Geography Markup Language (GML) is an OGC Standard for expressing geographical features.

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12
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6answers
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What's an efficient way of detecting road junctions on a map?

I may receive maps from any source for my project, and for the C++ algorithm I'm making, it's imperative for the algorithm to know where road junctions (nodes where more than two road segments meet) ...
10
votes
3answers
428 views

What does it mean “GML is an XML grammar”?

I'm trying to get my head around the theoretical side of XML and GML. The OGC web page for GML states that: The Geography Markup Language (GML) is an XML grammar for expressing geographical ...
10
votes
5answers
4k views

GML, KML, GeoJSON - Speed rendering 3109 polygons?

I am working with Geoserver, serving U.S. Lower 48 counties to openlayers (3109 polygons - lots more vertices). The counties are loaded into a postgis database. I am curious about developer ...
10
votes
2answers
1k views

Why does one part of GML -> KML conversion not work on Google Maps?

Brand new to all of this, not even sure this is the right forum to ask in... I have a client who wants to visualise cancer incidence and mortality rates by local/unitary authority across Great ...
9
votes
2answers
1k views

Storing GML surface in PostGIS

I'm using PostGIS 2.0.0 and would like to store a GML Surface in a way that allows calculating intersections between that surface and various points and lines. In my case, the Surface will have one ...
8
votes
4answers
7k views

How do I use ogr2ogr to convert a GML to shapefile in Python

I am trying to convert a GML to an ESRI shapefile using ogr2ogr utility in a python script. I have successfully installed the GDAL/OGR package via osgeo but I am now struggling to find/understand ...
8
votes
3answers
4k views

How to write GML with Geotools?

I'd like to write GML using Geotools. Unfortunately, I can't find documentation on a GML Writer (except for this one from 2006: http://docs.codehaus.org/display/GEOTOOLS/WFS+++GML+DataStore). Could ...
8
votes
2answers
3k views

Why can't I edit KML/GML layers?

Newbie here confused by my first experience in QGIS I have a handful of lines defining a bike route. Originally they were saved in a .gml file and later translated into .kml so they could be viewed ...
7
votes
3answers
5k views

How to import/export geographic information (gml or csv file) to geodatabase?

I am searching for C#/Java libraries that can import and export geographic information (gml/csv file formats) from and to geodatabases. If not yet available, is there other way to do this task? Any ...
7
votes
2answers
4k views

How to convert GML Surface to SHP Using OGR?

I have a very large .gml file with multiple layers in it. I would like to export one of these layers to .shp. It is a polygon layer (of lakes). However, I am getting the error: ERROR 1: ...
7
votes
5answers
937 views

Tutorials for UML/GML

Do you know any good tutorials or any resources for learning from the beginning UML and GML ? I am asking because (later) i would like to learn how to make a application schemas in context of ...
5
votes
3answers
4k views

Convert GML to GeoJSON

I have downloaded a GML file from Statistics Canada and would like to convert it into GeoJSON to use parts of it in a D3 visualization on the web. However, I did not find a converter that would do ...
5
votes
1answer
375 views

Experience with Geoserver's GML Extension

I'd like to know if Geoserver's GML extension works (well) with GeoServer 2.1-RC2 and whether it will enable uploading of GML files via REST API.
5
votes
1answer
333 views

How to convert WFS request to GML

I have the following: var popProto = new OpenLayers.Protocol.WFS({ url: WFS_HOST, version: "1.1.0", featureType: layerName, featureNS: namespace, srsName: "EPSG:4326", ...
5
votes
1answer
643 views

How to add GML files in geoserver 2.2.2?

How can I add GML files to a GeoServer 2.2.2 instance? How can edit them "on the fly" and save the results back to the server using OpenLayers? I would appreciate examples if possible. I'm adding a ...
4
votes
4answers
706 views

Looking for web and desktop tools with GML support

I am a graduate student and a novice in GIS field. I have few GML files that contain vector polygon data and I want to see them in a map format. The problem is that I do not have access to ...
4
votes
4answers
2k views

What are the advantages either way between GML and Shapefiles?

