/// <summary>
/// Converts from source to target datum
/// </summary>
/// <param name="pt">the point containing the input and output values</param>
private void DatumTransform(Coordinate pt)
{
/* -------------------------------------------------------------------- */
/* Short cut if the datums are identical. */
/* -------------------------------------------------------------------- */
if (_sourceCRS.Datum.Equals(_targetCRS.Datum))
{
return;
}
/* -------------------------------------------------------------------- */
/* Apply grid shift if required */
/* -------------------------------------------------------------------- */
if (_sourceCRS.Datum.TransformType == Datum.Datum.DatumTransformType.GridShift)
{
_sourceCRS.Datum.ApplyGridShift(pt, false);
}
/* ==================================================================== */
/* Do we need to go through geocentric coordinates? */
/* ==================================================================== */
if (_transformViaGeocentric)
{
/* -------------------------------------------------------------------- */
/* Convert to geocentric coordinates. */
/* -------------------------------------------------------------------- */
_sourceGeoConv.ConvertGeodeticToGeocentric(pt);
/* -------------------------------------------------------------------- */
/* Convert between datums. */
/* -------------------------------------------------------------------- */
if (_sourceCRS.Datum.HasTransformToWGS84)
{
_sourceCRS.Datum.TransformFromGeocentricToWgs84(pt);
}
if (_targetCRS.Datum.HasTransformToWGS84)
{
_targetCRS.Datum.TransformToGeocentricFromWgs84(pt);
}
/* -------------------------------------------------------------------- */
/* Convert back to geodetic coordinates. */
/* -------------------------------------------------------------------- */
_targetGeoConv.ConvertGeocentricToGeodetic(pt);
}
/* -------------------------------------------------------------------- */
/* Apply grid shift if required */
/* -------------------------------------------------------------------- */
if (_sourceCRS.Datum.TransformType == Datum.Datum.DatumTransformType.GridShift)
{
_sourceCRS.Datum.ApplyGridShift(pt, true);
}
}
