[mapserver-users] Why CRS bounding boxes do not suit?

[Rahkonen Jukka (Tike)]

Hi,

I wonder what goes wrong with calculating the extra bounding boxes into WMS GetCapabilities. For example here I have set the wms_extent in the layer metadata as "wms_extent" "19970 6597278 749676 7785300" in EPSG:3067 units.

Let's check the corresponding values in EPSG:2393
cs2cs +init=epsg:3067 +to +init=epsg:2393
19970  6597278
3019946.27      6600051.87 -28.59
749676 7785300
3749949.38      7788549.07 -22.66

Compare with the WMS 1.3.0 GetCapabilities.  Only thing that seems to be correct in the <BoundingBox CRS lines is the minx miny in EPSG:3067 that equals to what I gave in the metadata.  But the EPSG:3067 maxx maxy is not what I gave and EPSG:2393 bbox is all wrong. For example the max  northing is announced to be 9852820 while it should be 7788549. Difference is more than 2000 km which is too much for a rounding error.

By the way, when looking at the numbers it is good to know that EPSG:2393 is x=northing, y=easting system.

<EX_GeographicBoundingBox>
<westBoundLongitude>15.7669</westBoundLongitude>
<eastBoundLongitude>33.1499</eastBoundLongitude>
<southBoundLatitude>59.528</southBoundLatitude>
<northBoundLatitude>70.0976</northBoundLatitude>
</EX_GeographicBoundingBox>
<BoundingBox CRS="EPSG:2393" minx="6.62653e+06" miny="3.0678e+06" maxx="9.85282e+06" maxy="3.73477e+06"/>
<BoundingBox CRS="EPSG:3067" minx="68000" miny="6.62375e+06" maxx="734502" maxy="7.77675e+06"/>
<BoundingBox CRS="EPSG:4326" minx="59.528" miny="15.7669" maxx="70.0976" maxy="33.1499"/>
<BoundingBox CRS="EPSG:3857" minx="1.75517e+06" miny="8.29539e+06" maxx="3.69023e+06" maxy="1.11005e+07"/>

-Jukka Rahkonen-