After a good start many months ago of getting into GIS through QGIS, I had to drop what I was doing and did not touch it for quite some time. I am now able to get back into it and have a need to load ...
4
votes
1answer
128 views

What is the best format to encode polygons such as lakes?

I am looking for a standard format to encode polygons, such as lakes, in one file that is easy to create and common so that others can use it in different GIS systems. Every file will contain data on ...
4
votes
1answer
642 views

Is there an XML equivalent to GeoJSON?

In my web application, I am retrieving geospatial data from a server backend (Java) to the browser frontend (JavaScript). I am considering two options of how to serialize the data in this ...
4
votes
2answers
6k views

WFS Request Layer (GML) with Filter

Is there a solution to request the GML layer from Geoserver with filter like using bbox: http://localhost:8080/geoserver/tiger/ows?service=WFS&version=1.0.0 ...
4
votes
2answers
207 views

Is it valid GML if the boundary of a polygon intersects itself?

Is it valid GML if the boundary of a polygon intersects itself? E.g. I have this polygon consisting of some gml:LineStingSegment and one gml:Arc: My task is to import GML based data (german ALKIS ...
4
votes
2answers
72 views

Modelling per-segment attributes in GML LineString

This is not a software-specific question, but rather a question about how to represent some concepts in a GML LineString. It has to be GML, for policy reasons. Consider a GML LineString consisting ...
4
votes
1answer
740 views

Why are the polygons in my GML not rendered?

I tried to view GML files from download services ( http://services.cuzk.cz/gml/inspire/cp/epsg-5514/ ) and I have a problem with viewing of polygons from layer "CP:CadastralParcel". This Layer ...
4
votes
8answers
6k views

Getting OS Mastermap data into QGIS?

I have been tasked with getting OS Mastermap topography data into QGIS system to compliment our other map layers. The data comes in .gz format. Which I am told needs to be decompressed before I can do ...
4
votes
1answer
693 views

How to use the OGR/GDAL configure options in QGIS python environment

I’m looking for a solution how to use the OGR/GDAL configure options (--config) in the qgis python environment. http://trac.osgeo.org/gdal/wiki/ConfigOptions Setting special configure options is ...
4
votes
1answer
434 views

How to get a GML overlay on Google Maps?

Anyone know how to get a GML file to show as an overlay on Google Maps? To be honest I don't know my GML from my KML, or my ETRS89 from my WGS84, as this topic is completely new to me. A bit of ...
4
votes
2answers
317 views

Read an INSPIRE GML in QGIS2.0 : gml:xlink resolving

I'm trying to read an INSPIRE GML, which contains internal and external links between the elements. I saw on the GDAL site that we can set environment variable in order to load this link in QGIS ...
4
votes
1answer
214 views

Linux Tool to visualize CityGML file

I am looking for a linux program that allows me to visualize CityGML models (3D). I have tried a whole bunch so far (most of them via wine but also native ones) but I couldn't get a single one of them ...
4
votes
0answers
268 views

PostGIS 2.0 st_geomfromgml using LineString fails with invalid GML representation

I am attempting to insert a geometry into a table using the st_geomfromgml function. The GML is being sourced from a Geoserver WFS request. The function call looks like this ...
4
votes
0answers
323 views

Can GeoTools parse GML CRS definitions?

A kind of branching of this question. Soon I will need to handle GML Coordinate Reference Sysyem definitions in a Java servlet. Links: GML OGC reference. Concrete example. I know that GeoTools ...
4
votes
0answers
671 views

Why doesn't the gml 3.1.1 schema validate with xmllint?

Running xmllint on the gml 3.1.1 schema fails, even though the release notes claim that this release was created to get the schema to validate using 'common tools'. There's questions about this on ...
3
votes
2answers
127 views

Is GeoJSON an OGC format

I am using geometries in a JavaScript page and it is best to use JSON objects rather than GML which is XML based. I heard of GeoJSON, but is it an OGC open format?
3
votes
2answers
731 views

Remove unneeded columns from geographic data file?

I have some GML data that has some unneeded columns in it. I'd like to remove these columns in order to reduce the file size. (To clarify: I mean that the file has many points in it, and each of these ...
3
votes
2answers
9k views

How do I convert GML to ESRI featureclasses?

