What are you attempting to achieve? (Keep it simple and clear)
I’m thinking of using unions in a game. In this game unions will play a major role.
What is the issue? (Keep it simple and clear - Include screenshots/videos/GIFs if possible)
Unions have a history of corrupting. I have had situations where all the unions in my game got corrupted and I was only able to get a few back. Are unions really reliable? Should I rely on them?
What solutions have you tried so far? (Have you searched for solutions through the Roblox Wiki yet?)
Well, I have had cases where unions have worked fine. I can blend the things I would use unions with but it would take longer for me and it will be harder since I have just begun using bender a few months ago. Unions don’t corrupt often but when they corrupt in very complex unions which took a lot of effort, it can be really annoying and time-wasting.
In my opinion, I wouldn’t use unions for very complex buildings or very large builds because they do corrupt and can cause a lot of frustration when trying to use them, I suggest getting more experience with blender rather than using unions to make complex builds.
The actual use of unions is to turn a group of parts into one part. You’d better do this when, for example, you want to put the same script into a group of parts simultaneously. However, unions can not contain parts with different materials. They also can contain normal bricks - not wedges, cylinders or spheres. So, as you can understand, only trust unions for small buildings.
Since unions are unreliable, I always duplicate the NegateParts and other stuff and put it aside, so that if the union is corrupted I can always get it back by unioning the stuff I put aside.
Unions have their ups and downs, one of the biggest things people dont use them for is becuase of the union corruptions. Its a issue most developers have and why they dont use unions. As a pro they reduce parts which could lead to less lag in some cases. I would use them for simple things. I dont use them that ofern.
I would say unions are reliable but if I would like to build something high-detailed I would go straight into Blender. However unions do corrupt sometimes as some people have said already.
Unions are useful when you want to make small objects of the same material, plus they are quite reliable. I use unions for details on buildings, or stuff like furniture, it just makes it feel cleaner for me without the overlapping parts.
Unions are a great finishing touch for adding windows and doorways etc however this should only be done once you’ve finished everything due to measurements getting messed up by unions.
The primary problem with unions is that, unlike individual parts, unions are created as an asset and are loaded to the game from the website. If you have too many unions, then you are loading so much data from the website that it will lag the game.
In addition, unions can create extra faces and triangles that you might not need which puts stress on the server. I use unions very sparingly in my newer games.
There was a time where people would union literally everything under the guise that ‘well its less parts so it must be better for performance’. This is obviously completely wrong and infact makes things worse.
The primary problems of union is that they can corrupt. This has been seen in many, many cases. There is a page in the DevForum explaining how you can recover corrupted files. Unions are only good for small things and I would highly advise not using them in big or detailed structures. Once again, if you really have to use unions, export them and import them as a mesh. I would only recommend using unions if you’re doing tools or doing small and unimportant things. Unions should never be used as a primary resource for advanced parts.
The way I see it, unions should be used in the same way that they are in Unreal Engine 4; as BSP brushes. I only use them to make basic shapes when I am blocking out my scene.
I’ve been using union for a small item until this day, mostly to fix the texture overlapping. And for me, the corruption event occur rarely. So i guess its fine using it as long as you use it for a simple thing that isn’t hard enough to replicate. I still use grouping on a big model though.
I sometimes make copies of some of my work before hand in-case the unions fail, unions sometimes work for me, but rarely. They often have bugs and in my cases are not reliable for big projects; I would use them for simple builds that aren’t too significant. You’re probably best going to blender.
Mmmmm… I say just learn how to use Blender. You’ll be better for it in the long term.
Not only that, but you can use Boolean Operations in Blender as well and with much greater control completely making Unions useless in the aftermath. They’re just not worth it whatsoever.
Only use unions when absolutely necessary. They are prone to corruption very frequently in my experience and don’t offer very many benefits over the alternatives.
Despite popular belief, unions are NOT always better on performance than a bunch of parts are. The geometry for unions is sloppy compared to what you can do by hand and will almost always have messy collisions and vertices which can lead to unexpected lag in your games. Along with this, the geometry data for roblox parts is already stored on the client so loading in several parts may actually be more efficient than an entire new union in a lot of cases. This issue compounds especially hard when you are using a lot of new unions in your place instead of duplicating existing ones. Going about unions this way can severely increase your load times and resource usage.
Personally I avoid unions wherever possible and usually only use them for objects that are relatively simple and have collisions disabled. If you absolutely must use a complex union, make sure you are duplicating it if you need to use it more than once and you should consider disabling the collisions to improve performance.
