[UE4] 使用 GUI 框架“Dear ImGui” 示例：ImguiLogWindow

Posted 2022-03-15 u010019717

 

要想从引擎那得到日志数据可以继承自  public FOutputDevice  。

其中一个重要的虚方法

virtual void Serialize(const TCHAR* V, ELogVerbosity::Type Verbosity, const class FName& Category) override;

#pragma once

#include "ImguiConsole.h"
#include "Subsystems/GameInstanceSubsystem.h"
#include "Misc/OutputDevice.h"
#include "UImguiLogSubsystem.generated.h"

#ifdef __clang__
#pragma clang diagnostic ignored "-Woverloaded-virtual"
#pragma clang diagnostic ignored "-Wformat-security"
#endif

UCLASS()
class MYDEMO_API UImguiLogSubsystem : public UGameInstanceSubsystem, public FOutputDevice

	GENERATED_BODY()
public:
	virtual void Initialize(FSubsystemCollectionBase& Collection) override;
	virtual void Deinitialize() override;

	virtual void Serialize(const TCHAR* V, ELogVerbosity::Type Verbosity, const class FName& Category) override;

	void Draw(bool* bIsOpen);

protected:

	
	FAppConsole Console;
;

#include "ImguiLogSubsystem.h"

void UImguiLogSubsystem::Initialize(FSubsystemCollectionBase& Collection)

	check(GLog);
	GLog->AddOutputDevice(this);
	Console.InitImgui();


void UImguiLogSubsystem::Deinitialize()

	GLog->RemoveOutputDevice(this);


void UImguiLogSubsystem::Draw(bool* bIsOpen)

	Console.Draw("Console", bIsOpen);


void UImguiLogSubsystem::Serialize(const TCHAR* Message, ELogVerbosity::Type Verbosity, const class FName& Category)

	Console.AddLog(Verbosity, TCHAR_TO_ANSI(*Category.ToString()), TCHAR_TO_ANSI(Message));

直接在之前的Tick 方法中驱动LogWindow 的绘制。 

void AImGuiTest::ShowLogWindow()

    if (ImGui::BeginMainMenuBar())
    
        if (ImGui::BeginMenu("Window"))
        
            if (ImGui::MenuItem("Log"))
            
                bShowLogWindow = !bShowLogWindow;
            
            ImGui::EndMenu();
        
        ImGui::EndMainMenuBar();
    

    if (bShowLogWindow)
    
        UImguiLogSubsystem* Logger = GetGameInstance()->GetSubsystem<UImguiLogSubsystem>();
        Logger->Draw(&bShowLogWindow);
    


void AImGuiTest::Tick(float DeltaTime)

   Super::Tick(DeltaTime);
#if WITH_IMGUI
   ImGui::Begin("ImGui Debug Order Test");
   ImGui::Text("Actor Tick: Actor = '%ls', World = '%ls', CurrentWorld = '%ls'", *GetNameSafe(this), *GetNameSafe(GetWorld()), *GetNameSafe(GWorld));
    const FImGuiTextureHandle TextureHandle = FImGuiModule::Get().FindTextureHandle( FName(Texture->GetName()) ); 
    ImGui::Image(TextureHandle, ImVec2( 200 , 200 ));    
   ImGui::End();
   
   ShowLogWindow();
    
    if (ImGui::TreeNode("Basic"))
    
        static int clicked = 0;
        if (ImGui::Button("Button"))
            clicked++;
        if (clicked & 1)
        
            ImGui::SameLine();
            ImGui::Text("Thanks for clicking me!");