[MapServer-users] FlatGeobuf as output format

Scott public at postholer.com
Wed Jun 21 09:16:28 PDT 2023


I'm not sure how you're creating your fgb's, but from an ogr2ogr context 
try promoting all geoms to multi:

-nlt PROMOTE_TO_MULTI

On 6/21/23 07:50, Benedek Petrovicz wrote:
> Hi!
> 
> I'm trying to integrate OGR's FlatGeobuf driver as an output format in 
> my mapfiles.
> It works for the most part and it's awesome, but it fails immediately 
> when I feed some MultiPolygons into it.
> 
> The geometries are queried from an MSSQL DB.
> 
> I get the following error:
> msOGRWriteShape(): OGR error. Attempt to write feature failed (code=6): 
> ICreateFeature: Mismatched geometry type msCalculateScale(): General 
> error message. Invalid image width or height.
> 
> I found a little note in the docs which corresponds with this issue 
> (https://mapserver.org/input/vector/ogr.html 
> <https://mapserver.org/input/vector/ogr.html>):
> /"Even though MapInfo and other OGR data sources may support layers with 
> mixed geometry types (e.g. points, lines and polygons in the same file) 
> this is not yet supported in MapServer. So you still have to define a 
> layer ‘TYPE’ and make sure that all the shapes in the OGR data source 
> are compatible with that layer type, otherwise MapServer may produce an 
> error about incompatible geometry types at runtime."/
> /
> /
> So it fails for me when I have Polygons and MultiPolygons in the table 
> I'm querying.
> But it also fails if it includes MultiPolygons only. So with no mixing 
> of types.
> 
> I'm using the POLYGON type for my layer in the mapfile.
> 
> The same dataset works fine when I'm using the GML2 output format. Even 
> with mixing Polygons and MultiPolygons.
> 
> Am I doing something wrong here?
> Is it a known limitation for MultiPolygons?
> Is there a way to bypass the issue while retaining the geometries in the DB?
> 
> Thank you
> Petrovicz
> 
> _______________________________________________
> MapServer-users mailing list
> MapServer-users at lists.osgeo.org
> https://lists.osgeo.org/mailman/listinfo/mapserver-users



More information about the MapServer-users mailing list