[Blueprint Help] State tree in HUD crashes when i compare boolean

General Feedback & Requests
1

Hello,

To manage my Ui i added a state tree component in my HUD subclass.

i have some bool in my HUD class, and i compare bool in my "enter Conditions’ for each states in the state tree.

A crash occurs when i recompile my HUD and hit play.

I’ve eliminated all the possibilities, and i isolate the issue :

The Bool compare in enter conditions is the problem.

Does anyone have a clue to help me ?

Thx

2

Ok,

to avoid the crash :

When i make modification in my HUD class i need to recompile the HUD AND the state tree in this strict order.

3

Thanks, it helped me because I was experiencing the same issue with Character AI. Crashes occurred whenever I add anything to the AI character with a linked state tree. So I can confirm that when you change anything that is referencing the state tree you need to hit the compile button in the state tree even if it is compiled.

4

Im so glad i found this post, I was running into the same issue until this solved it. It must be some type of bug where it is looking for older instances of the blueprint data. Hopefully 5.2 fixes this.

The error in particular that I was getting was:
appError called: Assertion failed: FieldSize != 0
in the UnrealType.h file

5

Upon more troubleshooting, it appears to only be happening with bool compares for me.
I took the same task and condition and swapped parameters and it seems to only be having the problem when binding to a boolean value that is inside the linked actor.

I also created a brand new state tree with a root and a single child state using an “On Tick” transition and a Bool Compare as the condition and can replicate the problem

Bool Problem
Bool Problem749×531 26.8 KB

6

For anyone finding this later.

The manual compiling of the StateTree is a workaround for now, I personally ended up using an enum instead of bool’s and avoided the compiling issue until its fixed.

The bug report I submitted for this issue was approved, you can find it here Unreal Engine Issues and Bug Tracker (UE-184193)

Here is a video of the problem and workaround for reference StateTree Bug Report - YouTube

7

It’s still occurring in 5.2
My workaround was to use the evaluator as a mediator for the bool value - then it doesn’t crash

8

I havn’t tested it yet but it seems they marked it as fixed in 5.2.1, might can give it another try to see

9

I’m still having the error in the 5.2.1 version

10

Is the crash logging as a GPU Timeout for you guys?