How can I detect characters near on a ray?

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#1

Currently, I am making a FPS system where when the player shoots a ray will go through the Ray.new(player.Character:FindFirstChild("Head").Position, mouse.UnitRay.Direction.Unit * 300) And now I am trying to find characters near the ray I casted

Let’s say the ray goes like this:
image

It is not going to be detected because it did not hit the character BUT what I would like to do is to make the character DETECTED by the ray.

Are their any ideas I can use?

This is my current code:

  for _, charactersaffected:Model in pairs(workspace:GetChildren()) do
		if charactersaffected:IsA("Model") and charactersaffected:FindFirstChild("Torso") then
			local newray = Ray.new(player.Character:FindFirstChild("Head").Position, realhit.Direction.Unit * 300)
			local distance_character = newray:Distance(charactersaffected.PrimaryPart.Position)
		end
	end
#2

how about raycasting a shape with raycasting a ray?
what i mean is:

  1. raycast the shape to detect characters near a ray
  2. raycast the ray to detect the hit part of ray
#3

The easiest way would be to get the ray to hit the thing. Try using shapecasts for a wider ray, or weld an invisible hitbox part to each character and detect hits on that instead.

#4

Well, you can use a raycast to determine the endpoint, and use :GetPartBoundsInBox() to make a really long hitbox.

#5

You need to calculate the distance between each player and the ray. If the player is below a certain distance then you should count that as being “detected”. Here is some code that will allow you to do that

local DETECTION_DISTANCE = 20 -- Under this distance a player will be detected by a ray

local function getClosestPointOnRay(ray: Ray, point: Vector3): Vector3
	local toPoint = point - ray.Origin
	local alpha = toPoint:Dot(ray.Direction.Unit)
	local pointOnRay = ray.Origin + ray.Direction.Unit * alpha
	
	local direction = (pointOnRay - ray.Origin).Unit
	local length = (pointOnRay - ray.Origin).Magnitude
	
	--Rays mathematically have infinite length so we need to limit this to our preferred length
	if direction:Dot(ray.Direction.Unit) < 0 then --Dont allow going behind the ray
		return ray.Origin
	elseif length > ray.Direction.Magnitude then --Dont allow going beyond max length of ray
		return ray.Origin + ray.Direction
	else
		return pointOnRay
	end
end

local function isDetectedByRay(ray: Ray, point: Vector3): boolean
	local closestPoint = getClosestPointOnRay(ray, point)
	local dist = (point - closestPoint).Magnitude
	
	if dist <= DETECTION_DISTANCE then
		return true
	else
		return false
	end
end

To implement this, iterate over every player and call isDetectedByRay. Provide it the ray and the position of the player