Prerequisites

Before starting this guide you will need a working multiplayer Unreal Engine 5 project and a source build of Unreal Engine.

What is a Dedicated Server?

A dedicated server, in game development terms, is a computer that can run a standalone piece of software which only handles the game world and server code.

It does not spawn a player character and does not count as a connected player.

The first method when setting up networking in a multiplayer game for many is a listen server.

A listen server is perfect for many styles of multiplayer games as it works well with games with small player counts per server (2 to 16), keeps costs down for developers and make developing features easier with faster testing between two clients.

For some games this isn’t ideal as players might cheat, have sync inconsistencies between clients that would be game breaking (fighting games over large latency) and larger scale games causing the host machine to slow down impacting other player’s experiences.

Dedicated servers are perfect to remedy these issues. Running the files that we will be creating on its own machine, with ports setup correctly, will only process your game world and keep an server of your game running 24/7.

Automatic Session

We need our server to automatically create a session and then load the map on launch.

In our example project, which can be downloaded in a first person or third person format, we create our MainMenu widget and add it to the screen in our main menu level blueprint.

We need to adjust this so if it is a dedicated server then we ignore the menus entirely and create a session for our players to join!

To achieve this, we simply add a branch and an “Is Dedicated Server” node before our widget creation.

This is then connected together on the False pin as we don’t want the code to run if our platform is “Dedicated Server”.

On the True pin we then add a Create Advanced Session node with our desired settings.

If our session creation was a success we then open our level with the option ?listen so that our server can accept connections to the map.

Lastly, we compile and save our changes!

Choosing the Default Server Map

By default our dedicated server loads into an engine map called “Entry”. We need to change this to our own map to ensure that we can load players into the game.

Firstly, open the edit menu in the top left and then click Project Settings.

We then click the “Maps & Modes” section of the Project Settings.

We then click the Advanced drop down option in the “Default Maps” section.

Finally, set the “Server Default Map” option to the map that you want to start your server on. In this case we are using our “menu” map and making changes later in the guide to add dedicated server functionality.

No Default Character in the Level

As we are using a dedicated server, we no longer need a character spawned for the authority (server host).

Our level has a character blueprint inside of the level that gets controlled by the first player connected.

We need to remove this to prevent a character standing in the level with no player!

The Project Launcher

The project launcher is a built in tool of Unreal Engine that allows you to build versions of your game based on profiles that you can create.

One of the abilities of the project launcher is the dedicated server!

We can open the project launcher by opening the Tools menu at the top of the editor window and selecting the Project Launcher in the tools section of the menu.

You should now see a large empty menu! We now need to add our custom profile for our game!

We need to create our custom profile to specify to the engine that we want a dedicated server build.

Creating the Custom Profile

Firstly, click the Add button in the bottom right, then click “Create Custom Profile”.

You should now see a large menu of options appear.

In the cook section, we need to open the drop down menu and change “On the fly” to “By the book”.

We then scroll down the Cooked Platforms list and find the server platform we want to build for. For this guide we are building a dedicated server for Windows.

You can choose LinuxServer if you need an x86/64 Linux server or LinuxArm64 if you want to host your server on Linux Arm. If you do not understand this, simply choose WindowsServer.

We then scroll down further and select all of the maps that you want to include in your server. In this guide we have selected both of the maps in the Unreal Engine 5

Next in the Package section, click the drop down menu and change “Do not package” to “Package & store locally”.

This then generates you a default path inside of your project folder to build the server. This can be changed to anywhere you want using the directory picker “Browse” button.

Then, in the Deploy section, click the drop down menu and change “Copy to device” to “Do not deploy”.

Finally, we can give our new profile a name to remember what this Profile builds.

Creating the Dedicated Server

Now that we have our profile all setup, we can now build our dedicated server!

Click the back button to return to the main Project Launcher menu.

We can now see our new profile in the list of custom launch profiles.

Building the Files

To build the dedicated server using our custom profile, simply press the launch button (Controller and display icon).

You now see the process of your dedicated server automatically building!

Now wait until the process has completed. The first time you run your profile it can take a long time. Leave this to fully complete before moving onto the final step!

Testing the Dedicated Server

Now that our dedicated server has built successfully, navigate to the folder you selected earlier to see the executable.

