/// <summary>
/// Gets the points on the geometry where the first and last M value occurs.
/// </summary>
/// <param name="source">The geometry.</param>
/// <returns>Returns a <see cref="IEnumerable{T}" /> representing the points of M values.</returns>
public static IEnumerable <IPoint> GetPointsAtMs(this IMSegmentation3 source)
{
double firstM, lastM;
source.QueryFirstLastM(out firstM, out lastM);
var collection = source.GetPointsAtM(firstM, 0);
if (collection.GeometryCount == 1)
{
yield return((IPoint)collection.Geometry[0]);
}
collection = source.GetPointsAtM(lastM, 0);
if (collection.GeometryCount == 1)
{
yield return((IPoint)collection.Geometry[0]);
}
}
/// <summary>
/// object polyline. Distance negative -> upstream
/// </summary>
/// <param name="geometricNetwork">object geometricNetwork</param>
/// <param name="resultEdges">objects resultEdges</param>
/// <param name="distance">value of distance</param>
/// <param name="point">object point</param>
/// <param name="offset">offset of polyline</param>
/// <param name="messageInfo">info on result</param>
/// <returns>object IGeometry (polyline or point)</returns>
internal static IGeometry GetPolylinePosAlong(ESRI.ArcGIS.Geodatabase.IGeometricNetwork geometricNetwork, IEnumNetEID resultEdges, double distance, IPoint point, double?offset, ref string messageInfo)
{
IGeometry geometryBag = new GeometryBagClass();
geometryBag.SpatialReference = point.SpatialReference;
IGeometryCollection geometryCollection = geometryBag as IGeometryCollection;
IEIDHelper eidHelper = new EIDHelperClass();
eidHelper.GeometricNetwork = geometricNetwork;
eidHelper.ReturnGeometries = true;
eidHelper.ReturnFeatures = false;
IEnumEIDInfo enumEIDinfo = eidHelper.CreateEnumEIDInfo(resultEdges);
enumEIDinfo.Reset();
IEIDInfo eidInfo = enumEIDinfo.Next();
while (eidInfo != null)
{
IGeometry geometry = eidInfo.Geometry;
geometryCollection.AddGeometry(geometry);
eidInfo = enumEIDinfo.Next();
}
ITopologicalOperator unionedPolyline = new PolylineClass();
unionedPolyline.ConstructUnion(geometryBag as IEnumGeometry);
IPolyline pl = unionedPolyline as IPolyline;
if (distance < 0)
{
pl.ReverseOrientation();
distance = Math.Abs(distance);
}
IMAware mAware = pl as IMAware;
mAware.MAware = true;
IMSegmentation3 mSegmentation = unionedPolyline as IMSegmentation3;
mSegmentation.SetMsAsDistance(false);
IPoint ptTmp = new PointClass();
double distanceAlong = 0;
double distanceFromCurve = 0;
bool rightSide = false;
pl.QueryPointAndDistance(esriSegmentExtension.esriNoExtension, point, false, ptTmp, ref distanceAlong, ref distanceFromCurve, ref rightSide);
object mStartArray = mSegmentation.GetMsAtDistance(distanceAlong, false);
double[] mStart = mStartArray as double[];
double distanceDownStream = distanceAlong + distance;
IPolyline resultPolyline = mSegmentation.GetSubcurveBetweenMs(mStart[0], distanceDownStream) as IPolyline;
if (resultPolyline.IsEmpty)
{
return(point);
}
if (mSegmentation.MMax < distanceDownStream)
{
messageInfo = "The set distance exceeds the length of network";
}
return(Helper.ConstructOffset(resultPolyline, offset));
}
