I have been using hdas in unreal engine a lot lately. I spend a lot of time restarting unreal engine because of crashes.
They may be my fault (bad stuff in the hda file), but most of the time I have no idea what I did to cause the problem or if it is even me.

The latest one is I added a new dropdown item that adds additional geometry but when I try to select it I get hard crash. Every time. A lot of the times when I get crash from reloading changed hda the next time I start unreal it works good with no crashes. Not this time. Crashes every time.

Here is what is in the crash log. I have seen this quite a bit, and I pretty sure I may be doing something bad in my hda, I am just looking for clues to help me track it down.

It would be nice if these hard crashes were caught and a warning shown instead of hard crash.

Anyway here is the error in my crash log. I see all the unknown function calls but I have added no nodes that I have not used a ton in my hdas, so not sure what that is related to.

thanks.

EDIT -> I found the issue although I do not know why. I add new geo with collision geo. The collision geo was a simple box and I had add vertex normals checked. If I uncheck this it works in unreal. The strange things is I have other parts in the hda that also have collision boxes from a box that has add vertex normals checked. So not sure what the deal is. If you need a copy of the hda to debug let me know.

Fatal error:
Rendering thread exception:
Assertion failed: Mesh.VertexFactory->IsInitialized()



0x0000000058BC3FB8 KERNELBASE.dll!UnknownFunction
0x000000001E6476D4 UE4Editor-ApplicationCore.dll!UnknownFunction
0x00000000F441330B UE4Editor-Core.dll!UnknownFunction
0x00000000F43A47F9 UE4Editor-Core.dll!UnknownFunction
0x00000000E99A0D4A UE4Editor-Renderer.dll!UnknownFunction
0x00000000F28EB81A UE4Editor-Engine.dll!UnknownFunction
0x00000000E99756D0 UE4Editor-Renderer.dll!UnknownFunction
0x00000000E9975BF2 UE4Editor-Renderer.dll!UnknownFunction
0x00000000E9974BF8 UE4Editor-Renderer.dll!UnknownFunction
0x00000000E996C2D1 UE4Editor-Renderer.dll!UnknownFunction
0x00000000E99A49C6 UE4Editor-Renderer.dll!UnknownFunction
0x00000000F4274845 UE4Editor-Core.dll!UnknownFunction
0x00000000F4274E2A UE4Editor-Core.dll!UnknownFunction
0x000000001E6F22C4 UE4Editor-RenderCore.dll!UnknownFunction
0x000000001E6F32F6 UE4Editor-RenderCore.dll!UnknownFunction
0x00000000F461092C UE4Editor-Core.dll!UnknownFunction
0x00000000F4602563 UE4Editor-Core.dll!UnknownFunction
0x0000000059841FE4 KERNEL32.DLL!UnknownFunction
0x000000005C3CEFB1 ntdll.dll!UnknownFunction
0x000000005C3CEFB1 ntdll.dll!UnknownFunction

Hi,

We generally try to identify/prevent crashes in the plug-in code, logging warning/errors instead of doing something incorrect, but unfortunately, they can still sometimes happen, as something perfectly valid for Houdini might not be valid for Unreal.

I did find and fixed a potential crash today due to having invalid geometry in a collider group.
That might be the one you were experiencing, but on my side, the add vertex normals weren't what caused it.

Can you please send me your hda so I can double check this.

dpernuit
Hi,

We generally try to identify/prevent crashes in the plug-in code, logging warning/errors instead of doing something incorrect, but unfortunately, they can still sometimes happen, as something perfectly valid for Houdini might not be valid for Unreal.

I did find and fixed a potential crash today due to having invalid geometry in a collider group.
That might be the one you were experiencing, but on my side, the add vertex normals weren't what caused it.

Can you please send me your hda so I can double check this.

I will put together a test file when I get a chance that has no children hdas.

Aladin Sane

dpernuit
Hi,

We generally try to identify/prevent crashes in the plug-in code, logging warning/errors instead of doing something incorrect, but unfortunately, they can still sometimes happen, as something perfectly valid for Houdini might not be valid for Unreal.

I did find and fixed a potential crash today due to having invalid geometry in a collider group.
That might be the one you were experiencing, but on my side, the add vertex normals weren't what caused it.

Can you please send me your hda so I can double check this.

I will put together a test file when I get a chance that has no children hdas.

ok I have some test files - The issue is the collison. It works when you load. And sometimes I can get it to change once but then everytime I change the height parameter it crashes. I have tried many different techniques to get this working but i am at a loss at what else to try.

thanks.