InterVisibility not detecting obstruction

[RotateAt60MPH]

Describe the bug
No terrain obstacles detected when there should be.

To Reproduce
Steps to reproduce the behavior:

1. Execute the following unit test:

  [Fact]
  public void IntervisibilityTest()
  {
    var boundingBox = new BoundingBox( -114.81670660619355, -114.79753117282172, 50.88760538298977, 50.8997005129077 );
    var dataSet = DEMDataSet.RegisteredNonLocalDatasets.First( x => x.Name == "AW3D30" );
    _demNetElevationService.DownloadMissingFiles( dataSet, boundingBox );

    var start = new GeoPoint
    {
      Elevation = 1876.8404541015625,
      Latitude = 50.89365334058617,
      Longitude = -114.80711764454496
    };

    var end = new GeoPoint
    {
      Elevation = 2111.0537109375,
      Latitude = 50.885127771762058,
      Longitude = -114.80711764454496,
      DistanceFromOriginMeters = 949.06197559241423
    };

    var result = _demNetElevationService.GetIntervisibilityReport( new List<GeoPoint> { start, end }, 0, 0 );

  }

Expected behavior
There should be an obstacle detected on the mountain ridge.

Screenshots

Desktop (please complete the following information):

• OS: Windows 11, .Net C# 8

[RotateAt60MPH]

This appears to be DataSet specific. Switching to SRTM_GL3 works, so there's something odd about AW3D30. Are insights into why?

[xfischer]

Hi @RotateAt60MPH, I'm looking at it

[xfischer]

It's a bug, here's an STL model at the same location. Will run the code and let you know.

[RotateAt60MPH]

Thanks Xavier.
Corey.

[xfischer]

I've found the issue : referencing of AW3D30 has changed, leading to compute errors on this case (a strict north/south line)

[xfischer]

@RotateAt60MPH package 8.0.1 published with fix. Can you test ?

[xfischer]

Hi Corey, Did the fix worked for you ? Cheers Xavier

…

________________________________ De : Corey Wirun ***@***.***> Envoyé : dimanche 18 mai 2025 21:52 À : dem-net/DEM.Net ***@***.***> Cc : Xavier Fischer ***@***.***>; Comment ***@***.***> Objet : Re: [dem-net/DEM.Net] InterVisibility not detecting obstruction (Issue #122) [https://avatars.githubusercontent.com/u/8569712?s=20&v=4]RotateAt60MPH left a comment (dem-net/DEM.Net#122)<#122 (comment)> Thanks Xavier. Corey. — Reply to this email directly, view it on GitHub<#122 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AAVF6QVDCXQCADV7ERBJJIT27DQILAVCNFSM6AAAAAB5DTJ736VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQOBZGE3TOOBYGY>. You are receiving this because you commented.Message ID: ***@***.***>

[RotateAt60MPH]

Fixed in 8.0.1! Merci bien, Xavier!