SplitAtPoint Method (IGeometryEngine)

In This Topic

Adds a new vertex along the multipoint at the specified input point or the projection onto the multipart of the specified input point.

Syntax

Visual Basic (Declaration)
C#

Function SplitAtPoint( _
   ByVal multipart As Multipart, _
   ByVal splitPoint As MapPoint, _
   ByVal projectOnto As Boolean, _
   ByVal createPart As Boolean, _
   ByRef splitOccurred As Boolean, _
   ByRef partIndex As Integer, _
   ByRef segmentIndex As Integer _
) As Multipart

Multipart SplitAtPoint( 
   Multipart multipart,
   MapPoint splitPoint,
   bool projectOnto,
   bool createPart,
   out bool splitOccurred,
   out int partIndex,
   out int segmentIndex
)

Parameters

multipart: The multipart along which the point will be inserted.
splitPoint: The point to be inserted.
projectOnto: Determines if the output point will be located on the curve. If true and the splitPoint is not already on the curve then the point is projected onto the curve.
createPart: Determines if parts are to be created. MUST be false for polygons. For polylines, if true, the part on which the new split point falls is split into two parts with the newly added vertex serving as the end of the first part and the beginning of the second.
splitOccurred: Determines if a split occurred.
partIndex: Part index that has the point added. If splitOccurred is false, this value should be ignored.
segmentIndex: Segment index that has the point added. The segment may be a newly created segment. If splitOccurred is false, this value should be ignored.

Return Value

A geometry with the new vertex added. If no split occurred, then the original multipart is returned.

Exceptions

Exception	Description
System.ArgumentNullException	Either multipartor splitPointor both are null.
System.ArgumentException	createPart must be false for polygons.
System.InvalidOperationException	Incompatible spatial references between the input geometries.
ArcGIS.Core.Geometry.Exceptions.GeometryObjectException	The input multipart is empty.
ArcGIS.Core.Geometry.Exceptions.InvalidParameterException	The input point is empty, or the specified splitting distance is not included in the curve to be split.

Example

Split multipart at point

{
  // define a polyline
  MapPoint startPointZ = MapPointBuilderEx.CreateMapPoint(1, 1, 5);
  MapPoint endPointZ = MapPointBuilderEx.CreateMapPoint(20, 1, 5);

  Polyline polylineZ = PolylineBuilderEx.CreatePolyline([startPointZ, endPointZ]);

  // define a split point
  MapPoint splitPointAboveLine = MapPointBuilderEx.CreateMapPoint(10, 10, 10);

  // split the polyline at the point. Don't project the split point onto the line, don't create a new part
  var splitPolyline = GeometryEngine.Instance.SplitAtPoint(polylineZ, splitPointAboveLine, false, false, out bool splitOccurred, out int partIndex, out int segmentIndex);

  // splitOccurred = true
  // partIndex = 0
  // segmentIndex = 1
  // splitPolyline.PointCount = 3
  // splitPolyline.PartCount = 1
  // splitPolyline coordinates are (1, 1, 5), (10, 10, 10), (20, 1, 5)

  // split the polyline at the point.  dont project the split point onto the line, do create a new part
  splitPolyline = GeometryEngine.Instance.SplitAtPoint(polylineZ, splitPointAboveLine, false, false, out splitOccurred, out partIndex, out segmentIndex);

  // splitOccurred = true
  // partIndex = 1
  // segmentIndex = 0
  // splitPolyline.PointCount = 4
  // splitPolyline.PartCount = 2
  // splitPolyline first part coordinates are (1, 1, 5), (10, 10, 10)
  // splitPolyline second part coordinates are (10, 10, 10), (20, 1, 5)

  // split the polyline at the point.  do project the split point onto the line, don't create a new part
  splitPolyline = GeometryEngine.Instance.SplitAtPoint(polylineZ, splitPointAboveLine, false, false, out splitOccurred, out partIndex, out segmentIndex);

  // splitOccurred = true
  // partIndex = 0
  // segmentIndex = 1
  // splitPolyline.PointCount = 3
  // splitPolyline.PartCount = 1
  // splitPolyline coordinates are (1, 1, 5), (10, 10, 5), (20, 1, 5)

  // split the polyline at the point.  do project the split point onto the line, do create a new part
  splitPolyline = GeometryEngine.Instance.SplitAtPoint(polylineZ, splitPointAboveLine, false, false, out splitOccurred, out partIndex, out segmentIndex);

  // splitOccurred = true
  // partIndex = 1
  // segmentIndex = 0
  // splitPolyline.PointCount = 4
  // splitPolyline.PartCount = 2
  // splitPolyline first part coordinates are (1, 1, 5), (10, 10, 5)
  // splitPolyline second part coordinates are (10, 10, 5), (20, 1, 5)

  //
  // try to split with a point that won't split the line  - pt extends beyond the line
  //

  var pointAfterLine = MapPointBuilderEx.CreateMapPoint(50, 1, 10);
  splitPolyline = GeometryEngine.Instance.SplitAtPoint(polylineZ, pointAfterLine, false, false, out splitOccurred, out partIndex, out segmentIndex);

  // splitOccurred = false
  // ignore partIndex, sgementIndex
  // splitPolyline is the same as polylineZ

  ///
  ///  multipart polygon
  ///
  List<Coordinate3D> coordsZ =
  [
    new Coordinate3D(10,10,5),
  new Coordinate3D(10,20,5),
  new Coordinate3D(20,20,5),
  new Coordinate3D(20,10,5)
  ];

  List<Coordinate3D> coordsZ_2ndPart =
  [
    new Coordinate3D(30,20,10),
  new Coordinate3D(30,30,10),
  new Coordinate3D(35,28,10),
  new Coordinate3D(40,30,10),
  new Coordinate3D(40,20,10)
  ];

  var builder = new PolygonBuilderEx
  {
    HasZ = true
  };
  builder.AddPart(coordsZ);
  builder.AddPart(coordsZ_2ndPart);

  Polygon multipart = builder.ToGeometry();

  // pointA is closer to the first part of the multipart - the split occurs in the first part
  var pointA = MapPointBuilderEx.CreateMapPoint(22, 18, 7);
  var splitPolygon = GeometryEngine.Instance.SplitAtPoint(multipart, pointA, false, false, out splitOccurred, out partIndex, out segmentIndex);

  // splitPolygon.PointCount = 12
  // splitPolygon.PartCount = 2
  // splitPolygon first part coordinates  (10, 10, 5), (10, 20, 5), (20, 20, 5), (22, 18, 7), (20, 10, 5), (10, 10, 5)

  // pointB is midPoint between the 2 parts - no split will occur
  var pointB = MapPointBuilderEx.CreateMapPoint(25, 20, 7);
  splitPolygon = GeometryEngine.Instance.SplitAtPoint(multipart, pointB, true, false, out splitOccurred, out partIndex, out segmentIndex);

  // splitOccurred = false
  // ignore partIndex, sgementIndex
  // splitPolyline is the same as polylineZ
}

Requirements

Target Platforms: Windows 11 Home, Pro, Enterprise (64 bit)

ArcGIS Pro version: 3.0 or higher.

Reference

IGeometryEngine Interface
IGeometryEngine Members

Send feedback