RadeonRays
Engine/Binaries/ThirdParty/Phonon/Win64/RadeonRays.dll
This allows Steam Audio to perform an optimized ray tracing algorithm which determines the acoustic response of a given space. This is a dll which is linked against when using SteamAudio
https://raw.githubusercontent.com/GPUOpen-LibrariesAndSDKs/RadeonRays_SDK/master/LICENSE.txt
Licensees
Git
P4
\UE4\Engine\Source\ThirdParty\Licenses\RadeonRaysSDK_License.txt