(4.8 Preview 4) - Blocking Volumes Stop Working

It seems that blocking volumes, or any volumes for that matter, stops working if I move them to another map.

For example, I have simplified collisions all over my map, all placed inside the Persistent Map using Blocking Volumes. So I decided to move them over to their respective maps so they can stream in as the new map streams in. After doing this, none of the volumes work anymore when I package the game.

So, just to clarify, the volumes work fine with PIE, but not as a packaged game, or in Stand Alone, or in Launch.

I also tested this with a Navigation Bounds Volume and the same problem happens. I moved it to another map from the persistent map and after doing so, navigation mesh is no longer generated inside that volume when I package the game. Again, the volume work in editor, the nav mesh is there, but packaging the game, that volume no longer works.

As another test I tried moving the volume back to the persistent map, but it is still broken. So once I moved it, that volume is broken, even moving it back does not fix it.

Hi ,

Is this limited to one project or does this occur in a clean project with no additional content?

, thanks for your reply.

Yes, it seems to happen in a clean, new project as well. Here’s how I tested.

  • Create new project, Third Person Blueprint Project.
  • Create an additional map, with something in it. (I copied the box on the floor and added that to the new map)
  • Add the map to stream from the Persistent Level’s level blueprint using the BeginPlay event.
  • Create a new blocking volume inside the Persistent Level. (at this point if you build and then play test with Standalone, the blocking volume works).
  • Move the blocking volume to the secondary map. I select the volume, highlight the map in the Levels browser, then press CTRL M.

So, now if you build and then play test again, using Standalone, the blocking volume no longer works.

I know the level streams in because the box I added into it is there and it’s collision works just fine. It’s just the blocking volume that does not work. I did not test navigation in this test, but with the blocking volume, it’s the same behavior, so I think it’s a valid test with just that.

This morning, just to make sure, I tested the same thing in 4.7.6 and it works fine, so it’s definitely a 4.8 bug.

It also seems that NavModifierVolume does not work at all.

When I place them inside the editor view port, the nav mesh updates correctly, but at run time, the nav mesh does not take those volumes into account. Does not matter which method I use to play test, they never work during actual game play.

So I tested this in both 4.7.6 and 4.8 P4… and in 4.7 it works but in 4.8 it does not.

Hi ,

I was able to reproduce this on my end and have entered a bug report, UE-16750 to be assessed by the development staff. In the meantime, a workaround for this is to create the blocking volume directly in the sublevel. I tested this on my end and blocking volumes initially created in the sublevel work without this error occurring.

, thanks for confirming the bug and your quick response time.

Sure, initial volumes work just fine. I actually went back to 4.7 and saved out a map with all my volumes to load back in 4.8 because all my volumes were broken. So that did fix them again, so I just won’t move them again in 4.8.

Just another quick question. Were you able to confirm the NavModifierVolume problem?. With that one it seems to simply not work, no matter what. The only place it “seems” to work is in editor view port, but during no game play sessions does it ever work.

If you don’t mind can you make a separate post about the NavModifierVolume? The reason we ask for individual posts for different bugs is to keep accurate records. Additionally, if other developers are experiencing the same problem and look for that specific issue, they can comment with their experiences, which may help in locating the cause of the error.

Edit: once the new report is made, please link it here and I’ll make sure I’m assigned to it, in the meantime I’ll try to see what I can find out about the NavModifierVolume.

Thank you, yes, I will make a new post for that, sorry about that.

What I’m gonna do though is download the new release. I saw this morning that 4.8 is now released. So I’m gonna get that first, do some tests and then take it from there, just to make sure the latest build has, or maybe doesn’t have the same problem there.

Cool, thanks again for your efforts on this.

, I wanted to reply here again about the Nav modifiers because they seem ok with the new 4.8 build. I tested with adding a new volume, the same as I tested in P4, and it works now, even in Standalone game. My old volumes I added while in P4 are still broken, but adding new ones do in fact work, so I can replace them.

So, I didn’t want to create a new post for this, just wanted to say that it seems to work now. I will replace all my volumes and see how it goes and if I still have problems with it after that, then I’ll make a new post about.

Cool, thanks.

Ok, so after some more testing I found that this same bug I posted about on here affects the NavModifier as well. (I guess that would be kind of obvious) But I found an extended reason for it get broken, not just moving to a streaming level breaks it, but also moving to a sub folder will break it.

So I did create a new post about it here…

HI ,

Sounds good. I’ll take a look as soon as I have a chance!