Hello Clay
Le 17/03/2021 à 18:10, Clay Harter a écrit :
I see how I may get a CoordinateOperation to convert from one CRS to
another in a given area of interest by calling
CRS.findOperation(sourceCRS, targetCRS, areaOfInterest) . But in the
case where the source and target CRS have different datum there may be
multiple transforms available. If I know the EPSG code of the
transform (datum shift) I wish to use how may I assert it? In this
case I don’t want SIS to pick it for me.
This is the work of CoordinateOperationAuthorityFactory. An example is
below. The first line is a bit of cheating, more on it below.
import org.opengis.referencing.operation.CoordinateOperationAuthorityFactory;
(...snip...)
CoordinateOperationAuthorityFactory opFactory = (CoordinateOperationAuthorityFactory)
CRS.getAuthorityFactory("EPSG");
CoordinateOperation op = opFactory.createCoordinateOperation("1172");
System.out.println(op);
The CRS.getAuthorityFactory(…) method is for fetching a
CRSAuthorityFactory. We do not have a public method for fetching the
CoordinateOperationAuthorityFactory at this time, but it appears that in
the particular case of Apache SIS, the implementation class of
CRSAuthorityFactory also implements all other authority factory
interfaces. We will provide methods for factories of all types in some
future SIS version (it is pending an update of GeoAPI interfaces).
Martin
