UE-自带的HotUpdate【转】

原文链接：https://baijiahao.baidu.com/s?id=1745200406976270792&wfr=spider&for=pc

这是百度可以直接搜索到的

UE4官网针对热更新有较为详细的步骤，但是其中漏掉的几个问题导致实现不了效果。

总的来说可以分为四大步。

第一步：自己的项目设置好插件ChunkDownloader

1.新建第三人称c++项目工程，设置分块打包

2.勾选插件ChunkDownloader

3.修改项目的 Build.cs 文件

PrivateDependencyModuleNames.AddRange(

new string[]{    "ChunkDownloader"}

4.保存后重新生成项目文件。操作：右键点击你的 .uproject 文件，然后点击 生成项目文件（Generate Project Files）。

第二步：资源分块，然后打包。为了测试方便，新建三个map，分别放在不同的文件夹。我的是Test，Test2，Test3.

1. 添加资源分块标签。

 

标签设置如图：红框内需必备

属性解释：

依次对自己的测试资源添加标签。

2.打包默认设置即可。这样你可以在打出的包里看到分好的pak文件。红框ID与你的标签ID对应。

第三步：构建资源清单与托管本地测试服务器

1.构建资源清单。这里注意，英文字符下 TAB建进行属性空格。

我的清单如下：

 

资源文件夹结构，其中Windows文件夹中放的是分块后的pak文件

稍作解释：

第1行是需要下载更新的pak数目

第2行理解为资源和清单所在的文件夹

后面的几行就是pak资源相关的。共5个属性。资源名字，资源大小（右键资源看其属性字节数），版本号，ChunkID，资源所在位置。

2.文件托管到本地测试服务器

如何创建本地测试服务器这里不啰嗦，可以参考ue4官网。

但是这里要注意：新建文件夹PatchingDemoCDN，除了上传我们前面准备好的资源和清单即PatchingDemoKey文件夹。我们还需要在PatchingDemoCDN文件夹中新建表单

这个表单中我们要写上$BUILD_ID对应的也就是资源和清单所在的文件夹PatchingDemoKey

最后我们还需要在项目的配置表DefaultGame.ini中添加用来下载资源的网站地址。这里我们是用本地服务器测试的。

[/Script/Plugins.ChunkDownloader PatchingDemoLive]

+CdnBaseUrls=127.0.0.1/PatchingDemoCDN

第三步：编辑代码和逻辑。（开始不必扩展，实现基本功能即可）

1.GameInstance不仅具有可以绑定的相应初始化和关闭函数，而且还可以在游戏运行时持续访问ChunkDownloader。

所以使用 GameInstance 作为基类创建 新C++类。将其命名为 PatchingDemoGameInstance。

最后代码为：

// Fill out your copyright notice in the Description page of Project Settings.
 
#pragma once
 
#include "CoreMinimal.h"
 
#include "Engine/GameInstance.h"
 
#include "PatchingDemoGameInstance.generated.h"
 
/**
 
*
 
*/
 
DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FPatchCompleteDelegate, bool, Succeeded);
 
UCLASS()
 
class UPatchingDemoGameInstance : public UGameInstance
 
{
 
GENERATED_BODY()
 
public:
 
/** Overrides */
 
virtual void Init() override;
 
virtual void Shutdown() override;
 
/** Delegates */
 
/** Fired when the patching process succeeds or fails */
 
UPROPERTY(BlueprintAssignable, Category = "Patching")
 
FPatchCompleteDelegate OnPatchComplete;
 
/** Starts the game patching process. Returns false if the patching manifest is not up to date. */
 
UFUNCTION(BlueprintCallable, Category = "Patching")
 
bool PatchGame();
 
UFUNCTION(BlueprintPure, Category = "Patching|Stats")
 
void GetLoadingProgress(int32& FilesDownloaded, int32& TotalFilesToDownload, float& DownloadPercent, int32& ChunksMounted, int32& TotalChunksToMount, float& MountPercent) const;
 
protected:
 
//Tracks Whether or not our local manifest file is up to date with the one hosted on our website
 
bool bIsDownloadManifestUpToDate;
 
void OnManifestUpdateComplete(bool bSuccess);
 
/** List of Chunk IDs to try and download */
 
UPROPERTY(EditDefaultsOnly, Category = "Patching")
 
TArray<int32> ChunkDownloadList;
 
/** Called when the chunk download process finishes */
 
void OnDownloadComplete(bool bSuccess);
 
/** Called whenever ChunkDownloader's loading mode is finished*/
 
void OnLoadingModeComplete(bool bSuccess);
 
/** Called when ChunkDownloader finishes mounting chunks */
 
void OnMountComplete(bool bSuccess);
 
};

.cpp
 
// Fill out your copyright notice in the Description page of Project Settings.
 
