MathTransform.Transform modifies the original ICoordinateSequence

[kshahar]

This issue affects NetTopologySuite GeometryTransform. To reproduce:

var geometryServices = new NtsGeometryServices();
var geometryFactory = geometryServices.CreateGeometryFactory();

var coordinateTransformationFactory = new CoordinateTransformationFactory();
var transform = coordinateTransformationFactory.CreateFromCoordinateSystems(
    GeographicCoordinateSystem.WGS84,
    GeocentricCoordinateSystem.WGS84
);

var sequence = geometryFactory.CoordinateSequenceFactory.Create(
    new[] { new Coordinate(-75.212144, 39.952874, 1000) });
var convertedSequence = transform.MathTransform.Transform(sequence);
Console.WriteLine("Original : {0}\nConverted: {1}", sequence, convertedSequence);

Output:

Original : ((1249872.4843066079, -4734640.5686484585, 4074617.9450782747))
Converted: ((1249872.4843066079, -4734640.5686484585, 4074617.9450782747))

[terribletim]

Method summaries on the various transform methods in GeoAPI.CoordinateSystems.Transformations.IMathTransform say words to the effect of The input remains unchanged.

The implementation in ProjNet4GeoApi does not adhere to this.

Please are the project owners able to decide how to resolve this?

Current implementation does not lend itself to any easy choice! Would it be better to add new methods to clearly support preserving or modifying input coordinates?