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PlaneFinding.DLL from GitHub doesn't load


I am experiencing wired issue when trying to use HoloToolkit's spatial mapping from latest GitHub version. It throws DLLNotFound exception from PlaneFinding.FindSubPlanes() at DLLImports.FindSubPlanes(...). Checked that the DLL is present in the solution and even shows up in debug output as loaded plugin when app is debugged, but still throws the exception.
I tried to use older/simpler/stripped down version of HoloToolkit from HoloAcademy in the same solution instead of latest from the GitHub - works without any issues.

Is it a known issue? Am I missing something?


Best Answers


  • When you added the PlaneFinding dll's to your project, did you include the matching meta files?

    These DLL's must be explicitly set for their platform and CPU.

    Click on the DLL in your project and see if it has these settings:

    Note: the Path might be different, but it must be under a Plugins directory.

  • Mine are the same:

    Still, when running the app getting the following output:

    Loading native plugins

    Loading PlaneFinding.dll

    Loading SharingClient.dll

    Module information:
    Built with Compiler Ver '190023026'
    Built from '5.4/platform/winrt/hololens' branch
    Version is '5.4.0b10-HTP (24077ef8c12f)'
    Release build
    Application type 'D3D11'
    Used 'UWP'

    PlayerConnection initialized from C:/Data/Users/DefaultAccount/AppData/Local/DevelopmentFiles/zzzVS.Release_x86.alexg/Data (debug = 0)

    PlayerConnection initialized network socket : 55046

    Multi-casting "[IP] [Port] 55046 [Flags] 2 [Guid] 1472931004 [EditorId] 4294967295 [Version] 1048832 [Id] MetroPlayerX86(HoloLens-O9IFG) [Debug] 0" to []...

    GfxDevice: creating device client; threaded=1


    Version:  Direct3D 11.0 [level 11.0]
    Renderer: Microsoft RemoteFX Graphics Device - WDDM (ID=0x2c1)
    Vendor:   Microsoft
    VRAM:     639 MB

    Initialize engine version: 5.4.0b10-HTP (24077ef8c12f)

    Logical Screen DPI is 144.00.

    Resolution: Switching to 1268 x 720 Fullscreen: True

    Resolution: ApplicationView::IsFullScreenMode = False

    Resolution: Entering fullscreen mode...

    Resolution: Resizing swapchain to 1268 x 720 Fullscreen: True

    Resolution: Done.

    UnloadTime: 1.894500 ms

    Starting the observer.

    (Filename: C:\buildslave\unity\build\artifacts/generated/Metro/runtime/UnityEngineDebugBindings.gen.cpp Line: 45)

    Setting up 1 worker threads for Enlighten.

    Thread -> id: 17d8 -> priority: 1

    Stopping the observer.

    (Filename: C:\buildslave\unity\build\artifacts/generated/Metro/runtime/UnityEngineDebugBindings.gen.cpp Line: 45)

    1 SpatialMappingManager.Instance.DrawVisualMeshes = False

    (Filename: C:\buildslave\unity\build\artifacts/generated/Metro/runtime/UnityEngineDebugBindings.gen.cpp Line: 45)

    Exception thrown: 'System.DllNotFoundException' in Assembly-CSharp.dll
    Exception thrown: 'System.AggregateException' in mscorlib.ni.dll
    AggregateException: One or more errors occurred.
    at System.Threading.Tasks.Task1.GetResultCore(Boolean waitCompletionNotification) at System.Threading.Tasks.Task1.get_Result()
    at HoloToolkit.Unity.SurfaceMeshesToPlanes.d__24.MoveNext()
    at UnityEngine.Internal.$MethodUtility.$Invoke969(Int64 instance, Int64* args)
    at UnityEngine.Internal.$MethodUtility.InvokeMethod(Int64 instance, Int64* args, IntPtr method)
    (Filename: Line: 0)

    The one that works (from older version of HoloTolkit) has slightly different settings:


  • @Jackson said:
    We are investigating this. For now, please use the PlaneFinding DLL from the SpatialMapping course that is working for you.

    Yes, that's what I am doing. Thanks.

  • Great, thanks for the info!

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