UE4 uses these API's?

Does UE4 uses Microsoft’s DirectCompute ,CUDA,OpenCl,Compute Shaders in OpenGL? - DirectCompute - Wikipedia
If yes,then where they are used?
If no,then where they are used(just curious) ?

Try doing some searches in the UnrealEngine github repo. I don’t know if DirectCompute, CUDA, or OpenCL are used, but I do see quite a bit of OpenGL in /Engine/Source/Runtime/OpenGLDrv. Check the /Engine/Source/Runtime folder and search through there.

Well UE4 got OpenGL renderer which is used on Linux and OS X (and you can even use it in Windows if you want by starting editor with -opengl or -opengl4 options), so it’s kind of obviues it’s there ;p

When i browse source i see lot of PhysX refrences in terms of GPU computing, not sure about other once. Try searching libarary calls in github :stuck_out_tongue: Unreal is made seemless, trying to connect lot of platfrom APIs to common interface, so you don’t need to worry what it uses and most importently what UE4 will use in future