Hi!
I would like to transform Coordinates from EPSG:4326 to EPSG:3035.
My aim is to calculate the area of a polygon and 3035 is area true.
The suggested solution on the geotools website is following:
DefaultFactory df = (DefaultFactory) FactoryFinder.getCRSAuthorityFactory("EPSG",new Hints(Hints.CRS_AUTHORITY_FACTORY, DefaultFactory.class));
CoordinateReferenceSystem sourceCRS = df.createCoordinateReferenceSystem("EPSG:4326");
CoordinateReferenceSystem targetCRS = df.createCoordinateReferenceSystem("EPSG:3035");
CoordinateOperationFactory coFactory = FactoryFinder.getCoordinateOperationFactory(null);
CoordinateOperation op = coFactory.createOperation(sourceCRS, targetCRS);
MathTransform oMathTransformer = op.getMathTransform();
Feature f = ...
Geometry oGeometry = f.getGeometry();
oGeometry = JTS.transform(oGeometry,oMathTransformer);
I included the epsg-hsql library in the classpath which also includes the required Bursa-Wolf-Parameter for the Datum-Shift (if I understood correct)
I calculated so the area for Germany and became a completly wrong result >> 5.5E11 instead of 3.5E11
If I do the same calculation based on the epsg-wkt library (what is not recommended) which does NOT include the required Bursa-Wolf-Parameter for the Datum-Shift I get the correct result for the calculated area!
I set the Hints.LENIENT_DATUM_SHIFT:
EPSGCRSAuthorityFactory ef = new EPSGCRSAuthorityFactory();
CoordinateReferenceSystem sourceCRS = ef.createCoordinateReferenceSystem(codeSource);
CoordinateReferenceSystem targetCRS = ef.createCoordinateReferenceSystem(codeTarget);
Hints hints = new Hints(Hints.LENIENT_DATUM_SHIFT, Boolean.TRUE);
CoordinateOperationFactory coFactory = FactoryFinder.getCoordinateOperationFactory(hints);
CoordinateOperation op = coFactory.createOperation(sourceCRS, targetCRS);
...
Am I doing something wrong in the hsql solution???
Thanks for your help!
Beate
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