This message is generated when the value of the ViewPoint option falls inside of the bounding box in scaled coordinates.
In the scaled coordinates used for the ViewPoint option, the magnitude of at least one of the numbers in the value of the option must be greater than 0.5 for the point to be outside of the bounding box.
Off[message] switches off the message; On[message] switches it on. For example: Off[ViewPoint::viewp].