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11

A Nested Shell is a polygon on top of another polygon. Image source


11

Yes, srsName="EPSG:abcd" is GML-3 compliant but only in an application context where EPSG:abcd points to a CRS definition. As of 2013, OGC best practice (documented here) is to use http URIs of the form http://www.opengis.net/def/crs/EPSG/0/4326. The GML-3.0.0 spec (OCG 02-023r4) section v.2, page xiv states aliasing CRSs is kosher: in GML we have found ...


9

You've caught a lot of the differences. Esri never adopted the WKIDs for the map projection algorithms or parameter names so those are all different. We didn't agree with how carefully defined the parameter definitions are. Ours are more generalized. We don't support TOWGS84 nor some of the newer keywords. When we compare strings (names), we ignore the ...


7

Normally on each OS QGIS will install the settings in a different location, however there is a switch you can start QGIS with to redirect these settings. When you start QGIS you can start it with the --optionspath and --configpath switches which you can point to a different location. QGIS will now create all the settings in a ini format and move the .qgis2 ...


7

No, GeoJSON is not an OGC standard: IETF Geographic JSON Working Group The Internet Engineering Task Force, in conjunction with the original specification authors, has formed the Geographic JSON WG to standardize the format. Work continues on GitHub at https://github.com/geojson/draft-geojson.


7

As @PolyGeo suggested, I am converting my comments into an answer. The answer is split into three parts to broadly reflect the three comments I made. Part 1 Roy Fielding's dissertation that described Representational State Transfer (REST) amongst other architectural styles Architectural Styles and the Design of Network-based Software Architectures was ...


7

Polygons are not simple to handle and there are more than two worlds. I recommend to read this article "About Invalid, Valid and Clean Polygons" http://www.springer.com/%3FSGWID%3D5-102-45-124048-p32597622 The GeoJSON specification https://www.rfc-editor.org/rfc/rfc7946 says that "GeoJSON comprises the seven concrete geometry types defined in ...


6

I don't have such a list, but going through the GDAL code will guide you: https://svn.osgeo.org/gdal/trunk/autotest/osr/osr_esri.py https://trac.osgeo.org/gdal/browser/trunk/gdal/ogr/ogr_srs_esri.cpp https://trac.osgeo.org/gdal/browser/trunk/gdal/ogr/ogr_srs_esri_names.h https://trac.osgeo.org/gdal/browser/trunk/gdal/ogr/ogrspatialreference.cpp


6

There is SLD (Styled Layer Descriptor), which I think is mainly used in OpenGIS environments. ArcGIS might have some support for it, but I have never pursued that option myself.


6

WKB presentation is defined in the OGC standards for Simple Feature Access https://www.ogc.org/standards/sfa. The details are in the document https://portal.ogc.org/files/?artifact_id=25355, Chapter 8.2.8 Description of WKBGeometry representations. This image that is taken from the standard shows the structure of the BLOB by using a polygon geometry as an ...


5

You could try an OGC Web Map Context (WMC) file. Certainly there is a WMC client extension to add WMC support to ArcGIS Desktop. The purpose of the WMC file is to bundle together web services (such as, but not limited to, ArcGIS services), such that you can share maps composed of Web Map Services to aware clients... For example the following WMC of the ...


5

If you are working with geometry types beyond the usual point/line/polygon/collection or are working with more than 2 dimensions, then yes, get the ISO spec. Otherwise, no. Also get the old OGC guidance on WKB for higher dimensions (or read the PostGIS doc) in case you're worried about maximum interoperability. (For 2d and simple geometries the new ISO stuff ...


5

dimension(): refers to the topological dimension (i.e. point/line/area) coordinateDimension(): returns the dimension of the tuple as given (as statet in the OP) spatialDimension(): returns the dimension of the tuple without the measurement part (with "M" being the measurement in a linear reference system) As it's pretty obvious for a 2D or "4D" literal, you ...


5

The QGIS client plugin is a good one - I was able to access the features of WFS without issue. ArcGIS has an interoperability connections feature that must be enabled by a user with administrator access first however I didn't try to get this working as the license is 2.5K and I don't have that license OpenLayers supports WFS as does GRASS - I found that ...