If you left this option default in the previous step, the folder found in your project folder then Saved/StagedBuilds and then the platform name. In this case “WindowsServer“.

From here we can open our Server.exe to open the server. This will open in the background and is hard to monitor and close.

To make this easier to use, firstly create a shortcut in Windows for your server executable.

We then open the executable and add the “-log” launch option to the end of the target section. This will make the server open as a window and print any logging messages on to the screen.

Now open the shortcut to your server and text will fill the window. This is your server initializing and setting up a session for your players to join!

On the client’s view it now shows the dedicated server session!

Demonstration

With three clients open inside the editor and our dedicated server open, the clients can connect to the session and see each other move without needing a full client open to host the game!

Project Files

Conclusion

You now have a dedicated server of your game building with the ability to be connected to!

With this knowledge, you’re one step closer to launching a fully featured multiplayer game that performs well and delivers a consistent experience to players!

Further Reading

• Click here to read the Unreal Engine Dedicated Server Guide
• For more networking fundamentals click here for the UE Networking Overview
• It’s always great to read up on how to build projects based on our learning of the project launcher, Click here for the UE documentation on Building Projects

The post How to build a Dedicated Server for your Unreal Engine 5 Game appeared first on Couch Learn.

Online and LAN Support

Unreal Engine 5’s NULL online subsystem can not find sessions outside of the player’s local network.

To find and connect to sessions outside of your local network without a direct IP address connection you need to use a different online subsystem such as Steam.

Click here to read the documentation for the Steam subsystem

Creating our Widget

Creating the Widget Blueprint

To allow our players to create their own sessions and join others we need to create buttons and text on screen. In Unreal Engine 5 this is called a user interface widget.

Firstly, right click in the content drawer and create a Widget Blueprint

Click “User Widget” in the menu that pops up.

Now we have to name our widget blueprint. For this guide we named the blueprint “Session Widget”. You can name your widget blueprint anything you like but make sure to remember the name for a later step!

Finally, double click your widget blueprint and you will see the Widget Designer window.

Designing our Widget

When designing widgets, you can find all available widget elements in the left side Palette menu.

To start designing your session widget, simply search for Canvas Panel and drag it into the middle section of the window.

Next, search for Vertical Box and drag it into the middle section of the window. These layout elements will be the main structure of your widget.

From there find the details panel on the right side of the window. Click Anchors and select the center box option shown in the image below.

After setting the anchors correctly we can begin to set the size and position of our widget.

Below the anchors drop down, set Position X, Position Y, Size X, and Size Y to the values shown in the image below.

Now, in the Palette menu, create two buttons. These will be interactable by the user to create and join multiplayer game sessions.

So we can access the buttons in the next step, click the first button and change the name in the details panel to CreateSession.

Repeat this for the next button and name it JoinSession.

To show to the user which button is used for creating and joining we need to add text to the buttons.

In the Palette menu search Text and drag the text onto the button. As you can see the text appears on the button and automatically resizes it so it fits well.

After creating one text element for each button, change the Text value for each Text element in the right side Details panel.

Set the top button to Create Session and the second button to Join Session.

Now to improve the design of our buttons, select both buttons and in the right side Details panel set Padding to 15 and click Fill.

Now our widget buttons are neatly arranged and easy for the players to use.

Once you are done customizing your widget, click Compile and Save to ensure your changes are applied.

Finally, click the Graph button on the top right side. This will switch the Widget Designer to the Widget Blueprint editor ready to give functionality to your widget!

Hosting and Joining a Multiplayer Session

Creating and Hosting our Game Session

Now that we are in the Widget Blueprint editor, you should see your two buttons in the Variables section on the left.

Click the first button in the list.

Below you should now see a Details menu with all of the events available to your button.

We need On Clicked so click the big green box with the plus icon inside to add this event.

You should now see the On Clicked event for your button in the middle editor window.

Right click anywhere and type Create Session. Click the option in the menu that shows Create Session.

Now connect the nodes together using the white arrows as shown below.

Right click anywhere and type Get Player Controller. Click the option in the menu and connect this to the blue pin.

After the blue pin is connected, set the Public Connections number to the maximum amount of players you want per game session.

