GetCopyableFootprints

void GetCopyableFootprints(
    const D3D12_RESOURCE_DESC  pResourceDesc,
    UINT FirstSubresource,
    UINT NumSubresources,
    UINT64 BaseOffset,
    D3D12_PLACED_SUBRESOURCE_FOOTPRINT  pLayouts,
    UINT  pNumRows,
    UINT64  pRowSizeInBytes,
    UINT64  pTotalBytes
)

// Returns required size of a buffer to be used for data upload
inline UINT64 GetRequiredIntermediateSize(
_In_ ID3D12Resource* pDestinationResource,
_In_range_(0,D3D12_REQ_SUBRESOURCES) UINT FirstSubresource,
_In_range_(0,D3D12_REQ_SUBRESOURCES-FirstSubresource) UINT NumSubresources)
{
D3D12_RESOURCE_DESC Desc = pDestinationResource->GetDesc();
UINT64 RequiredSize = 0;

ID3D12Device* pDevice;
pDestinationResource->GetDevice(__uuidof(*pDevice), reinterpret_cast<void**>(&pDevice));
pDevice->GetCopyableFootprints(&Desc, FirstSubresource, NumSubresources, 0, nullptr, nullptr, nullptr, &RequiredSize);
pDevice->Release();

return RequiredSize;
}