How precise is PreciseConvexDecomposition for unions?

I was wondering since i have many things in some games that can be unioned should I?
Especially with something like this:

It’s a relatively simple shape and i think i should union it, to move it around easier.


You could union it, but that would mean extra unnecessary geometry that will have an effect performance. You would also probably have to set the collision fidelity to something more precise. If the only reason you want to union it is for easier movability, in this case, it would probably just be better to group all of the parts into a model. This would also allow for easier customization of materials and colors later on if you need to do so. And to answer your question in the title, PreciseConvexDecomposition should be precise enough for your case, but I recommend you just group the parts instead.

Ok, thank you.
Now to constrain all of the parts :pensive:

Oh, I did not realize they were moving. It would be fine to union them, then. To make up for the extra geometry, you could go into a software such as blender and use the decimate modifier to remove the extra geometry created by the union.

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I never thought about that!
But how do you export union as obj file?

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In the explorer window, find your union, right click it and click “export.” This will allow you to export the union as a .obj file to your computer which you can import to blender.

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What do i do now?
also it looks off.
Anything i try warps the shape in weird ways.

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Actually you don’t need to union it in the first place. Just select and export all of the parts you want to union into blender and then re-import them but make sure you import them all as one mesh. This way you don’t have to deal with the extra geometry created by the union. (Sorry for the late response)

Ok, does this still apply if negative parts are used?

If you are using negative parts, you might be better off using blender’s Boolean modifier. You would have to export the parts you want as separate files and then import them to blender all in one file. Then, you would use the Boolean modifier on the part that you want to negate and the other part(s). The Boolean modifier is basically the same as union/negating, but I believe it is more efficient and creates less extra geometry. If you don’t know how to use the Boolean modifier, I suggest you look on Google or YouTube for resources.

Ok gonna tried that, i installed blender but didn’t really used it after realising it’s more complicated than a washing machine lol.

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