| DirectX SDK | 
The DirectX7.QuaternionMultiply method calculates the product of two quaternion types.
object.QuaternionMultiply(quat As D3DRMQUATERNION, _
    quatA As D3DRMQUATERNION, _
    quatB As D3DRMQUATERNION)
If the method fails, an error is raised and Err.Number is set.