How to make game window transparent using opacity from camera

[t-hoshino]

You can access HWND from the engine’s global variable GEngine.

#include "Widgets/SWindow.h"
#include "Engine/Engine.h"


    if (GEngine && GEngine->GameViewport && GEngine->GameViewport->GetWindow().IsValid())
    {
        TSharedPtr<SWindow> GameSWindow = GEngine->GameViewport->GetWindow();
        if (GameSWindow.IsValid() && GameSWindow->GetNativeWindow().IsValid())
        {
            void* Handle = GameSWindow->GetNativeWindow()->GetOSWindowHandle();
            HWND hwnd = static_cast<HWND>(Handle);
        }
    }