Create a "Gamepad Mode" UI

[DavidJCobb]

One of my pipe dreams for this mod was a gamepad-oriented UI that used the native gamepad assets. This proved to be impractical for two main reasons: the systems Zenimax used to process gamepad input rely on protected functions and don't use CallSecureProtected, so any attempt to use their singletons throws an exception; and their various templates and widgets are... complicated.

During development, I created a prototype system for capturing and dispatching gamepad input; the design was inspired by TES4 Oblivion's keyboard-navigation system, which I reverse-engineered a year or so ago. The system relies on an action layer for intercepting buttons, and a frame handler for intercepting joystick movement. The system worked well enough for allowing me to navigate between controls that had no complex behaviors; the system's design should also enable widgets to perform custom handling as needed (i.e. for moving within a WScrollSelectList or WCombobox).

It may be worthwhile to spend some time on building basic widgets -- panes, windows, and such -- using the stock gamepad textures. It could also be a good opportunity to figure out how animations work in ESO's UI system.