Initial game controller support.
Actions are based on the Switch branch but the controller code itself is
implemented differently, allowing for easy remapping and minimizing
changes to the Source/ directory.
Many subtle and not so subtle controller bugs have been fixed
in this implementation, including:
1. Smoother & more responsive movement with the joysticks.
2. Consistent controls for all the menus in the game (stores, quest log,
etc).
3. Cursor appearance / disappearance at appropriate times.
Low-level controls are abstracted and 3 SDL interfaces are supported:
game controller, joystick, and keyboard. See SourceX/controls/ for more
details on this.
Wishlist for the future:
1. Primary button and use button should attack continously.
This is hard as it requires checking the cooldowns / attack speed.
2. Quick spell menu navigation is very buggy. It is also buggy in the
switch branch. I haven't had a change to investigate.
Gleb Mazovetskiy
a2e821d241