Mouse ScreenPosition to WorldPosition

Help and Feedback Code Review
#1

So as you know in order to convert the mouse’s coordinates from screenspace to worldspace you must raycast towards the mouse position.

There are a variety of ways roblox allows us to do this, but all of them seem to involve some deprecated system.

Mouse.Hit – Mouse class deprecated
Mouse.UnitRay – Mouse class deprecated, Ray object
ViewportPointToRay along with its brother ScreenPointToRay both involve creating a useless Ray object, which also may be deprecated

After those 3 options though, roblox doesnt give you any up to date way to convert from the mouse’s screenspace coordinates, to a worldspace coordinate. So I ended up having to make my own…

local function RaycastX(rayParams, distance) 
	assert(typeof(rayParams) == "RaycastParams")
	assert(type(distance) == "number")
	
	local viewportSize = camera.ViewportSize
	local theta = (camera.FieldOfView / 2) * (math.pi / 180) 
	
	local ar = viewportSize.X / viewportSize.Y
	local l = -camera.NearPlaneZ * math.tan(theta)
	local halfSize = viewportSize / 2 
	
	local mousepos = UserInputService:GetMouseLocation()
	mousepos = (mousepos - halfSize) / halfSize		
	mousepos = Vector2.new( mousepos.X * ar, mousepos.Y  )
	
	local front = Vector3.FromAxis(Enum.Axis.Z) * camera.NearPlaneZ
	local right = Vector3.FromAxis(Enum.Axis.X) * mousepos.x * l
	local up = Vector3.FromAxis(Enum.Axis.Y) * -mousepos.y * l
	
	local localized = camera.CFrame:VectorToWorldSpace(front + right + up)
	local localizedUnit = localized.Unit
		
	return workspace:Raycast(camera.CFrame.Position, localizedUnit * distance, rayParams)
end

While this method works, I was just wondering if this is a complete waste of time and I should just use either the Mouse class or use either one of the ViewportPointToRay or ScreenPointToRay, just because I don’t know if my method could be potentially slower than those ways, or just overall more code that takes a more convoluted route in order to do something that can be achieved the methods above much easier.

I don’t know, what are your opinions?

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Click SurfaceGui button through part
#2

One thing you should know is that Mouse is not deprecated, it has only been superseded by UserInputService. Mouse is still actively supported and maintained.

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#3

oh thanks I should have read the form more clearly. Although roblox still strongly recommends to find other alternatives to Mouse. Even moreso Mouse.hit only allows 1 singular object in its filtering list, which might end up biting me in the past if I wish to cast multiple objects to my mouse.

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