Le lundi 23 juin 2014 03:32:32, Jeremy Palmer a écrit : > I'm querying an ArcGIS service obtain polygon data, however the service > seems to define Island multi-polygons objects as single polygons with > multiple exterior rings. This creates invalid OGC geometries and is > causing processing problems in my workflow. > > He's the service and a validation test showing the polygon is not valid: > > ogrinfo -dialect sqlite -sql "SELECT TA2013_V1_00_NAME, > ST_IsValid(GEOMETRY) FROM OGRGeoJSON" > http://maps.stats.govt.nz/wss/service/arcgis1/guest/Boundaries/2013_Geogra > phies/MapServer/9/query?f=json&objectIds=36&returnGeometry=true&outSR=4167 > > GEOS warning: Hole lies outside shell at or near point 174.78189611685229 > -41.077770200471164 > > Layer name: SELECT > Geometry: None > Feature Count: 1 > Layer SRS WKT: > (unknown) > TA2013_V1_00_NAME: String (0.0) > ST_IsValid(GEOMETRY): Integer (0.0) > OGRFeature(SELECT):0 > TA2013_V1_00_NAME (String) = Porirua City > ST_IsValid(GEOMETRY) (Integer) = 0 > > Is this a bug in the data from the service, or just the way the Esri > defines geometry objects (and therefor an OGR bug)? I can't see a > definition for multi-polygons in Esri API docs: > > http://resources.arcgis.com/en/help/arcgis-rest-api/index.html#//02r3000000 > n1000000
Looking at the ogresrijsonreader.cpp code I can see I assumed that a esriPolygon was just a OGC Polygon, so with outer ring first and then inner rings. Fixing the code to support multi polygons should basically be a matter of calling OGRGeometryFactory::organizePolygons. Even -- Geospatial professional services http://even.rouault.free.fr/services.html _______________________________________________ gdal-dev mailing list gdal-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/gdal-dev
