| Parameter | Description |
|---|---|
| forward | The view forward direction. |
| up | The view up direction. |
quaternion The quaternion view rotation or the identity quaternion.
Returns a quaternion view rotation given a forward vector and an up vector. The two input vectors are not assumed to be unit length. If the magnitude of either of the vectors is so extreme that the calculation cannot be carried out reliably or the vectors are collinear, the identity will be returned instead.