how do I check if a vector3 value is in a region3 value in Roblox Studio? - roblox

Question

I am making a game with a building system. I am trying to add land ownership to my game by creating a region around a person's tent. The issue is that I have no idea how to check if another player is placing something in another player's land. Does anyone have an answer?

Answer 1

A Vector3 is essentially just a coordinate with an X, Y, and Z component. The assumption here is that its origin is at (0, 0, 0).
A Region3 is an axis-aligned bounding box that is constructed based on a minimum Vector3 coordinate and a maximum Vector3 coordinate.
A Vector3 can be considered inside the Region3 if its magnitude is greater than the minimum coordinate and less than the maximum coordinate.
Since the Region3 gives you the center of the region as its CFrame property, you can calculate the extents of the Region3 using its Size divided in half, and then check if the Vector3 falls inside that region.
local function isVect3InRegion3(vector, region)
-- validate input
assert(typeof(vector) == "Vector3")
assert(typeof(region) == "Region3")
-- get the dimensions of the region
local regionCenter = region.CFrame.Position
local regionHalfSize = region.Size * 0.5
-- calculate the extents of the region
local lowerLeftCorner = regionCenter - regionHalfSize
local upperRightCorner = regionCenter + regionHalfSize
-- check if the vector is inside the extents
local isBeyondLeftCorner = (vector.X >= lowerLeftCorner.X) and
(vector.Y >= lowerLeftCorner.Y) and
(vector.Z >= lowerLeftCorner.Z)
local isBeforeRightCorner = (vector.X <= upperRightCorner.X) and
(vector.Y <= upperRightCorner.Y) and
(vector.Z <= upperRightCorner.Z)
return isBeyondLeftCorner and isBeforeRightCorner
-- NOTE : comparing individual values above is less expensive than
-- return vector.Magnitude >= lowerLeftCorner.Magnitude and
-- vector.Magnitude <= upperRightCorner.Magnitude
end