This is in regard to a widely reported bug of blueprint resetting itself to parent BP’s value. I’m creating a new thread because I’ve managed to identify the key factor that causes it and have included the project files.
Causes:
Blueprint value is derived from parent blueprint. Child class’ own variable do not reset
It will happen ONLY if auto-recompile runs in PIE . If this does not happen it will not reset.
Manually recompilation of blueprint does not causes the reset.
Reset happen on engine restart regardless of whether map is saved or not.
Run project. Click on the actor ( the one with billboard )
Change value on the sections as shown in the attached picture.
Save map. Save All.
Run PIE. Let it recompile. Ignore Errors.
After PIE. Resave map; Verify the changed values.
Close editor and restart project. Values will be resetted.
Things to note :
If you restart editor at step 3 , without step 4 and 5. There is no reset. I tried re-creating in a blank project but I’m unable to simulate a situation where blueprint recompile during PIE. In my new project PIE doesn’t force recompile anything. It seems to show that No Blueprint need recompiling. Hence I cannot verify this in a clean project.
I really hope this help to solve this bug that has been there for such a long time
I would like to thank you for the additional information. As you have mentioned, this issue that has already been reported. I will be happy to update the report with the new information. However, I will need to request that you not create additional threads on this issue and instead update the ones that have already been created (this helps us with tracking). Additional threads make the tracking of this issue more complex. I will be pasting a link back to your original thread in this reply. Please post all future updates there.
I have the same issue on 4.11.2 but can’t even really replicate it myself because it happens from time to time … i have a master bp of a door and a lot of its variations as blueprints with class set to the master bp … the settings that I’ve defined in these bps based on the master stay unchanged but everything set on level gets reset to its default values … I even can edit the master bp without reseting the values on derived bps but sometimes they reset without anything being changed … this is very frustrating as at this moment we have to reconfigure all changed elements by hand and can’t be sure it won’t reset again tommorow … or in an hour from now
Still in in 4.14.2. I met a time traveler who claimed to have a build of 4.68, and he confirmed it is still an issue in that version, but they have direct-neutral-interfacing VR support so that’s something
There is a lot of confusion surrounding this thread do to the way it appears to link back to other threads. However, I believe that you are correct in that the issue I link before was not the right one. I would like to clear things up. So will be happy to investigate the issue again to insure that there is a solid answer.
I have a few questions for you that will help narrow down what issue it is exactly that you are experiencing.
Quick questions:
Can you reproduce this issue in a clean project?
If so, could you provide a detailed list of steps to reproduce this issue on our end.
Could you provide screen shots of any blueprints/settings that may be involved.
We have not heard back from you in a few days, so we are marking this post as Resolved for tracking purposes. If you are still experiencing the issue you reported, please respond to this message with additional information and we will follow up.
Rudy, this is most certainly not resolved. As many others have mentioned in numerous related threads, this issue is an EXTREME problem. Just because JoeWinter-whoever didn’t respond to you doesn’t mean the countless other posts are without merit. This issue is reproducible with a little bit of effort on your part. Please, re-open it, create a new Issues post, and get to the bottom of it. It is causing serious problems in a project that has a lot of time and money invested in it. Thank you.
I forgot to reply and frankly didn’t prioritise it because I’ve given up hope on the Answerhub at this point and feel like I get more mileage out of atting Epic employees on Twitter.
It’s absurd that with the number of people having this problem, the years it’s been going on for, and the number of repro cases provided in the various threads, that they aren’t able to reproduce. I’ve actually decided to stop recommending UE4 to people until this is resolved. We’re in a thread with a repro case right now that nobody even seems to be attempting to follow the steps for.
I have ran several tests to try and reproduce this issue on our end however, I have been unable to do so. The reproduction steps provided on this thread do not reproduce the issue for me and the original project that was provided on this thread is no longer available. I will need further information in order to reproduce this issue. Could you provide answers to the questions that were asked of ? As stated before I will be happy to look into the issue further, however more information is needed.
In response to your previous post about this issue being closed after so many days. This was done for tracking purposes and it allows other users to see at a glance that it has not been fully resolved in case they have more information that they would like to share. It also helps us keep track of when a thread is updated so that we can respond (example in the case of someone providing more information). I hope that this information helps.
Questions restated:
Can you reproduce this issue in a clean project?
If so, could you provide a detailed list of steps to reproduce this issue on our end?
Could you provide screen shots of any blueprints/settings that may be involved?
The problem with repro for this specific issue is that it would take even more of my precious time. The issue is sporadic, and as far as I can tell there is no specific trigger for it. I’ll go two weeks at a time without any issue, then suddenly all of the child actors of a parent will have certain of its variables reset. I then have to spend hours debugging, because it’s not immediately obvious to me that that’s what caused the issue.
It seems to be some sort of architectural issue, and I’m sure an expert programmer could spot it eventually.
I won’t repro it, for the reasons stated above, but if you’d like to try a bit harder, below are some recommendations to generate the issue:
Create a blueprint actor with numerous variables (try all types… vectors, enums, booleans, etc.). Create numerous child actors from the parent and place them around a level, and set each of them to have different values from the parent. From here, experiment with then making code changes to the parent and saving them, or making changes to the level, or even creating a c++ class and having the parent inherit from that. I would also try forcing a crash of the editor, as that seems to have some relevance.
I should also add that the problem becomes more consistent when editable variables on a blueprint actor in a level reference another blueprint actor in the level. I’m thinking this might have something to do with the order of objects being instantiated on level load? If actor 1 references actor 2, and actor 2 references actor 1, it is usually a matter of time before one of those references changes back to None.
