So, I cannot figure out how to set multiple keybindings in the Settings > Control menu. I did figure out how to do it by modifying the game’s controls.json file, and since I have not seen that explanation posted in these forums yet, I figured I would add a guide in case others have the same question.
I want to set multiple key bindings to the “Next Item” and “Previous Item” controls under Item Management. I found my controls.json in the windows Steam userdata directory: C:\Program Files (x86)\Steam\userdata\###\###\local\user_settings\default .
The contents of that file are normal JSON data, and the relevant field is the PLAYING > controlscheme > buttons field. By default it is null (no overrides) so to add overrides I changed it to:
{"KEYBOARD":[{"action":"ITEM_NEXT","input":"25"},{"action":"ITEM_PREVIOUS","input":"23"}],"MOUSE_WHEEL":[{"action":"ITEM_NEXT","input":"0"},{"action":"ITEM_PREVIOUS","input":"1"}]}
Which is to say that the entire section went from looking like:
"PLAYING":{"controlscheme":{"axes":null,"buttons":null}}
To looking like:
"PLAYING":{"controlscheme":{"axes":null,"buttons":{"KEYBOARD":[{"action":"ITEM_NEXT","input":"25"},{"action":"ITEM_PREVIOUS","input":"23"}],"MOUSE_WHEEL":[{"action":"ITEM_NEXT","input":"0"},{"action":"ITEM_PREVIOUS","input":"1"}]}}}
That set my “Next Item” to the Z button on the keyboard (input 25 – which also unsets the default for “Holster Tools”) and mouse wheel up as the second binding. I could have added multiple keyboard bindings by adding multiples for the same action in the KEYBOARD array, such as {"action":"ITEM_NEXT","input":"0"}. I also did the X keyboard button and mouse wheel down for “Previous Item”.
I recommend if you want to change other settings you just change them to one of the desired buttons in the game’s GUI first and then add the multiple keybindings in this file. I don’t know for sure where the ITEM_NEXT and ITEM_PREVIOUS enum names come from – I suspect they are discoverable from the game’s lang,json, all keys starting with GUI_ACTION_*, e.g. GUI_ACTION_ITEM_NEXT in C:\Program Files (x86)\Steam\steamapps\common\Boundless\assets\archetypes\strings\english.json or wherever your Boundless/Steam game files are stored. Still, it will be easier to just jump start it by using the GUI first and adding the additional keybindings this way.
If someone replies to this thread telling me how to do multiple keybindings in the GUI, well, then, let this serve as an educational reference for the curious 