Deleting BSP causes crash after PIE

Hi there,

I’ve built a basic scene in Unreal 4.4, and I’ve blocked it out with BSP brushes. Now, having got a mesh alternative, I’m trying to replace the BSP with the static mesh. However, this is proving to be essentially impossible. I can happily delete the BSP objects, but once I do, the editor crashes after I press the PIE button. This isn’t just caused by deleting them, though. Moving them, resizing them, changing some of their settings, etc. All can potentially cause the crash. If I save the map after deleting the BSPs, then the editor will also crash on opening.

When loading the map, I get 3 warnings, dotted about, which are:

LogStats:Warning: MetaData mismatch. Did you assign a stat to two groups? New //STATGROUP_Threads//FMonitoredProcess///Thread_dc4_0///////STATCAT_Advanced//// old //STATGROUP_Threads//FMonitoredProcess///Thread_37ec_0///////STATCAT_Advanced////
LogStats:Warning: MetaData mismatch. Did you assign a stat to two groups? New //STATGROUP_Threads//FMonitoredProcess///Thread_1f08_0///////STATCAT_Advanced//// old //STATGROUP_Threads//FMonitoredProcess///Thread_37ec_0///////STATCAT_Advanced////
LogStats:Warning: MetaData mismatch. Did you assign a stat to two groups? New //STATGROUP_Threads//FMonitoredProcess///Thread_561c_0///////STATCAT_Advanced//// old //STATGROUP_Threads//FMonitoredProcess///Thread_37ec_0///////STATCAT_Advanced////

And my crash log is:


Unknown exception - code 00000001 (first/second chance not available)

Assertion failed: TheModel->Nodes.IsValidIndex( NodeIdx ) [File:D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.4\Engine\Source\Runtime\Engine\Private\ModelRender.cpp] [Line: 99]
Invalid Node Index, Idx:1417, Num:139

KERNELBASE + 23544 bytes
UE4Editor_Core + 3095292 bytes
UE4Editor_Core + 1661738 bytes
UE4Editor_Core + 1541824 bytes
UE4Editor_Engine + 5124051 bytes
UE4Editor_Engine + 5314098 bytes
UE4Editor_CoreUObject + 899050 bytes
UE4Editor_CoreUObject + 1501900 bytes
UE4Editor_CoreUObject + 1498951 bytes
UE4Editor_UnrealEd + 3983183 bytes
UE4Editor_Engine + 3586201 bytes
UE4Editor_UnrealEd + 3975206 bytes
UE4Editor_UnrealEd + 4262521 bytes
UE4Editor_UnrealEd + 4351225 bytes
UE4Editor_UnrealEd + 1812504 bytes
UE4Editor_UnrealEd + 5925286 bytes
UE4Editor!FEngineLoop::Tick() + 3294 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.4\engine\source\runtime\launch\private\launchengineloop.cpp:2098]
UE4Editor!GuardedMain() + 476 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.4\engine\source\runtime\launch\private\launch.cpp:133]
UE4Editor!GuardedMainWrapper() + 26 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.4\engine\source\runtime\launch\private\windows\launchwindows.cpp:125]
UE4Editor!WinMain() + 249 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.4\engine\source\runtime\launch\private\windows\launchwindows.cpp:201]
UE4Editor!__tmainCRTStartup() + 329 bytes [f:\dd\vctools\crt\crtw32\dllstuff\crtexe.c:618]

I can’t recreate this error in a new level, but I would much prefer a solution for restoring this level, or preventing this in the future, as I can’t recreate each level every time this occurs if it’s a common problem. I’m absolutely stuck, and have no idea what to do.

Ah! I fixed it! It seems that deleting all the foliage from the terrain meant I could delete the BSPs no problem. Could anyone enlighten me as to why this would be?

EDIT: It seems that just reducing the foliage cluster size also fixed the error! It got rid of a warning about a large shadow caster. This does seem odd to be related to BSPs, though.

Hey Hoeloe-

I’m trying to recreate the crash you had to investigate how severe the issue is. How much foliage did you have in your level when the crash occurred? If you add the foliage back to the level does the crash reoccur? Any information you can think of would help narrow down the cause and help us look for an answer.

I have a small terrain in the level, which has a couple of thousand instances of grass on it. The issue appears to be that the cluster radius was for some reason set to 10,000, and was casting dynamic shadows. I added the foliage back in and changed the cluster radius, and I could delete the BSPs with no crashes. The BSPs were over the top of the terrain, and a couple of them intersected it, but as far as I can tell, that’s the only place they were related. Despite the fact that the problem no longer occurs, finding the cause would be great. I did find a couple of mentions of this error related to foliage, which is what prompted me to investigate it, this one being most relevant: One BSP brush crashing whole map - World Creation - Epic Developer Community Forums

Could you provide the log files in the folder Saved->Logs from the time of the crash? It would also help to have the your dxdiag which can be found by opening the windows search bar and searching for dxdiag.exe. In the window that appears click “Save All Information” to save a txt file.

Here’s the log:

Here’s the DxDiag:

I will add that the DxDiag logs me using an Intel HD 4000 as my graphics processor, but this is incorrect, as I’m using an Nvidia Geforce 2GB GT 650M. Not the most powerful graphics processor in the world, but more than adequate.

Hey Hoeloe-

Thanks for the information. I have passed this issue on to our developers for further investigation into the cause of this crash as TTP #346051.


Thanks a lot! Hopefully the cause will turn out to be something relatively easy to repair, and in the main time, anyone else having this issue can use the solution I found of lowering the maximum cluster radius.