Opening Levels to Multiplayer

Right click anywhere, type and select the Open Level option and connect this node to the On Success pin.

To create a multiplayer game using your level, set the “Level Name” pin to the level you wish to play on. In our case, this is FirstPersonExampleMap.

Lastly, click the drop down arrow and into the Options text box type:

?listen

With these steps complete, the code should look like this.

This code sets the level up to listen for multiplayer connections as a Listen Server.

Connecting to your Multiplayer Session

Finding Sessions

Finding multiplayer sessions using Unreal Engine 5 blueprints is incredibly simple.

The Find Sessions node searches and finds the active game sessions for your players to join. It outputs different execution pins based on if it succeeded or failed. The session results are returned as an array.

If you aren’t familiar with arrays click here to learn about arrays in Unreal Engine.

Firstly, we need to create the On Clicked button event for our JoinSession button, as we did in the previous step.

From there, right click and create the Find Sessions and Get Player Controller nodes. Connect this node to the On Clicked event, connect the Get Player Controller node to the blue pin, and set Max Results to 100.

Max results is the amount of sessions it will try to find.

Joining the Session

Next, we need to create the Join session node and another Get Player Controller node. We could reuse the previous node but it makes the blueprints easier to read.

The Join Session node should be connected to the On Success pin on the Find Session node.

From the Results square pin, drag and let go to open the blueprint node menu. We can then type get and create a Get (a copy) node.

Finally, connect the Dark blue pin of the Get node and connect this to the Search Result input node.

Adding our Widget to the Screen

To make our widget show on the screen, firstly click the branch icon in the main editor window shown below.

In the drop down menu click Open Level Blueprint to open the Level Blueprint Editor.

Right click anywhere and create the Event Begin Play and Create Widget blueprint nodes.

Connect the white pins together and select your widget in the Class drop down box.

In our case we named the widget SessionWidget to make it easy to find in the drop down box.

Lastly, create an Add to Viewport blueprint node and connect the blue pins together. This will create our widget and then add to the game screen.

The final level blueprint should look like this.

Opening the Game Clients

For the last step we need to test our blueprint logic!

Unreal Engine 5 makes testing multiplayer in the editor extremely simple.

First, click the three dot button and, in the drop down menu, set Number of Players to 2. After that click New Editor Window to launch two windows of your game.

Once the two clients have loaded, click Create Session on one and Join Session on the other. After a short amount of time they will connect together in a multiplayer session!

As you can see in the demo below, the players can move around and see each other moving without any additional work! The template character in Unreal Engine 5 have multiplayer movement support out of the box.

Connecting to Sessions Outside your Local Internet Network

The session and listen server created in this guide can be connected to inside your local network by default and world wide through the internet with a few additional steps.

If you wish to host your session to global internet users, you need to port forward UDP/TCP 7777. Setting up port forwarding is different per router so check your specific router instructions.

If you don’t know what port forwarding is click here.

Download the Project Files

We create these free guides and resources on Game Development to give anyone the knowledge to make their own games. If you find these guides helpful please consider supporting us by purchasing our project files.

To improve your multiplayer sessions gameplay, we have bundled a session browser into the project files!

Conclusion

Your project can now create and join multiplayer sessions!

This guide was created to make the initial multiplayer setup as easy as possible. Unreal Engine 5 has extremely robust and powerful multiplayer tools to make any multiplayer game you want!

To learn more about replication and the session system, the Unreal Engine documentation is the best place to improve your knowledge about multiplayer development.

Click here to read more about Replication.

Click here to read more about the session system nodes.

The post How to use Multiplayer Sessions in Unreal Engine 5 appeared first on Couch Learn.

Prerequisites

This guide expects that you understand how to use basic nodes such as branch, get player controller and input actions / events.

If you do not know how to use input actions in Unreal Engine 4 click here to read our guide.

This guide also expects that you know what a line trace is and how to set them up for a first person style game.

If you do not know how to setup first person line traces click here to read our guide.

How Unreal’s Damage System works

How to Deal Damage

The most basic way to deal damage to another actor is to use the “Apply Damage” node.

Here are the important variables to set:

Damaged Actor – The actor that you want to damage
Base Damage – The amount of damage to apply to the damaged actor
Damage Causer – The actor that applied the damage to the damaged actor

How to Detect Damage

When added to any actors event graph, the “Event AnyDamage” event node runs every time the actor is damaged.

