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WmtsAsyncLayer stops drawing when zooming in to lower scales

#1

Upgrading WmtsLayer from TG 10 to TG 14. In testing with our Planet data I noticed that it stops drawing when zoomed in too far. Further testing reveals this also happens with other Wmts layers. Usually this happens when the scale is 1:4514 or smaller. The exception is sometimes The HTTP request failed with status code: BadRequest and sometimes Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index.

I have attached a sample project.

Thanks!

Steve

WmtsZoomInProblem.zip (96.5 KB)

#2

Hi Steve,

We recreated the issue, and we found it’s the server starting to return “BadRequest” since zoom17, here is the uri for example:
https://basemap.nationalmap.gov/arcgis/rest/services/USGSTopo/MapServer/WMTS?service=WMTS&request=GetTile&version=1.0.0&layer=USGSTopo&style=default&format=image/png&TileMatrixSet=GoogleMapsCompatible&TileMatrix=17&TileRow=52892&TileCol=30292

even this request is valid according to its Capabilities
basemap.nationalmap.gov/arcgis/rest/services/USGSTopo/MapServer/WMTS?service=WMTS&request=GetCapabilites

I tried RESTFul service and it returns the same result.
https://basemap.nationalmap.gov/arcgis/rest/services/USGSTopo/MapServer/WMTS/tile/1.0.0/USGSTopo/default/GoogleMapsCompatible/17/52892/30292

It returns correctly for zoom16 and above.

We didn’t recreate the “Index was out of range/non-negative and less than the size of the collection” issue, does this happen randomly or it happens when zooming into some specific area?

Thanks,
Ben

#3

Hi Ben,

Looks like the problem with the USGSTopo service may be on the server itself. I looked into it a bit more and it looks like the ‘Index out of range’ error is only happening when we access Planet data. I am unable to send a sample project because of the key needed to access the data, but I do have the error and the request Uri for the error:

System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index
   at ThinkGeo.Core.RasterXyzTileAsyncLayer.<DrawWithoutProjectionConverterAsync>d__48.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at ThinkGeo.Core.RasterXyzTileAsyncLayer.<DrawAsyncCore>d__44.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at ThinkGeo.Core.AsyncLayer.<DrawTranslationAsync>d__7.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at ThinkGeo.Core.AsyncLayer.<DrawAsync>d__6.MoveNext()
RequestUri: https://tiles.planet.com/basemaps/v1/latest-series/473b9b21-5940-45c8-9729-c765619eda4d/gmap/13/1981/3359.png?api_key=&proc=rgb

Anything helpful here?

Thanks!

Steve

#4

Hi Steve,

Please update to the latest beta051 and try again. In this build, the layer should throw a more descriptive exception with a detailed stack trace.

Also, please enable internal logging so we can see whether any internal errors are reported:

ThinkGeoDebugger.LogType  = ThinkGeoLogType.All;
ThinkGeoDebugger.LogLevel = ThinkGeoLogLevel.Error;

Thanks,
Ben

#5

Hi Ben,

Here is the new exception stack trace:

System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index
   at System.ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource)
   at System.Collections.Generic.List`1.get_Item(Int32 index)
   at ThinkGeo.Core.WmtsAsyncLayer.GetRequestUri(Int64 x, Int64 y, Int32 zoomLevel)
   at ThinkGeo.Core.WmtsAsyncLayer.GetImageUriAsyncCore(Int32 zoomLevel, Int64 x, Int64 y, Single resolutionFactor)
   at ThinkGeo.Core.WebRasterXyzTileAsyncLayer.<GetImageUriAsync>d__33.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at ThinkGeo.Core.WebRasterXyzTileAsyncLayer.<GetTileAsyncCore>d__35.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at ThinkGeo.Core.RasterXyzTileAsyncLayer.<GetTileAsync>d__66.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at ThinkGeo.Core.RasterXyzTileAsyncLayer.<GetCloudRasterTileInfoAsync>d__65.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at ThinkGeo.Core.RasterXyzTileAsyncLayer.<DrawWithoutProjectionConverterAsync>d__56.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at ThinkGeo.Core.RasterXyzTileAsyncLayer.<DrawWithoutProjectionConverterAsync>d__56.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at ThinkGeo.Core.RasterXyzTileAsyncLayer.<DrawAsyncCore>d__52.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at ThinkGeo.Core.AsyncLayer.<DrawTranslationAsync>d__7.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at ThinkGeo.Core.AsyncLayer.<DrawAsync>d__6.MoveNext()

If necessary I can get you a temporary key to access the Planet data. Let me know how I can get it to you.

Thanks!

Steve

#6

That will be great! Can you send it to support@thinkgeo.com?

#7

Hi Ben,

I have sent the key.

Steve

#8

As promised, here is a sample project. You will need to place the key in the code where indicated, in class CustomWmtsLayer.

Thanks!

Steve

Planet_Test.zip (129.8 KB)

#9

Hi Steve,

Thanks for the sample and the key, it’s really helpful!

It seems the TileMatrixSet (GoogleMapsCompatible15) on the server supports zoom 0 ~ 15, so if on the client we zoom in beyond zoom15, that “Index was out of range” exception will be thrown.

We’ve fixed it in the latest beta (v14.5.0-beta055)

  1. Nothing will be displayed (and no exception will be thrown) if zooming into a zoom with no data available on the server.
  2. Write this code
wmtsLayer.RenderBeyondMaxZoom = True

and it will try to fetch the data from the last available zoom. For example rendering Zoom16 from the data of Zoom15

Have a try and let me know what you think.

Thanks,
Ben

#10

Thanks for the fix, works fine now! Do you know when this change will be in a production release?

Steve

#11

It will be v14.5 in May, 2026.

If you don’t want to use beta, can you try the following with your current production release?

wmtsLayer.RenderBeyondMaxZoom = True

// set the MaxZoomOfTheData
var matrixes = wmtsLayer.GetTileMatrixSets();
var maxZoom = matrixes[wmtsLayer.TileMatrixSetName].TileMatrices.Count - 1;
wmtsLayer.MaxZoomOfTheData = maxZoom;

// or just hard code it
// wmtsLayer.MaxZoomOfTheData = 15;