#include "PatchingDemoGameInstance.h"
 
#include "ChunkDownloader.h"
 
#include "Misc/CoreDelegates.h"
 
#include "AssetRegistryModule.h"
 
void UPatchingDemoGameInstance::Init()
 
{
 
Super::Init();
 
const FString DeploymentName = "PatchingDemoLive";
 
const FString ContentBuildId = "PatchingDemoKey";
 
// initialize the chunk downloader
 
TSharedRef<FChunkDownloader> Downloader = FChunkDownloader::GetOrCreate();
 
// TODO 安卓下载方式
 
// Downloader->Initialize("Android", 8);
 
Downloader->Initialize("Windows", 8);
 
// load the cached build ID
 
Downloader->LoadCachedBuild(DeploymentName);
 
// update the build manifest file
 
TFunction<void(bool bSuccess)> UpdateCompleteCallback = [&](bool bSuccess){bIsDownloadManifestUpToDate = true;};
 
Downloader->UpdateBuild(DeploymentName, ContentBuildId, UpdateCompleteCallback);
 
}
 
void UPatchingDemoGameInstance::Shutdown()
 
{
 
Super::Shutdown();
 
// Shut down ChunkDownloader
 
FChunkDownloader::Shutdown();
 
}
 
void UPatchingDemoGameInstance::OnManifestUpdateComplete(bool bSuccess)
 
{
 
bIsDownloadManifestUpToDate = bSuccess;
 
}
 
void UPatchingDemoGameInstance::GetLoadingProgress(int32& BytesDownloaded, int32& TotalBytesToDownload, float& DownloadPercent, int32& ChunksMounted, int32& TotalChunksToMount, float& MountPercent) const
 
{
 
//Get a reference to ChunkDownloader
 
TSharedRef<FChunkDownloader> Downloader = FChunkDownloader::GetChecked();
 
//Get the loading stats struct
 
FChunkDownloader::FStats LoadingStats = Downloader->GetLoadingStats();
 
//Get the bytes downloaded and bytes to download
 
BytesDownloaded = LoadingStats.BytesDownloaded;
 
TotalBytesToDownload = LoadingStats.TotalBytesToDownload;
 
//Get the number of chunks mounted and chunks to download
 
ChunksMounted = LoadingStats.ChunksMounted;
 
TotalChunksToMount = LoadingStats.TotalChunksToMount;
 
//Calculate the download and mount percent using the above stats
 
DownloadPercent = ((float)BytesDownloaded / (float)TotalBytesToDownload)*100.0f;
 
MountPercent = ((float)ChunksMounted / (float)TotalChunksToMount)*100.0f;
 
}
 
void UPatchingDemoGameInstance::OnLoadingModeComplete(bool bSuccess)
 
{
 
OnDownloadComplete(bSuccess);
 
}
 
void UPatchingDemoGameInstance::OnMountComplete(bool bSuccess)
 
{
 
OnPatchComplete.Broadcast(bSuccess);
 
}
 
bool UPatchingDemoGameInstance::PatchGame()
 
{
 
// make sure the download manifest is up to date
 
if (bIsDownloadManifestUpToDate)
 
{
 
// get the chunk downloader
 
TSharedRef<FChunkDownloader> Downloader = FChunkDownloader::GetChecked();
 
// report current chunk status
 
for (int32 ChunkID : ChunkDownloadList)
 
{
 
int32 ChunkStatus = static_cast<int32>(Downloader->GetChunkStatus(ChunkID));
 
UE_LOG(LogTemp, Display, TEXT("Chunk %i status: %i"), ChunkID, ChunkStatus);
 
}
 
TFunction<void(bool bSuccess)> DownloadCompleteCallback = [&](bool bSuccess) {OnDownloadComplete(bSuccess); };
 
Downloader->DownloadChunks(ChunkDownloadList, DownloadCompleteCallback, 1);
 
// start loading mode
 
TFunction<void(bool bSuccess)> LoadingModeCompleteCallback = [&](bool bSuccess) {OnLoadingModeComplete(bSuccess); };
 
Downloader->BeginLoadingMode(LoadingModeCompleteCallback);
 
return true;
 
}
 
// we couldn't contact the server to validate our manifest, so we can't patch
 
UE_LOG(LogTemp, Display, TEXT("Manifest Update Failed. Can't patch the game"));
 
return false;
 
}
 
void UPatchingDemoGameInstance::OnDownloadComplete(bool bSuccess)
 
{
 
if (bSuccess)
 
{
 
UE_LOG(LogTemp, Display, TEXT("Download complete"));
 
// get the chunk downloader
 
TSharedRef<FChunkDownloader> Downloader = FChunkDownloader::GetChecked();
 
FJsonSerializableArrayInt DownloadedChunks;
 
for (int32 ChunkID : ChunkDownloadList)
 
{
 
DownloadedChunks.Add(ChunkID);
 
}
 
//Mount the chunks
 
TFunction<void(bool bSuccess)> MountCompleteCallback = [&](bool bSuccess) {OnMountComplete(bSuccess); };
 
Downloader->MountChunks(DownloadedChunks, MountCompleteCallback);
 
OnPatchComplete.Broadcast(true);
 
}
 
else
 
{
 
UE_LOG(LogTemp, Display, TEXT("Load process failed"));
 
// call the delegate
 
OnPatchComplete.Broadcast(false);
 
}
 
}

2.使用 PatchingDemoGameInstance 作为基类创建 新蓝图，命名为 CDGameInstance

3.打开CDGameInstance，添加chunk列表

4.创建名为 PatchingGameMode 的新游戏模式 蓝图

5.项目做如下设置。

6.第三人称游戏map设置gamemode为PatchingGameMode

7.打开PatchingGameMode，添加如下蓝图逻辑。

beginPlay后添加：patchGame返回值为true则进入tick即开始下载资源。否则根据资源数进行进一步检测。

tick后添加：大概意思就是资源下载并且装载完打开Test3地图。

到此代码，逻辑都写好了。

第四步：打包测试

1.直接打包。

结果是包文件夹里的Content中的paks文件夹有四个pak文件。删掉ID为1001-1003的pak。

2.运行.exe

结果如下：

下载中

下载完成，3秒后进入Test3地图。

下载的文件：