Unreal Engine 4：学习笔记（十七）Networking & Multiplayer

逃离我推掉我的手 2022-03-21 02:14 384阅读 0赞

**目录**

一、网络模式类型

二、Client-Server模式下的使用方式

三、数据复制方式

--------------------

### 一、网络模式类型 ###

<table> 
 <tbody> 
  <tr> 
   <td style="width:156px;">NM_Standalone</td> 
   <td style="width:692px;">仅是一个可以单独运行的程序。</td> 
  </tr> 
  <tr> 
   <td style="width:156px;">NM_DedicatedServer</td> 
   <td style="width:692px;">仅是一个服务器。</td> 
  </tr> 
  <tr> 
   <td style="width:156px;">NM_ListenServer</td> 
   <td style="width:692px;">即是一个服务器，又是一个客户端。允许其它客户端远程接入。</td> 
  </tr> 
  <tr> 
   <td style="width:156px;">NM_Client&nbsp;</td> 
   <td style="width:692px;">仅是一个客户端，需要接入远端的服务器。</td> 
  </tr> 
 </tbody> 
</table>

NM\_DedicatedServer、NM\_ListenServer、NM\_Client都属于Client-Server模式。  
可通过AActor.GetNetMode( )获取。

### 二、Client-Server模式下的使用方式 ###

1.命令行启动方式

<table> 
 <tbody> 
  <tr> 
   <th colspan="1" style="width:137px;"> <p>Type</p> </th> 
   <th colspan="1"> <p>Command</p> </th> 
  </tr> 
  <tr> 
   <td colspan="1" style="width:137px;"> <p>Listen Server</p> </td> 
   <td colspan="1"> <p><code>UE4Editor.exe ProjectName MapName?Listen -game</code></p> </td> 
  </tr> 
  <tr> 
   <td colspan="1" style="width:137px;"> <p>Dedicated Server</p> </td> 
   <td colspan="1"> <p><code>UE4Editor.exe ProjectName MapName -server -game -log -port=ServerIP</code></p> </td> 
  </tr> 
  <tr> 
   <td colspan="1" style="width:137px;"> <p>Client</p> </td> 
   <td colspan="1"> <p><code>UE4Editor.exe ProjectName ServerIP -game</code></p> </td> 
  </tr> 
 </tbody> 
</table>

2.客户端接入后会依次调用如下方法  
AGameModeBase::PreLogin        可以在此判断是否要拒绝客户端连接  
AGameModeBase::Login              会创建PlayerController，并执行APlayerController::BeginPlay  
AGameModeBase::PostLogin       在此之后可以调用PlayerController上的RPC函数

3.客户端和服务端的角色

> on server:  
>     Role == ROLE\_Authority     // server  
>     RemoteRole == ROLE\_SimulatedProxy/ROLE\_AutonomousProxy    // client
> 
> on client:  
>     Role == ROLE\_SimulatedProxy/ROLE\_AutonomousProxy   // client  
>     RemoteRole == ROLE\_Authority   //  server

### 三、数据复制方式 ###

1.属性复制

属性必须定义在AActor中，属性更新频率的参数`NetUpdateFrequency，如果打开了命令行参数`net.UseAdaptiveNetUpdateFrequency，`则NetUpdateFrequency和MinNetUpdateFrequency会同时起作用。`

UPROPERTY(Replicated)
        float Health;
    
    #include "UnrealNetwork.h"
    // ...
    void AYourCharacter::GetLifetimeReplicatedProps(TArray< FLifetimeProperty > & OutLifetimeProps) const
    {
        Super::GetLifetimeReplicatedProps(OutLifetimeProps);
        DOREPLIFETIME(AYourCharacter, Health);
    }

或

UPROPERTY( ReplicatedUsing=OnRep_Health )
    float Health;
    
    UFUNCTION( )
    void OnRep_Health( );
    
    
    void MyCharacter::GetLifetimeReplicatedProps( TArray< FLifetimeProperty > & OutLifetimeProps ) const
    {   
        Super::GetLifetimeReplicatedProps( OutLifetimeProps );
        DOREPLIFETIME( MyCharacter, Health);
    }
    
    void MyCharacter::OnRep_Health( )
    {
        // Handle health changed
    }

2.Actor&Component复制

C++：

AActorComponent::SetIsReplicated(true)
    AActor::SetReplicates(true

Blueprint:  
属性面板中设置Replicates，或调用SetIsReplicated节点

3.RPC

// server to a client
    UFUNCTION( Client )
    void Function(...)
    void Function_Implementation(...)
    
    // a client to server
    UFUNCTION( Server )
    void Function(...)
    void Function_Implementation(...)
    void Function_Validate(...)
    
    // server to clients
    UFUNCTION( NetMulticast )
    void Function(...)
    void Function_Implementation(...)

