[jlalt]

You can use this function:
https://sampwiki.blast.hk/wiki/InterpolateCameraPos

or this two:
https://sampwiki.blast.hk/wiki/SetPlayerCameraPos
https://sampwiki.blast.hk/wiki/SetPlayerCameraLookAt

and for back it use this:
https://sampwiki.blast.hk/wiki/SetCameraBehindPlayer