Build: v1.9.14 Mode: All Reproducibility: Always Severity: Major Type: Block Collision Summary: Large structures using many complex blocks will lose collision Description: As of v1.9.14, when building very large bases (possibly CV's as well) using a large amount of blocks with complex collision (like Corridor Elements), the base will lose collision in parts of the structure. My Blueprint is a perfect example. It worked fine before v1.9.14, but is still broken in the latest. Steps to Reproduce: 1) Download The Medieval Castle by Achenar off the workshop: https://steamcommunity.com/sharedfiles/filedetails/?id=2873796698 2) Create a new Solo Creative game 3) Spawn the Medieval Castle Blueprint on a Planet 4) Walk through the front gate, up the front stairs, and through the double doors into the great room. 5) A few meters in, you will fall through the floor. Collision is broken through about half the castle. Medieval Castle by Achenar: https://steamcommunity.com/sharedfiles/filedetails/?id=2873796698 Screen of staircase to walk up: This is where you will fall through:
I did some tests and I confirm this issue. Seems at least for two levels the collision is missing. The player ends two levels down from the great room, in the dungeon where the container expansions are installed. This might be bellow planet surface, depending on how the structure is spawned.
There are a lot expensive blocks placed on this structure such as the "Corridor Wall A" "Wall Edge Round" & when so many are placed you will reach the unity engine 65k vertices limit easily. I'm afraid we can't really help much more than tell you that you will need to reduce the amount of these blocks until the issue goes away or an alternative idea could be to cut the base into 2 or more separate bases (use the copy & paste tool to copy/cut large sections of the base & paste them to a base starter block) then spawn in next to each other & try to line them up.
I am curious what changed between 1.8 and 1.9, as it worked fine in 1.8? I certainly was running into issues while building it, and toned back some of those pieces when I lost collision.
I can check again soon (this won't be a high prio at the moment though) but I think in the past you possibly got lucky it didn't trigger sooner.
Update: this wasn't actually the unity chunk limit but a slight regression from a previous change & we have a fix for this coming in a future release. When rechecking myself I no longer fall through the problem areas of this BP.
Oh fantastic, that is great to hear! I would be fascinated to know the specifics (I'm a software engineer, specializing in Unity), although I recognize that may be information not available publicly. Regardless, thanks so much for looking into this!
