---
title: UnrealEngine的命令行操作方式
date: 2023-04-27 11:15:14
excerpt: 
tags: CommandLet
rating: ⭐
---
# 前言
最近想实现使用UnrealEditor-Cmd进行资产处理并且渲染的功能，这里简单归纳一下。

# 命令行启动方式
## CommandLet
继承UCommandLet，重写Run()相关逻辑写在里面即可。启动参数大致如下：
```bash
UnrealEditor-Cmd.exe ProjectPath -run=CommandletName
```

这里很推荐去看一下`UImportAssetsCommandlet`，里面实现了使用Json传参的方法。

### 变相执行ConsoleCommand
创建一个CommandLet并且接收参数，并在最后下列代码即可。
```c++
GEditor->Exec(World, TEXT("MAP REBUILD ALLDIRTYFORLIGHTING"));
```

## Python
- 官方文档：https://docs.unrealengine.com/4.27/en-US/ProductionPipelines/ScriptingAndAutomation/Python/
```bash
UnrealEditor-Cmd.exe ProjectPath -ExecutePythonScript="c:\my_script.py"
```

还存在另一种方法，编辑器启动时环境最小，不包含UI或渲染。该方法执行起来非常快，但是加载脚本需要交互的关卡和其他种类资源时比较棘手。在命令行中添加以下参数：-`run=pythonscript -script=<script_file>`比如：
```bash 
UnrealEditor-Cmd.exe -run=pythonscript -script="c:\\my_script.py"
```

## AutomationTest
一个另类的思路就是使用自动测试工具。通过`IMPLEMENT_COMPLEX_AUTOMATION_TEST`实现一个自动测试类之后实现`RunTest`即可。启动参数：
```bash
UnrealEditor-Cmd.exe ProjectPath -AutomationTestName -Execcmds="Command-Line Arguments"
```

大致过程可以参考视频：https://www.youtube.com/watch?v=kJd5-jY46Gk
视频中的启动参数：
```python
import subprocess

engine = "C:/work/Epic/UE_5.0/Engine/Binaries/win64/UnrealEditor.exe"
project = "C:/Work/Prototypes/CompileBlueprintProj/CompileBlueprintProj.uproject"
log_location = "C:/Work/Prototypes/CompileBlueprintProj/blueprint_results.log"

cmd =[
engine,project,
f"-abslog={flog_location}",
"-editortest",
"-Execcmds= "Automation SetFilter Stress, Automation list，Automation RunTest Project.Blueprints.compile Blueprints\"","-testexit=\ "Automation Test Queue Empty\"",
cmd = " ".join(cmd)
subprocess.run(cmd)
```

引擎内的FCompileBlueprintsTest具体代码：
```c++
IMPLEMENT_COMPLEX_AUTOMATION_TEST(FCompileBlueprintsTest, "Project.Blueprints.Compile Blueprints", EAutomationTestFlags::EditorContext | EAutomationTestFlags::StressFilter)

/************************************************************************/  
/* FCompileBlueprintsTest                                              */  
/************************************************************************/  
  
/** Requests a enumeration of all blueprints to be loaded */  
void FCompileBlueprintsTest::GetTests(TArray<FString>& OutBeautifiedNames, TArray <FString>& OutTestCommands) const  
{  
   FBlueprintAutomationTestUtilities::CollectTestsByClass(UBlueprint::StaticClass(), OutBeautifiedNames, OutTestCommands, /*bool bIgnoreLoaded =*/false);  
}  
  
  
bool FCompileBlueprintsTest::RunTest(const FString& Parameters)  
{  
   UE_LOG(LogBlueprintAutomationTests, Log, TEXT("Beginning compile test for %s"), *Parameters);  
   return FBlueprintAutomationTestUtilities::CompileBlueprint(Parameters);  
}

/**  
 * Simulates the user pressing the blueprint's compile button (will load the * blueprint first if it isn't already). ** @param  BlueprintAssetPath  The asset object path that you wish to compile. * @return False if we failed to load the blueprint, true otherwise 
 */
static bool CompileBlueprint(const FString& BlueprintAssetPath)  
{  
	UBlueprint* BlueprintObj = Cast<UBlueprint>(StaticLoadObject(UBlueprint::StaticClass(), NULL, *BlueprintAssetPath));  
	if (!BlueprintObj || !BlueprintObj->ParentClass)  
	{      
		UE_LOG(LogBlueprintAutomationTests, Error, TEXT("Failed to compile invalid blueprint, or blueprint parent no longer exists."));  
		return false;  
	}  
	UPackage* const BlueprintPackage = BlueprintObj->GetOutermost();  
	// compiling the blueprint will inherently dirty the package, but if there   
	// weren't any changes to save before, there shouldn't be after  
	bool const bStartedWithUnsavedChanges = (BlueprintPackage != nullptr) ? BlueprintPackage->IsDirty() : true;  
	
	FKismetEditorUtilities::CompileBlueprint(BlueprintObj, EBlueprintCompileOptions::SkipGarbageCollection);  
	
	if (BlueprintPackage != nullptr)  
	{      
	   BlueprintPackage->SetDirtyFlag(bStartedWithUnsavedChanges);  
	}  
	return true;  
}
```