参考文档

[Documentation Home -> Engine Features -> Networking and Multiplayer -> Networking Overview][Documentation Home -_ Engine Features -_ Networking and Multiplayer -_ Networking Overview]  
[Documentation Home -> Engine Features -> Networking and Multiplayer -> Multiplayer in Blueprints][Documentation Home -_ Engine Features -_ Networking and Multiplayer -_ Multiplayer in Blueprints]  
[Documentation Home -> Engine Features -> Networking and Multiplayer -> Client-Server Model][Documentation Home -_ Engine Features -_ Networking and Multiplayer -_ Client-Server Model]  
[Documentation Home -> Engine Features -> Networking and Multiplayer -> Actor Replication][Documentation Home -_ Engine Features -_ Networking and Multiplayer -_ Actor Replication]  
[Documentation Home -> Engine Features -> Networking and Multiplayer -> Actor Replication -> Property Replication][Documentation Home -_ Engine Features -_ Networking and Multiplayer -_ Actor Replication -_ Property Replication]  
[Documentation Home -> Engine Features -> Networking and Multiplayer -> Actor Replication -> RPCs][Documentation Home -_ Engine Features -_ Networking and Multiplayer -_ Actor Replication -_ RPCs]  
[Documentation Home -> Gameplay Guide -> How to Replicate Actors][Documentation Home -_ Gameplay Guide -_ How to Replicate Actors]  
[Documentation Home -> Gameplay Guide -> Replicating Variables][Documentation Home -_ Gameplay Guide -_ Replicating Variables]  
[Documentation Home -> Gameplay Guide -> Replicating Functions][Documentation Home -_ Gameplay Guide -_ Replicating Functions]  
[Documentation Home -> Gameplay Guide -> Testing Multiplayer][Documentation Home -_ Gameplay Guide -_ Testing Multiplayer]  
[Documentation Home -> Programming Guide -> Unreal Architecture -> UFunctions -> Function Specifiers][Documentation Home -_ Programming Guide -_ Unreal Architecture -_ UFunctions -_ Function Specifiers]  
[Documentation Home -> Samples and Tutorials -> Content Examples -> Networking Content Examples][Documentation Home -_ Samples and Tutorials -_ Content Examples -_ Networking Content Examples]  
[Networking/Replication][Networking_Replication]  
[Network Guide][]  
[A Crash Course in Blueprint][]

[Documentation Home -_ Engine Features -_ Networking and Multiplayer -_ Networking Overview]: https://docs.unrealengine.com/en-us/Gameplay/Networking/Overview
[Documentation Home -_ Engine Features -_ Networking and Multiplayer -_ Multiplayer in Blueprints]: https://docs.unrealengine.com/en-us/Gameplay/Networking/Blueprints
[Documentation Home -_ Engine Features -_ Networking and Multiplayer -_ Client-Server Model]: https://docs.unrealengine.com/en-us/Gameplay/Networking/Server
[Documentation Home -_ Engine Features -_ Networking and Multiplayer -_ Actor Replication]: https://docs.unrealengine.com/en-us/Gameplay/Networking/Actors
[Documentation Home -_ Engine Features -_ Networking and Multiplayer -_ Actor Replication -_ Property Replication]: https://docs.unrealengine.com/en-US/Gameplay/Networking/Actors/Properties
[Documentation Home -_ Engine Features -_ Networking and Multiplayer -_ Actor Replication -_ RPCs]: https://docs.unrealengine.com/en-US/Gameplay/Networking/Actors/RPCs
[Documentation Home -_ Gameplay Guide -_ How to Replicate Actors]: https://docs.unrealengine.com/en-US/Gameplay/HowTo/Networking/ReplicateActor
[Documentation Home -_ Gameplay Guide -_ Replicating Variables]: https://docs.unrealengine.com/en-us/Gameplay/HowTo/Networking/ReplicateVariable
[Documentation Home -_ Gameplay Guide -_ Replicating Functions]: https://docs.unrealengine.com/en-us/Gameplay/HowTo/Networking/ReplicateFunction
[Documentation Home -_ Gameplay Guide -_ Testing Multiplayer]: https://docs.unrealengine.com/en-us/Gameplay/HowTo/Networking/TestMultiplayer
[Documentation Home -_ Programming Guide -_ Unreal Architecture -_ UFunctions -_ Function Specifiers]: https://docs.unrealengine.com/latest/INT/Programming/UnrealArchitecture/Reference/Functions/Specifiers/BlueprintNativeEvent/index.html
[Documentation Home -_ Samples and Tutorials -_ Content Examples -_ Networking Content Examples]: https://docs.unrealengine.com/en-US/Resources/ContentExamples/Networking
[Networking_Replication]: https://wiki.unrealengine.com/Networking/Replication
[Network Guide]: https://wiki.unrealengine.com/4_13%2B_Network_Guide
[A Crash Course in Blueprint]: https://www.unrealengine.com/zh-CN/blog/crash-course-in-blueprints-replication