Here are the important variables to use from the event node:

Damage – The amount of damage that is detected
Damage Causer – The actor that dealt the damage

Creating the Weapon Damage Nodes

We recommend using the default First Person Shooter template for this guide.

This damage system works will all game types but when learning a new system it is easier to have a template that works well before you start.

The First Person Shooter template has a player character setup with movement, mouse aiming, arm and gun models and animations.

Requesting to Shoot to the server

Firstly, to make the weapon damage run correctly on multiplayer, create a new custom event called “Net Shoot Weapon”.

Then click the new event (Net Shoot Weapon) and in the detail panel on the right of the screen change the “Replicates” drop down box to “Run on Server”.

Changing this setting will now run this event from the client to the server. This prevents cheating as all damage and collision checking will be done server side.

Next create an InputAction Fire event (included in the first person shooter template) and create a Net Shoot Weapon node to the Pressed pin.

This will send a message to the server to shoot your gun and calculate the

Finally for this section to be complete, connect the animation and sound effect blueprint nodes from the template to the Net Shoot Weapon execution pin.

This complete section will look like this:

Syncing the Animation and Sounds

The animation and sound effects running on the previous step don’t currently run for other players.

To play the animation and sound for this player on everyone else’s screens we need to create a multi cast event.

Firstly, add a new custom event named “Multi Weapon Animation”.

And change the “Replicates” to “Multicast”.

Create a branch node, a Get Player Controller node and a Get Controller node.

From the Get Player Controller node create an equals node and connect the “Get Controller” node to the bottom pin as shown below.

The last nodes required for this step can be copied and pasted from the step above.

The complete section looks like this:

Server-side Weapon Shooting

Firstly, from the “Net Shoot Weapon” event created earlier in this guide, we need to create a “Multi Weapon Animation” node and connect it together.

This will sync the animation and sound to all clients on the server whenever a player shoots.

To damage another actor when the request is received, we first will need to use a Line Trace for Objects node.

If you do not know how to setup a line trace click here to read our guide on first person line traces in Unreal Engine 4

From the line trace we need to create an “Apply Damage” node and connect the “Hit Actor” pin from the “Break Hit Result” node to the “Damaged Actor” pin on the “Apply Damage” node.

Set the “Base Damage” value to the damage that you want your weapon to deal. (We used 15.0 in this case)

Lastly, create a Self node and connect it to the “Damage Causer” pin.

After all these steps, the line trace connections should look like this:

And here is the complete Net Shoot Weapon event blueprint nodes:

Receiving the Damage

Firstly create an AnyDamage event in the actor that you want to receive damage.

Create a new variable named “Health” with the type of float. This will be used to store the amount of health the actor has.

Set the default value of the “Health” variable to 100 (or whichever you want your actors max health to be)

Next create a Get node for Health, subtract Damage from Health and then set Health to this new value.

From the Set Health node create a “Less than or Equal” node, create a branch node and connect them together. This checks if the player’s health is less than or equal to zero after taking the damage

Finally, on the True execution pin create a “SetActorLocation” node and set the New Location value to where you want your actors to respawn when they run out of health.

Here is the complete Event AnyDamage blueprint nodes:

Demonstration

To visualise the health of the hit player easier we added a “Print String” node here:

Download the Project Files

Conclusion

Now your game or project has a fully multiplayer compatible damage system all using blueprints!

Expanding this System

To improve this system you could add a widget to the screen showing when a player is defeated and with what weapon they were defeated by.

Another way to improve this shooter style game would be to add attenuation to the shooting sound effects.

This would reduce the volume over distance and make the game more realistic. Click here to check out our guide on attenuation in Unreal Engine 4.

Lastly, try expanding from this guide by creating AI character with health and damage with our easy AI movement guide. https://couchlearn.com/easy-ai-movement-in-unreal-engine-4/

Further Reading

Unreal Engine’s blog post on their damage system: https://www.unrealengine.com/en-US/blog/damage-in-ue4#:~:text=Damage%20support%20is%20a%20feature,your%20damage%20model%20when%20needed.

