DS4 Conflates IMU/Gyro with Sticks

SDL Development
1

Hello everyone! First time poster here.

I’v got some strange gamepad behaviour with my DS4 controllers that I’m trying to track down where it’s coming from.

Basically I’m getting IMU/Gyro data passed through with my controller axis calls like these:

state.left_x = SDL_GameControllerGetAxis(controller, SDL_CONTROLLER_AXIS_LEFTX);
state.left_y = SDL_GameControllerGetAxis(controller, SDL_CONTROLLER_AXIS_LEFTY);

I have been searching wide and far for information on how the DS4 motion data is being passed around in SDL2 but I just can’t find any information on it.
The above calls are meant to pick up the analogue stick and it does that fine. But sometimes I also get those variables flushed full of motion data.

Would anyone be able to point me in the direction of some info on how SDL handles IMU/movement? Or if you recognize this behavior and know whats going on?

I’m working on Raspbian Buster 32bit or a RPi4.
SDL ver: libsdl2-dev is already the newest version (2.0.9+dfsg1-1+rpt1)

Cheers, Fred

2

Searching this very forum :slight_smile: I found some more info!
Seems like there’s something in the works! https://bugzilla.libsdl.org/show_bug.cgi?id=4815

Does anyone know if this is close to being merged in, or if it should be working well enough to patch in current sdl?

Otherwise I believe that Gyro/Accel data currently comes in as a completely separate ‘Joystick’ device?

That could match what I’m observing that currently the system (not my original code) seems to add a controller when I start shaking the DS4 around.

EDIT: Is there a way to get an identification of the Joystick device that is representing the Gyro/Accel input?