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IMcPointsFeaturePointAtDistanceFromStart Method

Finds the point on a feature line or boundary that is a given distance from the starting point on that feature.

Namespace:  MediaCy.IQL.Features
Assembly:  MediaCy.IQL.Features (in MediaCy.IQL.Features.dll) Version: 10.0.6912.0
Syntax
VB
Copy
Function FeaturePointAtDistanceFromStart ( 
	Distance As Double,
	FeatureIndex As Integer,
	<OutAttribute> ByRef AtDistanceX As Single,
	<OutAttribute> ByRef AtDistanceY As Single,
	<OutAttribute> ByRef AtDistVertexIndex As Integer,
	Optional CalibratedDistance As Boolean = true
) As Boolean

Parameters

Distance
Type: SystemDouble
The distance from the start of the feature for which the point is sought.
FeatureIndex
Type: SystemInt32
Which feature the point is to be computed for (zero by default).
AtDistanceX
Type: SystemSingle
Returned feature X coordinate at the given distance. Or the last vertex X of the feature if the given Distance is beyond the end (in this case the FeaturePointAtDistanceFromStart will return False).
AtDistanceY
Type: SystemSingle
Returned feature Y coordinate at the given distance. Or the last vertex Y of the feature if the given Distance is beyond the end (in this case the FeaturePointAtDistanceFromStart will return False).
AtDistVertexIndex
Type: SystemInt32
Returned index of the vertex at or beyond which the AtDistanceX/Y point was found. Note that for McRegions this may be the last vertex of the boundary, in which case the returned AtDistanceX/Y point will fall on the closing line segment joining the last boundary vertex to the first. Use the GetFeaturePoints method to retrieve the points associated with all vertices for a feature.
CalibratedDistance (Optional)
Type: SystemBoolean
If True (the default) and the SpatialCalibration property is not Nothing, then the supplied distance must be in calibrated units. If False, then the supplied distance is in pixel units. Note that the AtDistanceX and AtDistanceY results are always given in pixel coordinates, irrespective of the state of this argument.

Return Value

Type: Boolean
True if the given Distance from the start of the feature falls somewhere on the feature line or boundary. False is returned if the given Distance is beyond the end of the feature (for McPoints, False is always returned for any non-zero Distance, though using this method for a McPoints makes little sense).

Implements

IMcFeaturesFeaturePointAtDistanceFromStart(Double, Int32, Single, Single, Int32, Boolean)
Remarks
Given a distance, this method computes the point at that distance from the start of a given McLines feature line or the start of a given McRegions feature boundary. In addition, the index of the vertex of the segment on which the distance lies is returned. Should the given distance be beyond the end of the line or longer than the region boundary, then False is returned from this method. The FeaturePointAtDistanceFromStart method can be useful for computing an edge point from the McProfileEdges.EdgeDistances property (though those points are also directly available via the McProfileEdges.EdgesAsMcPoints property The reciprocal computation (that is given a vertex and a point, compute the distance along a line or boundary) is done by the DistanceToFeaturePoint method. See PointClosestToPoint for an example using FeaturePointAtDistanceFromStart.
See Also