IDirectSound3DBuffer::GetVelocity
HRESULT GetVelocity(LPD3DVECTOR lpvVelocity);
Retrieves the current velocity for this sound buffer.
·Returns DS_OK if successful, or DSERR_INVALIDPARAM otherwise.
lpvVelocity
Address of a D3DVECTOR structure that will contain the sound buffer's current velocity.
Velocity is used for Doppler effects only. It does not actually move the buffer. For additional information, see Position and Velocity.