I’ll see if that is the issue.
This is because hitboxes in unions are not prefect, please use a normal part when collisions need to be precise.
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Nope, didn’t work at all. It could be my unioning but I doubt that is the issue.
A normal part, what do you mean?
Just use a normal part for it then, do not use unions for that.
Can you provide an example for me to see.
The problem here is the Roblox union hitboxes, they’re huge, meaning you’re gonna need to use a normal part for it.
This is the icon of a part in Roblox studio:
Can you show me a building just by using a normal part, because I would need union and negate to make a space to walk in. Would you mean doing this, by using individual parts?
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Can you link us to the game?
Or show us in studio the part your having trouble with? It could be a mesh or a union that your talking about.
You can just place the parts individually and have the inside be hollow. You can also resize parts to make them small so they can be good for walls.
I suppose this will have to do. I could work with it. Thanks for trying to help me out though.
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What would be the best way to take a picture. I don’t really want to link the game cause it isn’t done but manly cause there is stuff spread out and kinda looks like a mess.
When you union something, you take a chunk out of a big part, and what this does is it creates individual triangles inbetween to represent this. However, unions are somewhat notorious for inaccurate physics hitboxes, and collisions are approximated so you may think you can walk through a doorway but actually the door way’s collision box is very simplified so its almost like a box.
To get around this issue, you can try divide your doorway into three separate parts rather than one whole part, and create an arch way like this:
As you can see, I’ve divided the doorway into three parts. Two normal parts on their own, and one union “archway”. I hope this helps and feel free to message me with any questions.
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So instead of union and negating, just build with parts instead? Also, how would you make the arch, its pretty well defined. Is it a result of union and negating or is with a plugin?
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The parts outlined in red are normal parts, the part in blue is a union.
Actually never mind about the arch. I see it now.
The version of your mesh/CSG that the physics system uses for collision detection is often lower-fidelity than the visual mesh. If you do a lot of CSG, get this plugin to easily toggle on and off the setting to show the convex decomposition of your mesh (the physics geometry you get for collision mode Default). You can see your mesh’s Hull and Box options visualized with this on too.
Often, if you use CSG to cut holes in a part, they will not be the shape you expect in the physics mesh. They can even seal up entirely (something you’ll see if you try to make a lot of window holes in a big wall with negate operations).
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I’ve had this exact issue with unions, They can be touchy when it comes to collisions after negating an area.
I can’t be much help as to exactly how I fixed the issue but if I remember correctly the negate part should have can collide off and you either need to select main first, then negated to union or the other way around.
It works but can be a pain in the arse. Lucky thing we have Blender and Maya huh