static TAutoConsoleVariable<int32> CVarPSOPrecacheAlphaColorChannel(
	TEXT("r.PSOPrecache.PrecacheAlphaColorChannel"),
	1,
	TEXT("Also Precache PSOs with scene color alpha channel enabled. Planar reflections and scene captures use this for compositing into a different scene later."),
	ECVF_ReadOnly
);

// Scene color alpha is used during scene captures and planar reflections.  1 indicates background should be shown, 0 indicates foreground is fully present.

file
class        class FBasePassMeshProcessor : public FSceneRenderingAllocatorObject<FBasePassMeshProcessor>, public FMeshPassProcessor
function     static void AddBasePassGraphicsPipelineStateInitializer

		// Planar reflections and scene captures use scene color alpha to keep track of where content has been rendered, for compositing into a different scene later
		static TConsoleVariableData<int32>* CVar = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.PSOPrecache.PrecacheAlphaColorChannel"));
		if (bPrecacheAlphaColorChannel && CVar && CVar->GetValueOnAnyThread() > 0)
		{
			FGraphicsPipelineRenderTargetsInfo AlphaColorRenderTargetsInfo = RenderTargetsInfo;

			bool bRequiresAlphaChannel = true;
			ETextureCreateFlags ExtraSceneColorCreateFlags = ETextureCreateFlags::None;