小笔记 - Houdini to Unreal

1, Houdini rotation to UE4 rotation?

https://www.sidefx.com/forum/topic/69197/?page=1#post-294295

 

HQuat (X,Y,Z,W) = UEQuat( -X, -Z, -Y, W)
and the other way around is
UEQuat (X,Y,Z,W) = HQuat (X, Z, Y, -W)