I’m following the CitySample example of using the new MassEntity system to create a Mass StateTree with some states and tasks. When I run my level, shortly after I hit this assertion:
Assertion failed: (ChunkIterator->SubchunkStart + ChunkLength) <= Chunk.GetNumInstances() && ChunkLength > 0 [File:D:\UE5\UnrealEngine\Engine\Plugins\Runtime\MassEntity\Source\MassEntity\Private\MassArchetypeData.cpp] [Line: 389]
Invalid subchunk, it is going over the number of instances in the chunk or it is empty.
Has anyone run into this? Any idea what’s going on?
I think I figured this out. In one of my StateTree Task classes (FMassStateTreeTaskBase subclass), in the EnterState method I was calling EntitySubsystem.AddTagToEntity(). I think this was causing the chunk to get modified while it was being iterated over which is bad. To resolve, I had to call EntitySubsystem.Defer().AddTag().
Great find. Likewise, I’ll get an editor crash if I am trying to do EntitySubsystem.Defer().{add/remove/tag/fragment} during ExitState. Have you experienced this? Cheers.
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