Why receiving textures done with CPU copying?

[microdee]

I'm talking about this line:

Spout-UE4/Source/SpoutPlugin/Private/SpoutBPFunctionLibrary.cpp

Line 584 in 8740fc1

RHIUpdateTexture2D(Params->Texture2DResource->GetTexture2DRHI(), 0, *Params->UpdateRegions, mapped.RowPitch, (uint8*)pixel);

and

Spout-UE4/Source/SpoutPlugin/Private/SpoutBPFunctionLibrary.cpp

Line 573 in 8740fc1

HRESULT hr = g_pImmediateContext->Map(t_texTemp, 0, D3D11_MAP_READ, 0, &mapped);

and

Spout-UE4/Source/SpoutPlugin/Private/SpoutBPFunctionLibrary.cpp

Line 236 in 8740fc1

description.CPUAccessFlags = D3D11_CPU_ACCESS_READ | D3D11_CPU_ACCESS_WRITE;

Doing this defeats the purpose of Spout in the first place. Is there any reason why not just copy resource like this:?

ID3D11Texture2D* t_dst = (ID3D11Texture2D*)SenderStruct->Texture2DResource->GetTexture2DRHI()->GetNativeResource();
g_pImmediateContext->CopyResource(t_dst, t_texTemp);

and then call it a day? I'm not sure if texTemp is even necessary anymore if we don't do staging and CPU access.