A (not so) minimal project template that shows how to use and launch a DarkRift2 client and server in a single Unity-Editor. I also added some build scripts and debugging tools that further improve the developer experience and boost productivity.
The project is intended as a template for 3D multiplayer games with Unity and DarkRift2 with the aim for a maximum in productivity and comfort when it comes to developing multiplayer games. Managing server and client builds can often be a pain in the a** and not beeing able to run the server and the client in the same project slows down your development a lot and can be extremly frustrating.
Some of the code and the bascic principals behind this template where taken form this awesome tutorial https://github.com/LukeStampfli/EmbeddedFPSExample which is a really great learning resource for DarkRift2 and multiplayer games in general. The biggest differnce to this tutorial is, that this project is only using a single server instead of a server that has multiple rooms which the client can connect to.
- Server that manages player connections and logins
- Client that is able to login and "play"
- Multiplayer first person character controller (Walk, Look, Jump, Run)
- Server authoritive movement with client side prediction and reconciliation
- (Raycast-)Shooting with lag compensation
- Buildscripts (currently only for Windows) that easily let you build and run the server or the client
- Command line arguments that allow the client to automatically login with a given username
SinglePlayerServer, a component that lets you run server and client simultaneously in the Unity-EditorDebugUtility, a component that provides a ingame log, a console where you can type commands and the possibility to display values as graph
I used some assets from the Unity Asset Store for this project which are not included in the project and need to be installed manually after you checked out the project:
- DarkRift2 (https://assetstore.unity.com/packages/tools/network/darkrift-networking-2-95309)
- FreeFlyCam (https://assetstore.unity.com/packages/tools/camera/free-fly-camera-140739)
- DebugGUI Graph (https://assetstore.unity.com/packages/tools/gui/debuggui-graph-139275)
FreeFlyCam is not mandatory and is only used by the camera of the server. If you don't want to download or use it, just remove the script from the camera GameObject in the "Server" scene.
DebugGUI is also not mandatory, but is a very usefull debug tool I use to display the FPS and the latency. If you want to use the DebugUtility you need to get this asset.
The projects layout is pretty minimalistic and should be self explanatory. There are three scenes "Login", "Client" and "Server". The "Login" scene is the entrypoint for the client and switches automatically to the "Client" scene after a successfull login. The "Server" scene is the entrypoint of the server project. If in need for a desciption of some of the components in the scenes or in general, please visit the above mentioned tutorial as it provides a great explanation of everything going on.
In the file Assets/Scripts/Editor/Builds.cs you can find a variety of build scripts which allow you to build and/or run the client or server via a "Builds" menu item in the editor, without the need for the build screen of unity. Currently all those scripts target the windows plattform but it is very easy to change this to run it on your desired plattform. Also the builds have currently no BuildOptions, which also can be very helpfull for development.
When running the client via this menu option, the buildscript passes a randomly generated username to the client via command line. The client then parses this name and automatically logs you in with this username so you don't have to type a name and press the login button every time you launch a client.
The SinglePlayerServer which can be added the "Server" scene, is the component which allows you to run the server and the client simultaneously in the same editor. But in fact it is actually not this component that does the magic, instead multiple pieces across the project the enable it. The ServerInstance component is creating its own physics scene which hosts its environment and all the players. So when you start a client in parallel to the server, the actors from both scenes don't interfere with each other as they are just visually in the same scene but not physically. When enabled the SinglePlayerServer component then handles the launch of the login and then automatically sets a username and logs you in and afterwards switches to the client scene and et voila, you got a server and a client running at the same time in the unity editor. Currently there is a small downside to this when running client and server in parallel, the camera of the client renders both scenes which looks a bit weird as the player is not always at the same postion for the server and the client. More about this in the ToDo section.
When starting the standalone game with the command line argument "-debugUtil" or by dragging the DebugUtility into your scene, you enable them. When pressing "Ctrl + C" you can toggle the debug console. When the console is enabled, the inputs for server and client are disabled. The console provides a full log and when you click on a log entry, you get a popup which dispalys the stacktrace of this message. At the bottom of the log there is a export button which exports the entire log into a "debug" folder at the location of the executable. Under the log there is a samll input, where you can enter commands that then get executed. In the folder /Scripts/Utility/Debugging/Console/Commands/ are three files in ehich the commands are defined. There are command that only get loaded when running a server or client and on file that contains commands that are loaded for both. One of the commands that are added in both is the debug-graphs command, that toggles a small display on the top right corner that displays a small graph containing the FPS, smoothed out FPS and for the Client it also displays the latency to the server.
As already mentioned above, some of the code is taken from here https://github.com/LukeStampfli/EmbeddedFPSExample, but the tutorial is not completly finished in this repository. The last part of the tutorial, shooting with lag compensation, isn't completly implemented. The shooting is there but there is no health system and related stuff like dying and respawning. Maybe add a nice map and some sound to howe to implement stuff like this in an online game.
Feel free to use this template to start a new project or use it as a learning resource for DarkRift2, using build scripts in Unity or muliplayer games in general.
One thing that bothers me and I want to change for sure is, that when using the SingePlayerServer the camera of the player renders both, the clients scene and the server scene. For the sake of this demo project I could have just set the layers of every object on the server scene to a specific layer and then set the clients camera to not render this layer. This approach isn't suitable for bigger projects as you may want to use layers for other stuff and you would need some complex logic for setting this layers, as some of the assets are used for both projects, the server and the client. I haven't found a good way yet to solve this and if someone has a good idea please contact me or create an issue.
As of now, I consider this project finished but I may pick it up at some point and add some of the stuff that I implement for the games which I started with this template which may be:
- Third person mode
- Advanced character controller with climbing and vaulting