An add-on for the Unity InputSystem package that provides additional input backends, including proper HID support on Linux, and raw Xbox One controller support via GameInput on Windows.
(pronounced "hydrogen" or "hid-rogen")
After installation, this package integrates and operates on its own. No manual initialization or interaction is required.
Some configuration is available through compile-defines. These defines apply to all backends:
HIDROGEN_VERBOSE_LOGGING: Enables verbose logging to help debug issues with devices.
This backend provides raw HID support on Linux through the hidraw kernel driver. Raw input/output reports and device descriptor retrieval are implemented, which allows the built-in HID functionality of the input system to work as expected, including custom device layouts.
This backend relies on the hidraw version of hidapi for input, along with libudev for device connection/disconnection monitoring. By installing this package, your project will become dependent on them as well on Linux. On distributions that use apt, the following command should do the trick:
sudo apt install libhidapi-hidraw0 libudev1
The user will also need to install some udev rules in order to allow accessing hidraw devices without elevated priveleges:
# If you just want specific devices, you can specify them by vendor/product ID with the following.
KERNEL=="hidraw*", ATTRS{idVendor}=="04d8", ATTRS{idProduct}=="003f", TAG+="uaccess"
# If you want *all* hidraw devices, you can omit the attributes and just set the access tag.
KERNEL=="hidraw*", TAG+="uaccess"
# There does not appear to be any way to filter by usage/usage page through ATTRS alone.
# If it is possible, it requires udev rule knowledge I do not possess at the time of writing.
The rules file should be placed in /etc/udev/rules.d or /usr/lib/udev/rules.d/, and it must come before 73-seat-late.rules.
Some configuration is available through compile-defines:
HIDROGEN_FORCE_REPORT_IDS: By default, report IDs are not provided if a device doesn't use them. This define will make state events always include the report ID byte as the first byte. This behavior is disabled by default, since that's how hidapi/hidraw provides inputs.
This backend provides raw Xbox One controller support through the GameInput API on Windows. Raw inputs and outputs are supported, allowing similar custom device layout support as with HID devices.
This backend depends on GameInput being installed on the user's system. Although it is installed by default on recent versions of Windows, there is a redistributable that is recommended to be used in an installer bundle to provide compatibility with older versions. Refer to the GameInput documentation for full details.
- As of the time of writing, the GameInput function that is responsible for sending raw output reports is not currently implemented. All output commands will silently fail until it gets implemented. (Only the
E_NOTIMPLHRESULT is treated as success, all others will be logged and generate a proper failure code.) - Gamepads reported through GameInput are ignored, to ensure no duplicate devices will occur between GameInput and XInput.
This backend reintroduces XInput support to Unity 2022.2 and onward; starting from 2022.2 they switched to Windows.Gaming.Input for gamepad support. All existing XInput layouts and commands are supported through this backend, except for gamepads, which will be handled by the native backend already and are ignored.
- This backend will only enable itself in Unity 2022.2 and onward. No special setup is needed for it.
- This backend does not respect the
InputSystem.pollingFrequencysetting currently, it uses a hard-set sleep time of 1 ms.
This project is licensed under the MIT license. See LICENSE.md for details.