It would be easy to assume that all APIs that reference
SDL_JOYSTICK_AXIS_MAX work the same way, but they do not: triggers
generally use the full signed 16-bit range in the lower-level joystick
API, but are normalized to be non-negative by the higher-level gamepad
API.
We also never said explicitly which direction is positive here.
Experimentally, it's right (X), down (Y), and pressed (triggers).
Resolves: https://github.com/libsdl-org/SDL/issues/8793
Signed-off-by: Simon McVittie <smcv@collabora.com>
Simon McVittie
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