Roblox Studio build 0.578 has broken single sided mesh collision/touch events

[Riptcage]

What is the problem?
Roblox Studio build 0.578 from today 5/31, has broken single sided mesh collision/touch events with collision set to Default or PreciseConvexDecomposition, but Box works.

Confirmed CanCollide is on
I’ve confirmed CanCollide is still on for humanoid player, and CanCollide is turned on the single sided mesh. (which is also set to be double sided)

Check video for Simple Repro

This video includes toggling to see “Show Decomposition Geometry”

Steps to Repro

1. Create a new roblox file
2. Import simple single sided mesh from FBX file
   singlesidedmesh.fbx (18.3 KB)
3. Place it in world
4. Set the object to double sided.
5. Walk through it with Default collision settings
6. Walk through with PreciseConvexDecomposition
7. Set to Box to actually collide

Why isn’t this in the bug reports section?
I don’t have credentials or regular rank yet

Please post this for me in Studio Bugs - Developer Forum | Roblox #bug-reports:studio-bugs if you can repro!

thanks!
-R

[TheRealAnonymousDude]

That is really weird but I think it has an issue running it because a Blender plane basically has no geometry. I would say go back to Blender and add the solidify modifier and you shouldn’t have that issue.

[Riptcage]

Nope. This isn’t a blender plane. It is polygons. If you load the fbx file in blender, you’ll see that. This was working 5/30 and prior, always. You can also see the collision exists in Roblox with the toggle in the above vid. If it had no mesh, we wouldn’t see anything. It simply just does not work anymore. Could someone with permissions post it in Studio Bug Reports please?

[subcritical]

Dupe of Vehicles sinking or falling out of the world when driving over certain parts after recent Roblox update
This should be fixed. Let us know if it’s still happening.

[Riptcage]

I’ve tested this and collision is working as expected now. Thank you very much!