Over the past several months, Nintendo has revealed much of its thinking behind Wii U, including how it originally approached development of the system. Within these origin stories have been demonstrations of early Wii U GamePad prototypes, or more specifically what some teams - like the Miiverse team - crafted to crudely test dual-screen layouts. In that case, the GamePad was a cardboard cutout, with pen and paper being used to simulate a LCD screen.

In a new Iwata Asks column, however, the Nintendo Land development team revealed the true origins of the Wii U GamePad, before the console itself even existed.

The first test involved including a screen as part of an experiment with the Wii Zapper accessory. Check it out:

This eventually became an entire console.

This prototype was so well-received that Shigeru Miyamoto himself forced a gyroscope to be added to the Nintendo 3DS, which by that point had its hardware finalized. But this simple Zapper test then evolved to become an early concept for a new controller for a new system.

The earliest form of Wii U's GamePad.

As is customary at Nintendo, this basic tech, which was effectively two Wii remotes duct-taped to an LCD monitor, became the starting point for over 30 game demos. Two Wiis working together were used as a simulation for Wii U's actual computing power, and many of the ideas that Nintendo came up with eventually made their way into Nintendo Land, what is arguably Nintendo's best demonstration of Wii U's potential. Considering its close origins with the controller's development, it's easy to see why.

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