OGR has support for INTERLIS reading and writing.
INTERLIS is a standard which has been especially composed in order to fulfill the requirements of modeling and the integration of geodata into contemporary and future geographic information systems. With the usage of unified, documented geodata and the flexible exchange possibilities the following advantage may occur: OGR supports INTERLIS 1 and INTERLIS 2 (2.2 and 2.3) with the following limitations:

Model support

Data is read and written into transfer files which have different formats in INTERLIS 1 (.itf) and INTERLIS 2 (.xtf). Models are passed in IlisMeta format by using "a_filename.xtf,models.imd" as a connection string.

IlisMeta files can be be generated with the ili2c compiler. Command line example:

java -jar ili2c.jar --ilidirs '%ILI_DIR;;%JAR_DIR' -oIMD --out models.imd model1.ili [model2.ili ...]
Some possible transformations using ogr2ogr.

Arc interpolation

Converting INTERLIS arc geometries to line segments can be forced by setting the configuration variable OGR_STROKE_CURVE to TRUE.

The approximation of arcs as linestrings is done by splitting the arcs into subarcs of no more than a threshold angle. This angle is the OGR_ARC_STEPSIZE. This defaults to one degree, but may be overridden by setting the configuration variable OGR_ARC_STEPSIZE.

OGR versions prior to 2.0

Arcs are always interpolated and the interpolation angle can be configured with the environment variable ARC_DEGREES.

OGR versions prior to 1.11

For using the INTERLIS model (.ili) a Java interpreter is needed at runtime and ili2c.jar (included in the Compiler for INTERLIS 2) must be in the Java path.

Other Notes