I’m a CAD designer and i’m using UE4 to design a game in my spare time, after a few days i’ve almost got my workflow for taking a CAD part/assembly from autodesk inventor into UE4, still have a few kinks to work out but it does work. Whilst i’ve been doing this i’ve been trying to figure out what is best to do but cant seem to find the answer online, simply put if i make a load of parts and import those multiple meshes into UE4 and then join them up within the engine (could make a group), is this better or worse than if i joined everything up before hand and imported just one mesh?
The reason i’m asking is i compared both ways in terms of polygons and they had the same number, so i thought i would ask before i end up importing and joining alot of stuff then suffering later on having to redo everything in one way of the other.
Actually it depends on which kind of meshes and map you are using/building (building, small props,…) -> because when you import them separately, you can cull them + all of them have a own lod channel.
It also depends on the lighting you want to go for. For instance, you cant just merge meshes if you want to use static lighting since it would mess up the lightmap UV’s.
There are definitely different considerations here.
As pointed out there are performance issues that you can experience by not having the ability to cull meshes and use LODs for parts of the assets that aren’t being rendered.
Another consideration as well is that when you import multiple objects and combine them on import the UVs will combine as well. This can lead to unintended materials being applied and will give errors for Overlapping UVs for the second UV for lightmapping.
You will find a lot of devs will import their meshes as individual objects and then use the editor for placement. This will give you the most control and flexibility for your assets.
There are always situations where it would be good to do the former though. Once you start getting your game going do a test with a few assets and see what results you get. If you like one over the other go with what works best for you!
