Joining geodetically correct polyline segments in VB.NET

98
2
Jump to solution
10-15-2020 01:55 PM
Highlighted
New Contributor III

hello,

I have some VB.NET code which is constructing a line piece by piece from a set of coordinates in a table.  I was creating the separate iLine and then adding those to a Path object.  Once the series of point composing the line is finished then I add that Geometry into a Polyline.  And that works.  It has recently transpired that creating that I want to create the line as geodesics or loxodromes, depending upon the line.  I found the ConstructGeodeticLineFromPoints member of the IConstructGeodetic interface.  But this creates Polylines so the previous code I had with Paths is no longer working.  I am trying to Union my spearate geodetically accurate polyline segments with a TopologicalOperator but that is taking a whole lot longer and runs into problems after a while.  I was trying to look into SegmentCollections and GeometryCollections to mimic what I had been doing previously with iLines and Paths, but it doesn't seem to be working.  Does anybody have any experience with easily joining together polyline elements programatically together?

cheers

shawn

1 Solution

Accepted Solutions
Highlighted
Occasional Contributor II

Hi Shawn,

To summarize your situation, you want to join a polyline created from calling ConstructGeodeticLineFromPoints (polyline_1) with an existing polyline, say polyline_2, right?  If that's the case, you can use ISegmentCollection like this:

Dim pSegColl_2 As ISegmentCollection

Set pSegColl_2 = polyline_2

Dim pSegColl_1 As ISegmentCollection

Set pSegColl_1 = polyline_1

pSegColl_2.AddSegmentCollection pSegColl_1

View solution in original post

2 Replies
Highlighted
Occasional Contributor II

Hi Shawn,

To summarize your situation, you want to join a polyline created from calling ConstructGeodeticLineFromPoints (polyline_1) with an existing polyline, say polyline_2, right?  If that's the case, you can use ISegmentCollection like this:

Dim pSegColl_2 As ISegmentCollection

Set pSegColl_2 = polyline_2

Dim pSegColl_1 As ISegmentCollection

Set pSegColl_1 = polyline_1

pSegColl_2.AddSegmentCollection pSegColl_1

View solution in original post

Highlighted
New Contributor III

hey Weifang

Thanks very much, that worked.  I didn't think to try doing it that way at all.  That's so simple, and so elegant - exactly what I was hoping for.

cheers

shawn

Reply
0 Kudos