Collision Service

Feature Requests Engine Features
#1

Basically, a service that provides easily accessible functions that allow us to check for collision on the “3d lvl.”

Function to check collision might go like this:

CollisionService.checkBlockCollision(Part,ListOfPartsOrASinglePart)

or

CollisionService.checkBlockCollision({Size,CFrame},ListOfSizesAndCFramesOrParts)

In the future, listofparts could be a collision layer, when roblox adds that. Or could be tags, again, when it is added.

Types of collisions detections that can be made:

Block, Sphere, Cylinder, Pyramid, Unions, Mesh, etc.

Note: I know that you can currently do something like Part:GetConnectingParts() or Part.Hit, but I don’t think those fire if you cframe them.

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#2

Have you tried playing around with this?

http://wiki.roblox.com/index.php?title=API:Class/BasePart/GetTouchingParts
(not the same as GetConnectedParts)

It works fine for anchored parts that are being cframed too, you can implement the whitelist stuff on top of it yourself

1 Like
#3

Yes, but sadly those parts have to exist before I can call such a method. And I can’t really control what it’s checking.

1 Like
#4

It’s relatively cheap to instance a part to check for collisions this way just for a split second (you don’t have to wait a frame before you can call GetTouchingParts). Not sure how many times a service where you can specify a hitbox without a part actually being there would be used. Can you explain your use case with a more detailed example?

#5

I wanted to do “theoretical” checks on the server without having to make a part. And I’ve heard it’s not cheap to make a part. But if it was cheap, I only want the server to make the part. But if I do, the client will also make the part.

EDIT: But you’re probably right. GetTouchingParts should do the job. It slipped my mind that they are able to do anchored checks.

#6

To be honest ROBLOX should really consider better solutions like what Unity offers in its Physics Lib and is similar to what you suggested
https://docs.unity3d.com/ScriptReference/Physics.html

2 Likes
#7

I’m doing collision checks in Lua for the house editor I’m working on. The math gets pretty intense but it’s worth the extra control

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#8

Is it a grid based system? If it is, you can use 2d collision checks on the base of the object, unless your house editor is more advance than I’m imaging it rn. :stuck_out_tongue:

#9

No it does cuboid intersection, raycasting, and wall cutting in Lua

https://devforum.roblox.com/uploads/default/original/3X/0/3/037796063f223cd7fd9136ffdce59b583695f0e7.gif

https://devforum.roblox.com/uploads/default/original/3X/e/1/e151d80ca9f8e99afa8311cd2a16c89bae705b32.gif

6 Likes
#10

Dang, that’s so cool. The browser crashed 6 times on me while I was trying to post this because it’s too amazing for my pc to handle. xD

#11

I’d suggest using this: http://devforum.roblox.com/t/3d-collision-detection/13697/13

#12

Use cases for this typically involve frequent usage, so performance would be substantially better using an API built in C++ rather than a user module implemented in Lua.

#13

Yes, but for the mean while, you can use this. Better than nothing and that module is very efficient.

2 Likes