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Module Sdljoystick


module Sdljoystick: sig  end
Module for SDL joystick event handling

In order to use these functions, Sdl.init must have been called with the `JOYSTICK flag. This causes SDL to scan the system for joysticks, and load appropriate drivers.

exception SDLjoystick_exception of string
exception for error reporting

type t
The joystick abstract type used to identify an SDL joystick

val num_joysticks : unit -> int
Count the number of joysticks attached to the system
val name : int -> string
Get the implementation dependent name of a joystick. This can be called before any joysticks are opened.
val open_joystick : int -> t
Open a joystick for use - the index passed as an argument refers to the N'th joystick on the system. This index is the value which will identify this joystick in future joystick events.
Raises SDLjoystick_exception if an error occurred
val opened : int -> bool
Returns true if joystick has been opened
val index : t -> int
Get the device index of an opened joystick
val num_axes : t -> int
Get the number of general axis controls on a joystick
val num_balls : t -> int
Get the number of trackballs on a joystick Joystick trackballs have only relative motion events associated with them and their state cannot be polled.
val num_hats : t -> int
Get the number of POV hats on a joystick
val num_buttons : t -> int
Get the number of buttons on a joystick


Joystick state 


val update : t -> unit
Update the current state of the open joysticks. This is called automatically by the event loop if any joystick events are enabled.

Enable/disable joystick event polling. If joystick events are disabled, you must call Sdljoystick.update yourself and check the state of the joystick when you want joystick information.

val set_event_state : bool -> unit
val get_event_state : unit -> bool

type hat_value = int 
val hat_centered : hat_value
val hat_up : hat_value
val hat_right : hat_value
val hat_down : hat_value
val hat_left : hat_value
val hat_rightup : hat_value
val hat_rightdown : hat_value
val hat_leftup : hat_value
val hat_leftdown : hat_value
val get_axis : t -> int -> int
val get_hat : t -> int -> hat_value
val get_ball : t -> int -> int * int
val get_button : t -> int -> bool
val close : t -> unit
Close a joystick previously opened with Sdljoystick.open_joystick