# 编辑器内调用
## Python
- 官方文档：https://docs.unrealengine.com/4.27/en-US/ProductionPipelines/ScriptingAndAutomation/Python/
将OutputLog的ConsoleCommand的类型从CMD=>Python，之后输入Python命令即可。

## CustomConsoleCommand
除了UFUNCTION中指定Exec之外（因为这个只能在部分类中实现并不通用）就是使用`IConsoleManager::Get().RegisterConsoleCommand()`，卸载函数为`IConsoleManager::Get().UnregisterConsoleObject()`，一般会在Module的StartupModule()/ShutdownModule()或者Subsystem的对应函数中进行注册/卸载。用法如下：
```c++
IConsoleManager::Get().RegisterConsoleCommand(  
TEXT("ConsoleCommandName"),  
TEXT("Useage Info"),  
FConsoleCommandDelegate::CreateStatic(&UYourClass::Function),  
ECVF_Default);
```

相关的FConsoleCommandDelegate委托都位于IConsoleManager.h，根据需求选择。

# 其他
## CommandLet Server
```c++
int32 FEditorDomainSaveServer::Run()
{
	if (!TryInitialize())
	{
		Shutdown();
		return 1;
	}

	while (PollShouldRun())
	{
		bool bIsIdle = true;
		TickPendingPackages(bIsIdle);
		PollIncomingConnections(bIsIdle);
		PollConnections(bIsIdle);
		TickMaintenance(bIsIdle);
	}

	Shutdown();
	return 0;
}

void FEditorDomainSaveServer::TickMaintenance(bool bIsIdle)  
{  
	using namespace UE::EditorDomainSave;  
  
	SetIdle(bIsIdle);  
	double CurrentTime = FPlatformTime::Seconds();  
	if (bIsIdle)  
	{  
		if (!HasExpectedConnections() && CurrentTime - IdleStartTime > Constants::ServerAbdicationCooldownSeconds)  
		{  
			if (TryAbdicate())  
			{  
				return;  
			}  
		}  
	}  
  
	double CollectGarbageCooldownSeconds = bIsIdle ?  
	Constants::CollectGarbageIdleCooldownSeconds :  
	Constants::CollectGarbageActiveCooldownSeconds;  
	bool bCollectedGarbageAfterIdle = bIsIdle && LastGarbageTime >= IdleStartTime;  
	if (!bCollectedGarbageAfterIdle && CurrentTime - LastGarbageTime > CollectGarbageCooldownSeconds)  
	{  
		CollectGarbage(RF_NoFlags);  
		LastGarbageTime = FPlatformTime::Seconds();  
	}  
	  
	if (bIsIdle)  
	{  
		FPlatformProcess::Sleep(Constants::ServerIdleSleepPeriodSeconds);  
	}  
}
```

## 日志写入文件
```bash
f"-abslog={log_location}"
```