Is it Worthwhile to Export Unions into Mesh Format?

[Choco_Iate (Chocolate)]

As the header suggests, I’m wondering whether or not I should be exporting the unions in my games into a Mesh Format. I acknowledge that unions can be unreliable at times, but I don’t really know if I should spend my time exporting each union then re-importing as a mesh. Does it have a significant impact on performance, and does it really improve the experience of players? I’d hopefully like to have a pretty lag-free experience for players, so any help is great, thanks.

[Foxzes (Joshua)]

It only has impact on performance if you make an effort to optimize the mesh parts. Unions can indeed be unreliable, but they’re also easier to change within Roblox if you value that.

It shouldn’t matter much which option you choose unless your game has a lot of parts already (an existing poor performance on lower-end devices) or if you’re aiming to make your game super accessible, even to outdated devices.

[BloodSpring (David)]

Hey @Choco_Iate!

Quick Answer: No

In short, it’s better to have a greater part count that is adequately dispersed and spaced out than it is to have a lower part count that is primarily composed of un-optimized meshes or unoptimized meshes.

A lot of people forget what unions are made for originally, they’re to create advanced objects that couldn’t have been made prior with ROBLOX primitives (parts, wedges, spheres, cylinders). There are many usecases for unions, however the usecase you’re defining isn’t going increase the performance of your game.

Additional resources I’ve written in the past that also help answer the question:

How many parts is "too many"? When is geometry optimization overkill?

Hey CloakedYoshi! Brick Count is Not the End All Be All < Explanation: When you have an excess of parts, all that happens is it increases the loading time, it doesn’t necessarily decrease player performance. If you follow these conditions you can definitely stretch out the amounts of parts you use in your game: Conditions: Not crowding your parts in the thousands into one area, this’ll overwork the player’s ability to render. Please try your best to space them out accordingly or heck, eve…

Any good and effective way to significantly reduce lag in my game?

Hey RapidBoss08! A quick analysis of the on surface detail of your game! Analysis: It contains 98,145 parts Although you claim they’re all parts, I am left dubious with this picture. https://i.gyazo.com/243ce13e9853d54fec1768d1aee467e1.png It clearly feels like CSG due to the shading, sharpness, and poor hitboxes. Solution Try dispersing your trees more some the player doesn’t have to render so many triangles in one setting. I do agree the streaming enabled will help with the rend…

Conclusion

Don’t throw computer generated geometry into another software, and throw in back into ROBLOX and expect good results without actually editing the meshes. Good luck, hope this helped!

[mer5000]

As far as I understand, unions and meshes instance the same. Importing/exporting unions as a result would not change performance.

It may be better to have them as a mesh to avoid issues with unions disappearing (if that’s still a thing.) Maybe if you want to optimize your union in Blender, it may be easier than in Roblox (but I have never done this, so this is speculation.)

Importing/exporting unions to Blender and then back to Roblox as meshes has a main advantage (as a builder) of being able to scale it as a mesh, not as a union which scales as a model.