Hello Florian, and welcome!
Le 08/03/2020 à 21:17, Florian Micklich a écrit :
I am pretty new to Apache SIS but did already some coordinate
transformations like this example:
https://sis.apache.org/book/en/developer-guide.html#CoordinateOperations
Is there also a possibility to reproject other geometries like
LineStrings and Polygons or do I have to use a CoordinateSequens to
reproject such kind of types?
Yes, but not yet with a public, committed API. The support of geometries
in Apache SIS is a work in progress. Geometries are defined by the ISO
19107 international standard, which supports up to three-dimensional
geometries with curves. JTS can been seen as a subset of that standard
for two-dimensional line strings in Cartesian space. Our plan is to
define an API based on ISO 19107, then create wrappers around JTS
objects for exposing those objects through that API. That way the same
API can also be used with ESRI API (another library which can pretty
much compete with JTS), and the API is ready for 3 dimensional objects
in the future.
But we are not yet there. In the meantime it is possible to do some
operations on JTS objects using the given class:
* org.apache.sis.internal.feature.jts.JTS
It has a static method like below:
* public static Geometry transform(Geometry geometry,
CoordinateOperation operation)
However everything in "internal" packages are not committed API; they
may change in any future SIS version. As said before we plan to provide
this service in the future through an API which work with JTS as well as
with ESRI API and future libraries. But we are not yet there and for now
that internal API is the only way.
Is there an example to do a transformation with JTS geometry with SIS?
If "source" and "target" are two EPSG code as Strings, it could be:
CoordinateReferenceSystem sourceCRS = CRS.forCode(source);
CoordinateReferenceSystem targetCRS = CRS.forCode(target);
CoordinateOperation op = CRS.findOperation(sourceCRS, targetCRS, null);
Geometry original = ...;
Geometry converted = JRS.transform(original, op); // WARNING: internal
class, may change in any future version.
Regards,
Martin
