ArcGIS Pro 3.3 API Reference Guide
ArcGIS.Core.Geometry Namespace / IGeometryEngine Interface / SplitAtPoint Method
The multipart along which the point will be inserted.
The point to be inserted.
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.
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.
Determines if a split occurred.
Part index that has the point added. If splitOccurred is false, this value should be ignored.
Segment index that has the point added. The segment may be a newly created segment. If splitOccurred is false, this value should be ignored.
Example

In This Topic
    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

    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
    ExceptionDescription
    Either multipartor splitPointor both are null.
    createPart must be false for polygons.
    Incompatible spatial references between the input geometries.
    The input multipart is empty.
    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(new List<MapPoint>() { startPointZ, endPointZ });
    
    // define a split point
    MapPoint splitPointAboveLine = MapPointBuilderEx.CreateMapPoint(10, 10, 10);
    
    bool splitOccurred;
    int partIndex;
    int segmentIndex;
    
    // split the polyline at the point.  dont project the split point onto the line, don't create a new part
    var 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, 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 List<Coordinate3D>()
    {
      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 List<Coordinate3D>()
    {
      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();
    builder.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, Windows 10

    ArcGIS Pro version: 3 or higher.
    See Also