Trying to get an angle through the dot product, what's wrong with my script?
local Guard = script.Parent
local GuardRoot = Guard:WaitForChild("HumanoidRootPart")
local GuardHumanoid = Guard:WaitForChild("Humanoid")
local Player = game.Workspace:WaitForChild("SneakySecretAgent")
local PlayerRoot = Player:WaitForChild("HumanoidRootPart")
while true do
wait()
local PlayerPosition = PlayerRoot.Position
local GuardFace = GuardRoot.CFrame.lookVector
local PlayerFromGuard = PlayerPosition - GuardPosition
local Product = GuardFace:Dot(PlayerFromGuard)
local Cos = math.cos(Product)
local Angle = math.acos(Cos)
end
Basically the dot product part works well (hopefully), as I'm trying to see if the a guard can see the player, which in turn means I need to use the dot product to check how much the guard is facing the player.
Problem is, I want to reduce the sight of the guard, but I need to get the angle using the dot product. My script doesn't seem to input the correct angle.
Thanks in advance
1 answer
I looked up the formula for the angle between two vectors here (since you are trying to get the angle between the guard's line of vision and where the player is in relation to the guard): http://www.wikihow.com/Find-the-Angle-Between-Two-Vectors
Here is the implementation of that formula (I tested it and it works) in Roblox-lua:
function AngleBetweenVectors(a, b)
return math.acos(a:Dot(b) / (a.Magnitude * b.Magnitude))
end
Note that it's giving it to you in radians, so if you want degrees you'll want to apply math.deg to it. ex:
print(math.deg(AngleBetweenVectors(Vector3.new(1, 0, 0), Vector3.new(5, 0, 5)))) -- prints a number very close to 45
0