###### (This is the documentation for SDL3, which is the current stable version. [SDL2](https://wiki.libsdl.org/SDL2/) was the previous version!)
# SDL_SetJoystickVirtualBall

Generate ball motion on an opened virtual joystick.

## Header File

Defined in [<SDL3/SDL_joystick.h>](https://github.com/libsdl-org/SDL/blob/main/include/SDL3/SDL_joystick.h)

## Syntax

```c
bool SDL_SetJoystickVirtualBall(SDL_Joystick *joystick, int ball, Sint16 xrel, Sint16 yrel);
```

## Function Parameters

|                                |              |                                                          |
| ------------------------------ | ------------ | -------------------------------------------------------- |
| [SDL_Joystick](SDL_Joystick) * | **joystick** | the virtual joystick on which to set state.              |
| int                            | **ball**     | the index of the ball on the virtual joystick to update. |
| [Sint16](Sint16)               | **xrel**     | the relative motion on the X axis.                       |
| [Sint16](Sint16)               | **yrel**     | the relative motion on the Y axis.                       |

## Return Value

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

## Remarks

Please note that values set here will not be applied until the next call to
[SDL_UpdateJoysticks](SDL_UpdateJoysticks), which can either be called
directly, or can be called indirectly through various other SDL APIs,
including, but not limited to the following:
[SDL_PollEvent](SDL_PollEvent), [SDL_PumpEvents](SDL_PumpEvents),
[SDL_WaitEventTimeout](SDL_WaitEventTimeout),
[SDL_WaitEvent](SDL_WaitEvent).

## Version

This function is available since SDL 3.1.3.

----
[CategoryAPI](CategoryAPI), [CategoryAPIFunction](CategoryAPIFunction), [CategoryJoystick](CategoryJoystick)