SDL_JoyBallEvent — Joystick trackball motion event structure
typedef | struct { | |||
Uint8 |
type ; |
|||
Uint8 |
which ; |
|||
Uint8 |
ball ; |
|||
Sint16 |
xrel , |
|||
yrel ; |
||||
} SDL_JoyBallEvent; |
type
SDL_JOYBALLMOTION
which
Joystick device index
ball
Joystick trackball index
xrel
, yrel
The relative motion in the X/Y direction
SDL_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
.
SDL_Event(3), Joystick Functions, SDL_JoystickEventState(3), SDL_JoystickGetBall(3)
COPYRIGHT |
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This manual page is taken from the SDL library, licensed under GNU LGPL. |