I have a series of xml files containing gml tags such as : <gml:posList srsDimension="2">454780.3125 525867.9375 454762.0625 525994.5625 and I need to convert these into esri featureclasses. ...
3
votes
1answer
466 views

Python: shp file to GML using OGR

I am trying to convert a shapefile to GML 3.1.1 . I am using gdal 1.9.1 however the GML conversion it generates for a geometry feature is GML 2 and it also swaps the long/latitude coordinates. Are ...
3
votes
1answer
355 views

How to show one to many relationships in GML from GeoServer/Postgis?

I am just figuring out how to use GeoServer and Postgis. I am using the States.shp example that came with GeoServer, and I have uploaded that into a table into the Postgis database. I have created a ...
3
votes
1answer
303 views

Polygon Shared Boundaries in GML

Last week I was told on a phone conference that GML supports shared boundaries in Polygon's. I have been unable to find any documenatation to substantiate the claim. Here is the situation: I have a ...
3
votes
1answer
603 views

Is there a Java library to load data from a WFS server?

I am writing a java client to display remote GIS data. I want to load data provided in GML by a WFS server. Do you know a java library I could use for that?
3
votes
1answer
2k views

OpenLayers.Format.GML.parseFeature() with GML v3 data

I have a partial GML object with the geometry type polygon. The GML version must be 3+ since the coordinates are wrapped in the gml:posList tag: <gml:Polygon srsName="EPSG:25832" ...
3
votes
1answer
508 views

How to write GML parser with Geotools?

I wrote a Parser for a GML file from the OS Mastermap with geotools 8.4. With one part I still have a problem. This sniplet of the xsd: <complexType name="RoadLinkType"> ...
3
votes
1answer
290 views

How can I get KML into JTS TestBuilder?

JTS Topology Suite TestBuilder supports WKT, WKB and GML inputs. What's a quick and easy way to get the geometry for a KML feature into one of these formats for input into JTS TestBuilder? For ...
3
votes
1answer
646 views

How to write GML and GeoJSON features while retaining attributes in .NET?

I am developing a .NET project [C#] that needs to export/write features as GML and GeoJSON, including, of course, the attributes; data could queried by a database or manually entered. I checked ...
3
votes
1answer
518 views

How to couple GeoTools GML bindings for encoding to GML 3.1.1

I've successfully created GeoTools (8.3) bindings for parsing and encoding XML bindings as described in their tutorial: http://docs.geotools.org/latest/userguide/library/xml/internal/bindings.html I ...
3
votes
1answer
514 views

OSS java approach to convert Shapefile to GML

We've got a project coming up where we need to upload .zip of a shapefile, join the .dbf to some lookup tables, join to other tables also uploaded (one to many attributes for each feature), and ...
3
votes
1answer
717 views

PostGIS: ST_Transform function conversion problem

I'm inserting map data from a GML file with srid EPSG:27700 into a PostGIS database table with srid EPSG:4326. I'm using the ST_Transform function as in this snippet: ...
3
votes
0answers
37 views

QGIS won't display GML features

I have a 90 MB GML with about 3000 features but QGIS only shows the first three. The fourth feature is a multipart polyline. This an the extract of the feature: <?xml version="1.0" ...
3
votes
0answers
42 views

ogr2ogr imports GML data (not from OSM) to Postgis but without the other_tags “hstore”-column

The problem I'm encountering some issue trying to use ogr2ogr to import some GML input data (not OSM) into Postgres. I'm trying to use COLUMN_TYPES=other_tags=hstore to store all the fields not ...
3
votes
0answers
913 views

What is the best way to convert WKT String to GML String

What is the best way to programatically convert WKT String to GML String? Every reasonable library (at best available in some Maven repository) can be used. Till now I came up with this solution ...
2
votes
4answers
2k views

GML Parser for C++/Java/…?

I am looking for a good parser for the latest GML (Geographic Markup Language) version in preferably: C++/Java/Ruby/... I am especially interested in reading the geometry of individual features. Does ...
2
votes
1answer
857 views

how to download a file from geoserver gml from a url using javascript?

how to download a file from geoserver gml from a url using javascript? I'm doing a web application with javascript, but I could not download files from geoserver, the url given entry does not bring ...