Almost any modern game will allow the player to change their input bindings. However, in GC the input is tightly coupled to the trigger system and it doesn't appear to be possible to give the player the ability to rebind their keys/buttons while playing the game. I would strongly suggest that such a feature be made part of the core module. Not only is this an expected feature in most games, but it is also an issue for people who have physical impairments and cannot use every control scheme or controller. I personally can't imagine releasing a non-free game and not allowing the player to change their input bindings.
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