I want a random part generator, but instead of hard coded XYZ placements, I want the parts to spawn inside of a part. I found this script that kind of does the job:

while wait(2.5) do
local Part = script.Parent
local Speed = game.ServerStorage.Speed_Orb:Clone()
Speed.CFrame = Part.CFrame * CFrame.new(math.random(-Part.Size.X/2, Part.Size.X/2),math.random(-Part.Size.Y/2, Part.Size.Y/2),math.random(-Part.Size.X/2, Part.Size.X/2))
Speed.Parent = workspace
wait(2.5)
Speed:Destroy()
end

(I modified it to do what I need by the way.)

but sometimes, the part spawns outside of the region, it actually happens a lot. Is there a better alternative to this method? Or is it just a small flaw.

A little different from the way you were doing it, but it does keep all the parts inside the region. Here is the code. You’ll need to modify it to fit your needs.

local function CreatePart()
local NewPart = Instance.new('Part', workspace);
NewPart.Anchored = true;
NewPart.BrickColor = BrickColor.Random();
NewPart.Size = Vector3.new(1,1,1);
NewPart.Material = Enum.Material.SmoothPlastic;
return NewPart
end
local function CreateRandomPosition(Part0, Part1Size)
local PartPos = Part0.Position;
local PartSize = Part0.Size;
local r = math.random;
local Boundry__x0 = (PartPos.X - PartSize.X/2) + Part1Size.X/2;
local Boundry__x1 = (PartPos.X + PartSize.X/2) - Part1Size.X/2;
if Boundry__x1 < Boundry__x0 then
Boundry__x1 = Boundry__x0 + 0.05
end
local Boundry__y0 = (PartPos.Y - PartSize.Y/2) + Part1Size.Y/2;
local Boundry__y1 = (PartPos.Y + PartSize.Y/2) - Part1Size.Y/2;
if Boundry__y1 < Boundry__y0 then
Boundry__y1 = Boundry__y0 + 0.05
end
local Boundry__z0 = (PartPos.Z - PartSize.Z/2) + Part1Size.Z/2;
local Boundry__z1 = (PartPos.Z + PartSize.Z/2) - Part1Size.Z/2;
if Boundry__z1 < Boundry__z0 then
Boundry__z1 = Boundry__z0 + 0.05
end
local RndPos = Vector3.new(
r(Boundry__x0 * 100, Boundry__x1 * 100) / 100,
r(Boundry__y0 * 100, Boundry__y1 * 100) / 100,
r(Boundry__z0 * 100, Boundry__z1 * 100) / 100
)
return RndPos
end
while wait() do
pcall(function()
local Prt = CreatePart();
local Pos = CreateRandomPosition(workspace.Part, Prt.Size);
Prt.Position = Pos
end)
end

Alright! I will say, I did run into a bug while making this, and error will throw if the x,y,or z sizes are less than the size of the brick. Let me know if this is an issue and i’ll find a fix.