Unhandled exception

[FransKnibbe]

I am trying to use pg2b3dm (version 2.25.1.0 on Windows) to generate 3D tiles from a table that contains only linestrings. After some time, the following error occurs:

  Start generating tiles...
Creating tile: 7_20_127.glb  Unhandled exception. System.ArgumentNullException: Value cannot be null. (Parameter 'bytes')
   at System.ArgumentNullException.Throw(String paramName)
   at System.IO.File.WriteAllBytes(String path, Byte[] bytes)
   at pg2b3dm.QuadtreeTiler.GenerateTiles(BoundingBox bbox, Tile tile, List`1 tiles, Int32 lod, Boolean createGltf, Boolean keepProjection)
   at pg2b3dm.QuadtreeTiler.GenerateTiles(BoundingBox bbox, Tile tile, List`1 tiles, Int32 lod, Boolean createGltf, Boolean keepProjection)
   at pg2b3dm.QuadtreeTiler.GenerateTiles(BoundingBox bbox, Tile tile, List`1 tiles, Int32 lod, Boolean createGltf, Boolean keepProjection)
   at pg2b3dm.QuadtreeTiler.GenerateTiles(BoundingBox bbox, Tile tile, List`1 tiles, Int32 lod, Boolean createGltf, Boolean keepProjection)
   at pg2b3dm.QuadtreeTiler.GenerateTiles(BoundingBox bbox, Tile tile, List`1 tiles, Int32 lod, Boolean createGltf, Boolean keepProjection)
   at pg2b3dm.QuadtreeTiler.GenerateTiles(BoundingBox bbox, Tile tile, List`1 tiles, Int32 lod, Boolean createGltf, Boolean keepProjection)
   at pg2b3dm.QuadtreeTiler.GenerateTiles(BoundingBox bbox, Tile tile, List`1 tiles, Int32 lod, Boolean createGltf, Boolean keepProjection)
   at pg2b3dm.QuadtreeTiler.GenerateTiles(BoundingBox bbox, Tile tile, List`1 tiles, Int32 lod, Boolean createGltf, Boolean keepProjection)
   at pg2b3dm.Program.QuadtreeTile(String connectionString, InputTable inputTable, StylingSettings stylingSettings, TilesetSettings tilesetSettings, TilingSettings tilingSettings)
   at pg2b3dm.Program.<>c__DisplayClass1_0.<Main>b__0(Options o)
   at CommandLine.ParserResultExtensions.WithParsed[T](ParserResult`1 result, Action`1 action)
   at pg2b3dm.Program.Main(String[] args)

I don't know what the problem can be. I have checked the geometry and radius columns: they do not contain null values.

[bertt]

Hi Frans, from the error it looks like for 1 tile (7_20_127.glb) there is no gltf created. Maybe there are very small lines in the dataset?
Otherwise can you share the input data (in a geopackage or so?) / send it to me?

[FransKnibbe]

Hi Bert! I am not sure if I can share the input data, but I wil try to find out. Meanwhile I can run ST_3DLength() on the data. Coordinate units are metres. What would be a good threshold for finding very small lines?

[bertt]

Maybe there are lines with 2 vertices with startpoint the same as endpoint (just guessing here)... should be easy to find out using a debugger. Or reduce the input dataset so only the problematic geometry remains.

[FransKnibbe]

I was able to generate 3D tiles with a subset of the data. I will do some experiments to try to isolate the problem. I did make sure that all geometries are valid and simple. I will post my findings here.