It seems that in the 4.17 version of the Unreal Engine an already fixed bug got back, it’s related to the morph target system.
I had the exact same issue in the 4.9.1 version of the engine.
In short the bug does this:
My car mesh flickers when it’s moving, it looks like it’s jumping between the original undamaged state and the damaged state, using morph targets for damage control in my Advanced Vehicle Kit.
Back then, the issue had the UE-21684 ticket number.
Here is the link to the older answers hub post, which describes most of the bug:
If any more information is needed, i’m willing to help.
I took a look at your old post, and your old example files are no longer there. I am going to need some more information, so if you could post some screenshots(a sample project or gif etc.) from the new project, I will take another look into this issue. If you have the old files in which you had this problem in, or any screenshots etc., feel free to post those as well. Those can give me a benchmark idea as to what I am looking for to compare the results etc.
I have made a build from my project in 4.17 where you can clearly see the issue.
The issue only appears when the car is damaged and it’s moving.
It’s not a LOD issue, i have changed the LOD’s draw sizes but it didn’t do anything, so i guess it’s again something wrong with the morph targets.
I’ve taken a look at the packaged build you sent me and I am seeing the issue you are referring to. However, there could be several different factors causing it, and am unable to repro it. I will need some more info. Does this happen in the editor as well or is just occurring when it is packaged out? It looks like you have some PhysX files in the folder, this could be something that contributing to the issue as well. Also, did you use Maya or 3ds Max for making your morph targets? If you send me the FBX or the UE4 project with just car set up, I can take better a look at how you have everything implemented. This way I can tell if there is a setting somewhere that is causing it or if it is a bug.
Yes, it’s occurring in the editor and in the package/build too.
I don’t use any Autodesk related software, the morph targets for the car was made in Blender 3D.
I’m willing to send you the project files but, where/how should i upload it, or just send it through a private message?
You can either put it in Google Drive and post the link here(there is an option for only moderators to be able to see it), but there is a file size limit and it’s pretty small(5 MB). I’m not sure the size of your files or how public you want them. If you would prefer, you can pm me here. Although if you send them this way, let me know on this thread so I will be sure to see it.
I’ve taken a look at the project and I am having a hard time reliably reproducing the issue. There are a lot of different variables that may be causing it. Have you tried this in a clean project? I’m unable to tell if it is the engine or something within it. Would it be possible for you to send me a simplified version with only the assets needed to reproduce the issue along with the steps that you are taking to reproduce this?
I have gone ahead and logged it as a bug. If you would like to keep an eye on it, you can do so here in the public tracker. If you have any other questions regarding the issue feel free to reopen this thread.