SDL_JoyBallEvent(3) SDL API Reference SDL_JoyBallEvent(3)NAME
SDL_JoyBallEvent- Joystick trackball motion event struc-
ture
STRUCTURE DEFINITION
typedef struct{
Uint8 type;
Uint8 which;
Uint8 ball;
Sint16 xrel, yrel;
} SDL_JoyBallEvent;
STRUCTURE DATA
type SDL_JOYBALLMOTION
which Joystick device index
ball Joystick trackball index
xrel, yrel The relative motion in the X/Y direc-
tion
DESCRIPTIONSDL_JoyBallEvent is a member of the SDL_Event union and is
used when an event of type SDL_JOYBALLMOTION is reported.
A SDL_JOYBALLMOTION event occurs when a user moves a
trackball on the joystick. The field which is the index of
the joystick that reported the event and ball is the index
of the trackball (for a more detailed explaination see the
Joystick section). Trackballs only return relative motion,
this is the change in position on the ball since it was
last polled (last cycle of the event loop) and it is
stored in xrel and yrel.
SEE ALSO
SDL_Event, Joystick Functions, SDL_JoystickEventState,
SDL_JoystickGetBall
SDL Tue 11 Sep 2001, 22:59 SDL_JoyBallEvent(3)