Function SDL_GetJoystickBall

pub unsafe extern "C" fn SDL_GetJoystickBall(
    joystick: *mut SDL_Joystick,
    ball: i32,
    dx: *mut i32,
    dy: *mut i32,
) -> bool

Available on crate feature dep_sdl3 only.

Get the ball axis change since the last poll.

Trackballs can only return relative motion since the last call to SDL_GetJoystickBall(), these motion deltas are placed into dx and dy.

Most joysticks do not have trackballs.

Parameters

• joystick: the SDL_Joystick to query.
• ball: the ball index to query; ball indices start at index 0.
• dx: stores the difference in the x axis position since the last poll.
• dy: stores the difference in the y axis position since the last poll.

Return value

Returns true on success or false on failure; call SDL_GetError() for more information.

Availability

This function is available since SDL 3.2.0.

See also

• SDL_GetNumJoystickBalls