Projects a geometry, optionally applies a GeoTransformation, and optionally densifies the geometry.
[Visual Basic .NET] Public Sub ProjectEx ( _ ByVal newReferenceSystem As ISpatialReference, _ ByVal direction As esriTransformDirection, _ ByVal GeoTransformation As IGeoTransformation, _ ByVal bAngularDensify As Boolean, _ ByVal maxSegmentLength As Double, _ ByVal maxDeviation As Double _ )
[C#] public void ProjectEx ( ISpatialReference newReferenceSystem, esriTransformDirection direction, IGeoTransformation GeoTransformation, bool bAngularDensify, double maxSegmentLength, double maxDeviation );
[C++]
HRESULT ProjectEx(
ISpatialReference* newReferenceSystem,
esriTransformDirection direction,
IGeoTransformation* GeoTransformation,
VARIANT_BOOL bAngularDensify,
double maxSegmentLength,
double maxDeviation
);
[C++]Parameters
newReferenceSystemnewReferenceSystem is a parameter of type ISpatialReference
directiondirection is a parameter of type esriTransformDirection
GeoTransformationGeoTransformation is a parameter of type IGeoTransformation
bAngularDensify bAngularDensify is a parameter of type VARIANT_BOOL maxSegmentLength maxSegmentLength is a parameter of type double maxDeviation maxDeviation is a parameter of type double
Product Availability
Errors Returned
Run-time Error: 430 Class does not support Automation or does not support expected interface
This error will be produced when IGeometry2::ProjectEx is used on a GeometryBag which contains segments: BezierCurve, CircularArc, EllipticArc, Line. Segments do not implement IGeometry2. To avoid this restriction convert the segment into a Polyline before adding it to the GeometryBag.
Remarks
By default, ProjectEx will not densify geometries as they are projected. This can lead to the output geometries not reflecting the 'true' shape in the new coordinate system. A straight line in one coordinate system is not necessarily a straight line in a different coordinate system. Set the bAngularDensify parameter if you want to densify the geometries while they are projected.
//This example demonstrates how to use IGeometry2::ProjectEx
public void ProjectExExample()
{
//Create source spatial reference
ISpatialReferenceFactory spatialReferenceFactory = new SpatialReferenceEnvironmentClass();
ISpatialReference spatialReference = spatialReferenceFactory.CreateGeographicCoordinateSystem((int)esriSRGeoCSType.esriSRGeoCS_WGS1984);
spatialReference.SetFalseOriginAndUnits(-80.0000000232831, 39.9999999767169, 42949672.9);
//Create envelope and define its spatial reference
IEnvelope envelope = new EnvelopeClass();
envelope.PutCoords(-68.6076204314651, 49.6186709634653, -68.5531907607304, 49.6530789785679);
envelope.SpatialReference = spatialReference;
//Destination spatial reference
IProjectedCoordinateSystem projectedCoordinateSystem = spatialReferenceFactory.CreateProjectedCoordinateSystem((int)esriSRProjCSType.esriSRProjCS_NAD1927UTM_19N);
//Define the XYDomain equivalent to SetFalseOriginAndUnits
projectedCoordinateSystem.SetDomain(500000, 600000, 5300000, 5600000);
//Create a Geotransformation (Datum transformation)
IGeoTransformation geoTransformation = spatialReferenceFactory.CreateGeoTransformation((int)esriSRGeoTransformationType.esriSRGeoTransformation_NAD1927_To_WGS1984_12) as IGeoTransformation;
String report = "Print envelope coordinates before projection:\n" +
envelope.XMin + " , " + envelope.YMin + " , " + envelope.XMax + " , " + envelope.YMax + "\n\n\n";
//Project envelope
IGeometry2 geometry = envelope as IGeometry2;
geometry.ProjectEx(projectedCoordinateSystem as ISpatialReference, esriTransformDirection.esriTransformReverse, geoTransformation, false, 0, 0);
report = report + "Print envelope coordinates after projection:\n" +
envelope.XMin + " , " + envelope.YMin + " , " + envelope.XMax + " , " + envelope.YMax;
System.Windows.Forms.MessageBox.Show(report);
}