If you're hunting for a roblox raycasting gun tutorial that actually makes sense, you've probably realized that using physical projectiles for everything isn't always the way to go. While shooting big, glowing fireballs is fun, most modern shooters—think Phantom Forces or Arsenal—rely heavily on raycasting. Why? Because it's instantaneous, it's precise, and it doesn't cause the physics engine to have a meltdown when fifty people start spraying bullets at once.
Raycasting might sound like some high-level calculus nightmare, but it's really just fancy talk for drawing an invisible line from Point A to Point B to see if it hits anything. In this guide, we're going to build a basic hitscan weapon from the ground up. We'll cover the setup, the scripts, and how to make sure you aren't just shooting yourself in the foot—literally.
Setting Up Your Tool and RemoteEvents
Before we even touch a line of code, we need a place for that code to live. If you've worked in Roblox Studio for more than ten minutes, you know the drill, but let's do a quick refresher.
First, go into your StarterPack and insert a Tool. Name it something cool, like "Raygun." Inside that Tool, you're going to need a few things: 1. A Part named Handle (this is what the player holds). 2. A RemoteEvent named "ShootEvent." 3. A LocalScript for the player's input. 4. A ServerScript to handle the damage (you can put this inside the tool or in ServerScriptService, but for this tutorial, we'll keep it inside the tool for simplicity).
The RemoteEvent is the most important piece of this puzzle. Because of Roblox's security (FilteringEnabled), a player can't just tell the game, "Hey, I killed that guy." The server has to be the one to decide if a shot actually landed. The LocalScript will tell the server where we're aiming, and the ServerScript will do the heavy lifting.
The Client Side: Capturing the Click
Let's open up that LocalScript. Its job is simple: wait for the player to click, figure out where the mouse is pointing, and tell the server to fire the ray.
We're going to use UserInputService or just the Mouse object. For a basic roblox raycasting gun tutorial, the Mouse object is a bit easier to grasp.
```lua local tool = script.Parent local player = game.Players.LocalPlayer local mouse = player:GetMouse() local event = tool:WaitForChild("ShootEvent")
tool.Activated:Connect(function() local mousePosition = mouse.Hit.Position event:FireServer(mousePosition) end) ```
That's it for the basics. When the player clicks, we grab the 3D position of the mouse in the game world and send it over the "bridge" (the RemoteEvent) to the server.
Pro tip: You might want to add a "debounce" (a cooldown) here later so players don't fire 1,000 bullets per second by using a click-macro. But for now, let's keep it lean.
The Server Side: The Raycasting Magic
Now, hop into your ServerScript. This is where the actual "ray" in our roblox raycasting gun tutorial happens. We need to listen for that RemoteEvent and then draw our invisible line.
When we use workspace:Raycast(), we need three main things: an Origin (where the bullet starts), a Direction (where it's going), and RaycastParams (the rules for the ray).
```lua local tool = script.Parent local event = tool:WaitForChild("ShootEvent")
event.OnServerEvent:Connect(function(player, mousePosition) local character = player.Character if not character then return end
local gunTip = tool.Handle.Position -- You could use an attachment here instead local origin = gunTip local direction = (mousePosition - origin).Unit * 300 -- 300 is the range local params = RaycastParams.new() params.FilterDescendantsInstances = {character} -- Don't hit yourself! params.FilterType = Enum.RaycastFilterType.Exclude local result = workspace:Raycast(origin, direction, params) if result then local hitPart = result.Instance local model = hitPart:FindFirstAncestorOfClass("Model") if model and model:FindFirstChild("Humanoid") then model.Humanoid:TakeDamage(10) print("Hit " .. model.Name) end end end) ```
Let's break down that math for a second because it trips people up. (mousePosition - origin).Unit gives us a vector that points from the gun to the mouse but has a length of only 1. We then multiply that by 300 to stretch that line out 300 studs. If you don't multiply it, your gun will only have a range of one inch. Not very useful in a shootout.
Making It Look Like an Actual Gun
If you run the code above, the gun will work, but it'll feel incredibly boring. You'll click, a health bar will go down, and nothing else happens. To make it feel like a game, we need visuals.
Normally, people use Beams or Trails for this. A quick way to do it is to create a thin Part that stretches between the gun tip and the point where the ray hit.
In your server script, after you confirm the raycast, you can create a temporary "bullet" part. Use the Debris service to make sure it disappears after a fraction of a second so you don't clutter up the workspace with thousands of tiny parts.
Wait, why the server? Actually, for a really smooth experience, many developers create the visuals on the Client. If you create the bullet trail on the server, there might be a slight delay between the click and the visual appearing because of ping. But, to keep this roblox raycasting gun tutorial simple, putting a basic visual on the server is a good starting point.
RaycastParams: Don't Shoot Your Own Gun
One thing that beginners often overlook is the RaycastParams. If you don't tell the ray to ignore the player holding the gun, the ray will start inside the gun's handle, hit the handle immediately, and stop. Your gun will essentially be hitting itself.
By using params.FilterDescendantsInstances = {character}, we tell the engine: "Ignore everything inside the player's character model." If you have teammates or a specific map layout, you can add those to the table too.
Handling Errors and Exploits
Since this is an informal guide, let's talk real talk: players will try to cheat. In our current script, we are trusting the client's mousePosition. A hacker could send a mousePosition that is 5,000 miles away or directly behind them.
To fix this, you should always do a distance check on the server. If the player is in the Spawn room and the mousePosition they sent is across the map, you probably shouldn't let that shot count.
Also, always check the origin on the server. Don't let the client tell you where the gun is; the server already knows where the tool.Handle is. By calculating the origin on the server, you prevent players from "shooting from their eyes" or shooting through walls they aren't even near.
Wrapping Things Up
Raycasting is one of those hurdles that makes you feel like a "real" scripter once you get over it. It's the foundation for guns, lasers, even custom interaction systems (like "Press E to open door" prompts).
If you followed this roblox raycasting gun tutorial, you should now have a working tool that can detect hits and deal damage. From here, you can add sounds, muzzle flashes, and maybe even some screen shake to give it that extra "oomph."
The best way to learn is to break things. Try changing the range, try making the ray bounce off walls, or try adding a spread factor to the direction so the gun isn't perfectly accurate. Coding is mostly just trial and error until something looks cool. Happy building!