The full damage blueprint node documentation can be found here: https://docs.unrealengine.com/en-US/BlueprintAPI/Game/Damage/index.html

The post Multiplayer Damage and Health System in Unreal Engine 4 appeared first on Couch Learn.

Using this system is very straightforward and only takes a few blueprint nodes to get working.

In this guide I will show you how to setup multiplayer in Unreal Engine 4 using the session system. We will setup a simple session and connect to it through another player.

Online and LAN Support

Unreal Engine’s default online subsystem can not find sessions outside of the local network the player is in.

To find and connect to sessions outside of your local network without a direct IP address connection you will need to use a different subsystem such as Steam.

Click here to read the documentation for the Steam subsystem

Starting a Multiplayer Session

Creating the Session

To start I created a simple widget with two buttons. One is host and one is play.

On the host button event use the create session blueprint node.

On the player controller pin, connect a “Get Player Controller” node and for the public connections pin set it to the maximum amount of players you want for this game.

Public connections is the maximum amount of players that can be connected to your server at once.

If “Use Lan” is checked the session you create will be only available on your local internet.

Opening Levels to Multiplayer

To create a multiplayer game using your level, add a new “Open Level” node and set the “Level Name” pin to the level you wish to play on. In my case this is FirstPersonExampleMap.

The important step is to click the triangle at the bottom of this node to expose the extra settings.

The “Absolute” checkbox and the “Options” text box pins are now visible. In the Options pin type exactly:

?listen

This code sets the level up to listen for multiplayer connections as a Listen Server.

With these steps complete, the code should look like this.

Connecting to your Multiplayer Session

Finding Sessions

Finding sessions using blueprints is simple. The Find Sessions node handles all this for us. It outputs different execution pins based on if it succeeded or failed and the results that it found as an array.

If you aren’t familiar with arrays click here to learn about arrays in Unreal Engine 4.

To start I created the Find Sessions node attached to the Play button in my widget.

On the player controller pin connect a “Get Player Controller” node and the Max Results pin is set to 100.

The Use Lan checkbox, if checked, will only search for sessions in your local area.

Joining the Session

To join a session in Unreal Engine 4, create a Join Session node.

This node requires the player’s controller and a session from the Find Sessions array in the previous step.

Firstly I will create a Get Player Controller node and attach it to the Join Session node.

From the Results output pin of the Find Sessions node in the previous step I created a Get node. This will find the first session in the list.

This is then attached to the Search Results input pin of the Join Session node.

Finally, the Join Session node is attached to the On Success execution pin of the Find Sessions node.

Opening the Game Clients

In Unreal Engine 4, there is a drop down menu next to the play button which gives you access to multiplayer options.

On this menu make sure “New Editor Window (PIE)” is selected and the “Number of Players” slider is set to anything above 1.

Next, click the Advanced Settings button at the bottom of the menu.

Near the bottom of the Advanced Settings menu, find the a section called Multiplayer Options.

Un-tick the checkbox “Auto Connect to Server”. This prevents the server auto connecting without the session system.

Finally, when you press the play button in your editor two clients will open.

The custom widget discussed earlier, displays the Host button and Play buttons.

On the first client I pressed the Host button. This reloaded the level.

On the second client I pressed the Play button and waited until the Find Sessions node had finished searching for multiplayer sessions.

Once this finished it auto connected me into the first clients game.

Connecting to Sessions Outside your Local Internet Network

The session created in this guide will can be used in your local network and through the internet.

If you connecting to a session in your local internet, you do not have to do anything else.

If you wish to host your session to global internet users, make sure to port forward UDP/TCP 7777. Setting up port forwarding is different per router so check your specific router instructions.

If you don’t know what port forwarding is click here.

Download the Project Files

Conclusion

Your multiplayer session is created and players can join!

This guide only brushed over the multiplayer system to start with sessions in Unreal Engine 4.

To learn more about replication and the session system, the Unreal Engine documentation as it is a good place to start.

Click here to read more about Replication.

Click here to read more about the session system nodes.

Expanding the System

To challenge yourself, try create a widget that fills itself with the results of the Find Session nodes.

This, if done correctly, will create a server browser similar to the ones found in games such as Team Fortress 2, Counter Strike and many more.

The post How to use Multiplayer Sessions in your Unreal Engine 4 game appeared first on Couch Learn.