D (MNIT) <steve.lime at state.mn.us 
> <mailto:steve.lime at state.mn.us>>
> *Sent:* Wednesday, July 31, 2019 6:38 PM
> *To:* Ian Walberg <ian.walberg at airborne.aero 
> <mailto:ian.walberg at airborne.aero>>; mapserver-users at lists.osgeo.org 
> <mailto:mapserver-users at lists.osgeo.org>
> *Subject:* Re: Projection help
> 
> How are you setting an extent? The default extent you’re defining is in 
> lat/lon.
> 
> ------------------------------------------------------------------------
> 
> *From:*Ian Walberg <ian.walberg at airborne.aero 
> <mailto:ian.walberg at airborne.aero>>
> *Sent:* Wednesday, July 31, 2019 5:34:05 PM
> *To:* Lime, Steve D (MNIT) <steve.lime at state.mn.us 
> <mailto:steve.lime at state.mn.us>>; mapserver-users at lists.osgeo.org 
> <mailto:mapserver-users at lists.osgeo.org> 
> <mapserver-users at lists.osgeo.org <mailto:mapserver-users at lists.osgeo.org>>
> *Subject:* RE: Projection help
> 
> 	
> 
> *This message may be from an external email source.*
> 
> Do not select links or open attachments unless verified. Report all 
> suspicious emails to Minnesota IT Services Security Operations Center.
> 
> Steve,
> 
> The map file below draws a non Mercator projection and if the epsg:4326 
> line is uncommented then the map is blank.
> 
> This is on a windows machine using Mapserver 7.0.7 from MS4W 3.2.6.
> 
> Any ideas?
> 
> Thanks
> 
> Ian
> 
> MAP
> 
> NAME global_map
> 
> STATUS ON
> 
> SIZE 1024 600
> 
> EXTENT -180 -90 180 90
> 
>   LAYER
> 
>     NAME "Earth_Vector"
> 
>     STATUS DEFAULT
> 
>     TYPE LINE
> 
>     DEBUG 3
> 
>     PROJECTION
> 
> #    "init=epsg:4326"
> 
>     END
> 
>     DATA "../shp/land/ne_110m_land.shp"
> 
>     CLASS
> 
>       STYLE
> 
>         ANTIALIAS TRUE
> 
>         COLOR 0 255 0
> 
>         WIDTH 1
> 
>       END
> 
>     END
> 
> END
> 
>    PROJECTION
> 
>      "init=epsg:3857"
> 
>    END
> 
> END #MAP END
> 
> *From:* Lime, Steve D (MNIT) <steve.lime at state.mn.us 
> <mailto:steve.lime at state.mn.us>>
> *Sent:* Wednesday, July 31, 2019 3:22 PM
> *To:* Ian Walberg <ian.walberg at airborne.aero 
> <mailto:ian.walberg at airborne.aero>>; mapserver-users at lists.osgeo.org 
> <mailto:mapserver-users at lists.osgeo.org>
> *Subject:* RE: Projection help
> 
> Should be straight forward. In the natural earth layers you’d have:
> 
> PROJECTION
> 
>      "init=epsg:4326" # geographic
> 
> END
> 
> and at the MAP level you’d have:
> 
>    PROJECTION
> 
>      "init=epsg:3857" # web mercator
> 
>    END
> 
> --Steve
> 
> *From:* mapserver-users [mailto:mapserver-users-bounces at lists.osgeo.org] 
> *On Behalf Of *Ian Walberg
> *Sent:* Wednesday, July 31, 2019 4:56 PM
> *To:* mapserver-users at lists.osgeo.org 
> <mailto:mapserver-users at lists.osgeo.org>
> *Subject:* [mapserver-users] Projection help
> 
> Hello,
> 
> We have used different projections previously but cannot get them to 
> work at the moment.
> 
> All the examples we can find online look ok but do not make any 
> difference to the generated map.
> 
> A way of projecting the Natural Earth vector country outlines as 
> Mercator would be a perfect example.
> 
> Adding  CONFIG "PROJ_DEBUG" "ON" does not appear to generate any output.
> 
> Thanks
> 
> Ian
> 
> 


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