Bug / Crash ClearTasks / GetPointCloudAnisotropy

[jabza]

Hi,

We've been experiencing a bug with Obi for the past few weeks. It is really hard to reproduce, but sometimes it happens out of the blue. It mostly happens in scenes where we have two solvers. Sometimes at startup, sometimes when we're instantiating a GameObject with an ObiCloth.

The stack trace indicates the issues is with GetPointCloudAnisotropy, but this method is only used in the SoftBody script, which we're not using. I even tried to comment the line in Oni.cs but it is still trying to call it. Here is the stack trace:

0x00007FFE554D0805 (libOni) ClearTasks
0x00007FFE554D6FF5 (libOni) ClearTasks
0x00007FFE55504399 (libOni) GetPointCloudAnisotropy
0x00007FFE5550A28A (libOni) GetPointCloudAnisotropy
0x00007FFE5550A579 (libOni) GetPointCloudAnisotropy
0x00007FFE5552D470 (libOni) GetPointCloudAnisotropy
0x00007FFE876D7E94 (KERNEL32) BaseThreadInitThunk
0x00007FFE887CA251 (ntdll) RtlUserThreadStart

Do you have any indications of what this could be caused by? Our timestep is 0.04 and the max allowed timestep is also 0.04, which works fine for our simulations.

We're running Unity 2019.1.7 and we're using HDRP, but that shouldn't affect Obi(?).

Best, 
Sune

Hey Sune,

I'm seeing this also (2018.4.2f1) - For me this happens when spawning a prefab with a solver via the editor.

========== OUTPUTTING STACK TRACE ==================

0x00007FFCBC9A0033 (libOni) ClearTasks
0x00007FFCBC99DE75 (libOni) ClearTasks
0x00007FFCBC99D611 (libOni) ClearTasks
0x00007FFCBCA04399 (libOni) GetPointCloudAnisotropy
0x00007FFCBCA090C9 (libOni) GetPointCloudAnisotropy
0x00007FFCBCA09EB8 (libOni) GetPointCloudAnisotropy
0x00007FFCBC99BEB5 (libOni) ClearTasks
0x00007FFCBCA02F95 (libOni) GetPointCloudAnisotropy
0x00007FFCBCA080D8 (libOni) GetPointCloudAnisotropy
0x00007FFCBCA0A28A (libOni) GetPointCloudAnisotropy
0x00007FFCBCA0A579 (libOni) GetPointCloudAnisotropy
0x00007FFCBCA2D470 (libOni) GetPointCloudAnisotropy
0x00007FFCF7184034 (KERNEL32) BaseThreadInitThunk
0x00007FFCF84E3691 (ntdll) RtlUserThreadStart

========== END OF STACKTRACE ===========

A crash has been intercepted by the crash handler. For call stack and other details, see the latest crash report generated in:
 * C:/Users/Tom/AppData/Local/Temp/Unity/Editor/Crashes
StackOverflowException: The requested operation caused a stack overflow.
  at (wrapper managed-to-native) Oni.WaitForAllTasks()
  at Obi.ObiArbiter.WaitForAllSolvers () [0x00031] in C:\Users\Tom\Documents\Programming\Unity\Kingfisher\Assets\Externals\Obi\Scripts\Solver\ObiArbiter.cs:41 
  at Obi.ObiSolver.WaitForAllSolvers () [0x0001c] in C:\Users\Tom\Documents\Programming\Unity\Kingfisher\Assets\Externals\Obi\Scripts\Solver\ObiSolver.cs:784 
  at Obi.ObiSolver.SimulateStep (System.Single stepTime) [0x000b1] in C:\Users\Tom\Documents\Programming\Unity\Kingfisher\Assets\Externals\Obi\Scripts\Solver\ObiSolver.cs:672 
  at Obi.ObiSolver.FixedUpdate () [0x00020] in C:\Users\Tom\Documents\Programming\Unity\Kingfisher\Assets\Externals\Obi\Scripts\Solver\ObiSolver.cs:866 
 
(Filename: Assets/Externals/Obi/Scripts/Solver/ObiArbiter.cs Line: 41)

<RI> Initialized touch support.

ObiArbiter appears to be the culprit...