====== (This is the legacy documentation for stable SDL2, the current stable version; [https://wiki.libsdl.org/SDL3/ SDL3] is the current development version.) ====== = SDL_JoystickGetBall = Get the ball axis change since the last poll. == Syntax == int SDL_JoystickGetBall(SDL_Joystick *joystick, int ball, int *dx, int *dy); == Function 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 0 on success or a negative error code on failure; call [[SDL_GetError]]() for more information. == Remarks == Trackballs can only return relative motion since the last call to [[SDL_JoystickGetBall]](), these motion deltas are placed into dx and dy. Most joysticks do not have trackballs. == Version == This function is available since SDL 2.0.0. == Related Functions == :[[SDL_JoystickNumBalls]] ---- [[CategoryAPI]]