/// <summary>
///
/// </summary>
/// <param name="points"></param>
/// <param name="source"></param>
/// <param name="dest"></param>
/// <param name="startIndex"></param>
/// <param name="numPoints"></param>
public static void ReprojectPoints(double[][] points, ProjectionInfo source, ProjectionInfo dest, int startIndex, int numPoints)
{
double toMeter = source.Unit.Meters;
// Geocentric coordinates are centered at the core of the earth. Z is up toward the north pole.
// The X axis goes from the center of the earth through greenwich.
// The Y axis passes through 90E.
// This section converts from geocentric coordinates to geodetic ones if necessary.
if (source.IsGeocentric)
{
if (points[0].Length < 3)
{
throw new ProjectionException(45);
}
for (int i = startIndex; i < numPoints; i++)
{
if (toMeter != 1)
{
points[i][0] *= toMeter;
points[i][1] *= toMeter;
}
}
GeocentricGeodetic g = new GeocentricGeodetic(source.GeographicInfo.Datum.Spheroid);
g.GeocentricToGeodetic(points, startIndex, numPoints);
}
// Transform source points to lat/long if they are not already
if (!source.IsLatLon)
{
ConvertToLatLon(source, points, startIndex, numPoints);
}
double fromGreenwich = source.GeographicInfo.Meridian.Longitude * source.GeographicInfo.Unit.Radians;
if (fromGreenwich != 0)
{
for (int i = startIndex; i < numPoints; i++)
{
if (points[i][0] != double.PositiveInfinity)
{
points[i][0] += fromGreenwich;
}
}
}
// TO DO: DATUM TRASNFORM IF NEEDED
// Adjust to new prime meridian if there is one in the destination cs
fromGreenwich = dest.GeographicInfo.Meridian.Longitude * dest.GeographicInfo.Unit.Radians;
if (fromGreenwich != 0)
{
for (int i = startIndex; i < numPoints; i++)
{
if (points[i][0] != double.PositiveInfinity)
{
points[i][0] -= fromGreenwich;
}
}
}
if (dest.IsGeocentric)
{
if (points[0].Length < 3)
{
throw new ProjectionException(45);
}
GeocentricGeodetic g = new GeocentricGeodetic(dest.GeographicInfo.Datum.Spheroid);
g.GeodeticToGeocentric(points, startIndex, numPoints);
double frmMeter = 1 / dest.Unit.Meters;
if (frmMeter != 1)
{
for (int i = startIndex; i < numPoints; i++)
{
if (points[i][0] != double.PositiveInfinity)
{
points[i][0] *= frmMeter;
points[i][1] *= frmMeter;
}
}
}
}
else
{
if (!dest.IsLatLon)
{
ConvertToProjected(dest, points, startIndex, numPoints);
}
}
}
private static void DatumTransform(ProjectionInfo source, ProjectionInfo dest, double[][] points, int startIndex, int numPoints)
{
Spheroid wgs84 = new Spheroid(Proj4Ellipsoids.WGS_1984);
Datum sDatum = source.GeographicInfo.Datum;
Datum dDatum = dest.GeographicInfo.Datum;
double[][] zPoints = new double[points.Length][];
bool zIsTemp = false;
/* -------------------------------------------------------------------- */
/* We cannot do any meaningful datum transformation if either */
/* the source or destination are of an unknown datum type */
/* (ie. only a +ellps declaration, no +datum). This is new */
/* behavior for PROJ 4.6.0. */
/* -------------------------------------------------------------------- */
if (sDatum.DatumType == DatumTypes.Unknown ||
dDatum.DatumType == DatumTypes.Unknown)
{
return;
}
/* -------------------------------------------------------------------- */
/* Short cut if the datums are identical. */
/* -------------------------------------------------------------------- */
if (sDatum.Matches(dDatum))
{
return;
}
double srcA = sDatum.Spheroid.EquatorialRadius;
double srcEs = sDatum.Spheroid.EccentricitySquared();
double dstA = dDatum.Spheroid.EquatorialRadius;
double dstEs = dDatum.Spheroid.EccentricitySquared();
/* -------------------------------------------------------------------- */
/* Create a temporary Z value if one is not provided. */
/* -------------------------------------------------------------------- */
if (points[0].Length > 2)
{
zPoints = points;
}
else
{
for (int i = startIndex; i < numPoints; i++)
{
zPoints[i] = new[] { points[i][0], points[i][1], 0 };
}
zIsTemp = true;
}
/* -------------------------------------------------------------------- */
/* If this datum requires grid shifts, then apply it to geodetic */
/* coordinates. */
/* -------------------------------------------------------------------- */
if (sDatum.DatumType == DatumTypes.GridShift)
{
// pj_apply_gridshift( pj_param(srcdefn->params,"snadgrids").s, 0,
// point_count, point_offset, x, y, z );
GridShift.Apply(source.GeographicInfo.Datum.NadGrids, false, points, startIndex, numPoints);
srcA = wgs84.EquatorialRadius;
srcEs = wgs84.EccentricitySquared();
}
if (dDatum.DatumType == DatumTypes.GridShift)
{
dstA = wgs84.EquatorialRadius;
dstEs = wgs84.EccentricitySquared();
}
/* ==================================================================== */
/* Do we need to go through geocentric coordinates? */
/* ==================================================================== */
if (srcEs != dstEs || srcA != dstA ||
sDatum.DatumType == DatumTypes.Param3 ||
sDatum.DatumType == DatumTypes.Param7 ||
dDatum.DatumType == DatumTypes.Param3 ||
dDatum.DatumType == DatumTypes.Param7)
{
/* -------------------------------------------------------------------- */
/* Convert to geocentric coordinates. */
/* -------------------------------------------------------------------- */
GeocentricGeodetic gc = new GeocentricGeodetic(sDatum.Spheroid);
gc.GeodeticToGeocentric(zPoints, startIndex, numPoints);
/* -------------------------------------------------------------------- */
/* Convert between datums. */
/* -------------------------------------------------------------------- */
if (sDatum.DatumType == DatumTypes.Param3 || sDatum.DatumType == DatumTypes.Param7)
{
// pj_geocentric_to_wgs84( srcdefn, point_count, point_offset,x,y,z);
}
if (dDatum.DatumType == DatumTypes.Param3 || dDatum.DatumType == DatumTypes.Param7)
{
// pj_geocentric_from_wgs84( dstdefn, point_count,point_offset,x,y,z);
}
/* -------------------------------------------------------------------- */
/* Convert back to geodetic coordinates. */
/* -------------------------------------------------------------------- */
gc = new GeocentricGeodetic(dDatum.Spheroid);
gc.GeodeticToGeocentric(zPoints, startIndex, numPoints);
}
/* -------------------------------------------------------------------- */
/* Apply grid shift to destination if required. */
/* -------------------------------------------------------------------- */
if (dDatum.DatumType == DatumTypes.GridShift)
{
// pj_apply_gridshift( pj_param(dstdefn->params,"snadgrids").s, 1,
// point_count, point_offset, x, y, z );
GridShift.Apply(dest.GeographicInfo.Datum.NadGrids, true, points, startIndex, numPoints);
}
if (zIsTemp)
{
for (int i = startIndex; i < numPoints; i++)
{
points[i][0] = zPoints[i][0];
points[i][1] = zPoints[i][1];
}
}
}