Does doing this actually make less lag?
I have a game im working on and before i knew unions were bad to use some of my friends and myself used unions so besides going in and fixing each union which would take ages does converting a union to a mesh ACTUALLY help with lag?
The method i would use to convert unions would be exporting the union and reimporting to roblox to be a mesh.
Yes, it does. To my understanding, meshes are saved to servers, so it shifts stress from client-side to server-side. Most meshes shouldn’t give you too much network traffic, and meshes are also more flexible - so unless you have a game that already has a lot of meshes in it, it helps with lag significantly.
As already said, it does.
As a test, I made a small build and added a lot of unions and it was extremely laggy.
Then, I made the exact same build but with MeshParts and it was not laggy at all.
You converted the unions to meshes by exporting the union and reimporting to roblox?
No, I made the unions into meshes in blender.
So like, I saw how I made the union in Studio, and made it in blender.
Would it have the same effect by just exporting the union and reimporting to roblox to convert it to a mesh? Because thats what im trying to do.
Something that also helps reduce lag for both Meshparts and Unions is changing the Collision Fidelity to something easier to process. This is useful for Meshparts or Unions that aren’t going to need a precise Collision box, so setting a complex union to something like “Box” will help out a lot.
I don’t really know. You can try.
Yeah, that does. Like I said all it’s doing is shifting rendering RAM usage over to network usage. Obviously, cleaning up unions after performing them in Studio would help greatly, but based on my testing converting unions or parts to meshes significantly improves performance.
This is probably one of the most forgotten about performance enhancements you can do. Setting collision fidelity to ConvexDecomposition can fix physics bugs, and likewise you can switch them to another fidelity option and improve performance for objects that aren’t colliding with anything or won’t interact with another object. Roblox is built as a ‘physics engine’ rather than a game engine, so every time you get an interaction between objects it has to calculate the physical properties that should change. On games with lots of parts, this can help a lot.
Converting unions into meshes doesn’t do anything by itself. However, you can import the union into Blender, optimize it by merging duplicate vertices (Highlight all vertices in edit mode with A → Ctrl + M → Merge By Distance) and exporting that mesh and importing it into Blender.
That messes up the shade smooth and makes it look weird.
I’ve done that with a few unions and they always come out fine. If for some reason the smooth shading stops working, go into object mode, right click → shade smooth. If it looks kinda messed up, make sure to use auto smooth under Object Data Properties.
Thank you. Finally someone who understands mesh optimization. Theres so many people that make a 100k+ tri model in blender and think its not going to lag whatsoever because of the sole purpose it was made in blender.
Roblox unions can be easily just as good as blender meshes if devs know how to properly optimize.