UTIL_VecToYaw()
Is an utility function used to determine a Yaw value from a Vector. It is defined in ..\game\shared\util_shared.cpp
It does an atan2( y, x ) on the components of the Vector passed in parameter, converts it in degrees and ensure it's between 0-360 degrees ( and not between 180 to -180 ).
Declaration
Declared in ..\game\shared\util_shared.h
//-----------------------------------------------------------------------------
// Pitch + yaw
//-----------------------------------------------------------------------------
float UTIL_VecToYaw (const Vector &vec);