How would I go about making an AOE Cone Spell like in All Star Tower Defense

[xZylter]

You would need to apply a rotational offset, in your case 180 degrees. Simply adding that offset to the value should rotate the cone.

local OFFSET = 180

function mainFunctions.isInFOV(rootPosition, enemyPosition, FOV)
	local distance = rootPosition - enemyPosition
	local radians = math.atan2(distance.Z, distance.X)
	local degrees = math.deg(radians) + OFFSET
	
	if degrees > 180 then
		degrees = -(360-degrees)
	end
	
	local degrees = math.abs(degrees)

	if degrees < FOV/2 then
		print("true")
		return true
	else
		return false
	end
end

[kylerzong]

local function IsInFov(Anchor, Target, Fov)
	if not (typeof(Target) == "Vector3") then
		if not Target:IsA("BasePart") then return end
		Target = Target.Position
	end
	if not (typeof(Anchor) == "CFrame") then
		if not Anchor:IsA("BasePart") then return end
		Anchor = Anchor.CFrame
	end
	local A = (Anchor.Position - Target).Unit
	local B = -Anchor.LookVector
	local dp = A:Dot(B)
	return(dp > math.clamp(90-Fov, 1, 90)/90)
end

FOV.rbxl (28.4 KB)

[Padrox_x]

So guys I’m back.
I made much more tests to understand what is wrong.
Here is the test I made:
(kylerzong’s code)

(xZylter’s code)

I made four groups of balls located on the x Axis and z Axis. As you can see one group is on the -z, an other on +z, another on the -x and the last one on the +x.
The mid part is the rootPart, we can considerate it like Sasuke.
As you can see, we can see a first difference.
For both screen the FOV is 35 degrees but the Kylerzong’s code seems to give a bigger FOV than 35.
Now, I rotated the rootPart by -90 degrees and here is the result:
(kylerzong’s code)

(xZylter’s code)

So we can think it’s working but let’s rotate the rootPart again by -90.
Here is the result:
(xZylter’s code)

(kylerzong’s code)

So as you can see the rotation is kind of messy.
In the kylerzong’s code, the FOV isn’t 35 degrees but it looks like it take into account the rotation of the rootPart. In the xZylter’s code, it looks like to be 35 degrees but it’s doesn’t care about the rotation of the rootPart, only working on Positive x and z groups.

How about those results? Howdo you think I can do to solve this?
Thank you for your advices!

[kylerzong]

When inputting the fov into the function in my script you would put 35/2

I believe you are doing:

if that’s not the case then you could just play around with the values until you get the fov you want, I tried to relate the fov variable to degrees by just playing around with it

[Padrox_x]

Ok so I just have to divide the FOV by two when I input it in the function?
Mh, Do you know how I make the two lines to show the cone like in the screen shots of all star tower defense.
I think I’ll try to place two parts and to weld them with the character, then they will rotate with the character but I don’t know how to place them, how to have the position of each border of the cone.