GML (Geography Markup Language) Reader/Writer

Licensing options for this format begin with FME Professional Edition.

The GML Reader/Writer allows FME to read and write files in the Geography Markup Language (GML) format.

Note: This chapter assumes familiarity with the GML format.

Overview

GML is an OpenGIS® Implementation Specification. The GML specification defines an XML encoding for the transport and storage of geographic information. This specification can be found at the Open GIS Consortium website www.opengeospatial.org.

GML documents must be instances of a conforming application schema. Conforming application schemas are to be defined with the W3C’s XML Schema language.

Versions

Reader: GML v2.1.2, v3.1.1, v3.2.1 files, and application schema.

Writer: GML v3.1.1, v3.2.1 files, and application schema.

Reader Overview

Multi-value properties (that is, declared with a maxOccurs that is greater than 1 or unbounded) are supported and are mapped into list attributes. Null values are not read unless they are nillable.

GML properties that are defined as complex types are supported – these complex properties are mapped as structured list attributes.

This reader supports multiple geometry properties per feature type: see the Map Geometry Columns reader parameter.

Writer Overview

The GML writer may either write to an existing GML Application Schema, or output a dataset and a schema document corresponding to the GML writer’s feature type definitions. To generate GML based solely on the feature type definitions, the GML Version parameter must be set to 3.1.1 (which is the default) or 3.2.1.

The GML application schema structure is controlled by the GML writer’s user attributes. The writer will create an XSD that is based on the writer feature type definitions, in the same folder and with the same file basename as the output dataset. Two XML documents are written: a GML instance document, and its corresponding GML application schema.

To write to an existing GML Application Schema, the writer’s GML Version parameter must be set to Application Schema, and a valid accessible GML application schema provided in the Application Schema parameter (local file path or URL). In this mode, the GML writer will write a single GML dataset file corresponding to an existing GML Application Schema. No XSD will be written.

Additional GML Formats

FME supports these additional GML formats:

Format Name

FME Short Name

AIXM 5.x (Aeronautical Information Exchange Model GML) Reader/Writer

AIXM5

BC MoF Electronic Submission Framework (ESF) Reader/Writer ESF
CityGML Reader/Writer CITYGML

CUZK_GML (Czech Republic) Reader

CUZK_GML

Dutch Top10 GML Reader/Writer

TOP10

Dutch TOP50NL GML Reader

TOP50NL

German AAA GML Exchange Format (NAS) Reader

NAS (ALKIS)
GML SF-0 (Geography Markup Language Simple Features Level SF-0 Profile) Reader/Writer GMLSF
GML v2.1.2 (Geography Markup Language) Reader/Writer GML2, GML212
HERE Venue Map (GML) Reader/Writer HERE_VENUE_MAP
IndoorGML Reader/Writer INDOORGML

INSPIRE GML Reader/Writer

INSPIRE

JPEG 2000 (GeoJP2/GMLJP2) Reader/Writer JPEG2000

KommunGML (Sweden) Reader

KOMMUNGML

KuntaGML (Finland) Reader

KUNTAGML

NEN 3610 (GML) Reader

NEN3610

NLSF Topographic GML (MTKGML) Reader

MTKGML
OS (GB) MasterMap DNF
OS VectorMap District Reader OSVECTORMAPDISTRICT
OS VectorMap Local Reader OSVECTORMAPLOCAL

SeabedML (GML) Reader/Writer

SEABEDML
SOSI GML Reader/Writer SOSI_GML
Swedish I2K/G2K (Interface 2000 GML) Reader/Writer I2KGML
Swiss INTERLIS (ili2fme) Reader/Writer CH.EHI.FME.MAIN

U.S. Census Bureau TIGER/GML Reader

TIGERGML