5

The Open Geospatial Consortium (OGC) exists to define interface standards such as the Web Mapping Service (WMS) standard, or Web Feature Service (WFS) standard. These are standards that define how programmers should create software to provide such a service. So for example, OGC defines the WMS standard, programmers write a piece of software called ...


5

The WMS 1.3.0 specification says in section 7.3.3.4: The mandatory STYLES parameter lists the style in which each layer is to be rendered. The value of the STYLES parameter is a comma-separated list of one or more valid style names. There is a one-to-one correspondence between the values in the LAYERS parameter and the values in the STYLES parameter. Each ...


5

If you have QGIS 3.14, press F12. Otherwise install the Network logger plugin.


4

There is no concept of zoom "levels" in the WMS specification, as there is for an XYZ/TMS. Rather, your WMS requests just use a bounding box which determines map scale.


4

Note only a GeoServer based WFS will understand a CQL filter, you can and should use an OGC Filter to achieve this effect too. You can use one (or more) of the ECQL temporal filters for this. I would probably use something like the following for your query: DATE_TIME during 2017-02-28T00:00:00Z/P1D to find all features that occurred today - the time ...


4

In my opinion, Shapefile is a good choice, but it has many limitations for historical reasons. For example, a single shapefile cannot be greater than 2GB, etc. You have to decide whether to commit to those restrictions if you use shapefile as the archival format. There is a good discussion at GIS.SE as to Are there any attempts to replace the shapefile?. ...


4

It may be an issue with your network or a temporary issue with the server, it works for me. I added http://ide.igvsb.gob.ve/geoserver/escala250000/wfs/?VERSION=1.0.0 to as the WFS url and then added your layer and got this map:


4

That is not supposed to work. SortBy is defined in the WFS 1.1.0 standard as The SORTBY parameter is used to specify a list of property names whose values should be used to order (upon presentation) the set of feature instances that satify the query. The value of the SORTBY parameter shall have the form “PropertyName [A|D][,PropertyName [A|D],…]” ...


4

After a bit of digging I found that gml:id is of type xml:ID: For both attributes and simple element content, the lexical domain of these datatypes is the lexical domain of XML nonqualified names (xs:NCName). An xs:NCName is restricted to \[\i-\[:\]\]\[\c-\[:\]\]* which means that it can't start with a number, . or minus, or contain any of the "...


4

Rules for gml:id come from the GML standard. This is about GML 3.2 7.2.4.5 id The attribute gml:id supports provision of a handle for the XML element representing a GML object. Its use is mandatory for all GML objects. <attribute name="id" type="ID"/> It is of XML type ID, so is constrained to be unique in the XML document within ...


4

WMS standard defines only how the service should work and it is assumed that every request will get an answer. How to limit the usage of the service is not in the scope of the standard. I agree with @vince that it is a general IT task. WMS clients are sending just common http GET or POST requests. However, there is at least one module that is especially ...


3

Good question and not one I've really given thought to before. This might be the sort of thing you're interested in: Some searching show's that there's ISO19123:2005 - "Geographic information -- Schema for coverage geometry and functions" - needless to say, being an ISO standard it's decidedly not "Open" - they cost a small fortune to access - http://www....


3

QGIS 2.16 brings an overhaul of the WFS provider, including WFS 1.1 and 2.0 support Source: http://qgis.org/pl/site/forusers/visualchangelog216/index.html#id96


3

You are describing what the OGC world calls a complex feature. GeoServer supports this through the App Schema plugin - see this tutorial for a (fairly) clear introduction to this.


3

Doing such a conversion (or supporting both in the same file) was a goal of GeoPackage. It isn't just a schema change though, because of different Y order conventions - you need to use a view to support both; or update all of the tile row indexes. You can try https://launchpad.net/gpkgtools (disclaimer: I'm the author) for the mbtiles to geopackage ...


3

OGC Standards are listed on the OGC Standards page. As you will see GeoJSON is not amongst them.


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