The Wii U controller contains the same motion tracking hardware as a Nintendo Wiimote, which means the system can track its relative position at all times, and update the controller screen depending on its orientation.

FORBES: Hands On With The Nintendo Wii U

Designed and built with both casual and serious FPS gaming in mind, the MAG II features 3 pre-programmed sensitivity options and is the only gun controller to incorporate Motion Sensing and Gyroscopic Induction movement tracking.

ENGADGET: MAG II Gun Controller reports for FPS duty on PS3 and PC from Nov 20th

The setup uses a splittable controller and a processing unit to enable seamless motion control and spacial tracking on any title and system.

ENGADGET