Gamepad.Wire (gamepad v0.1.0)

The line protocol between Gamepad and a platform helper, and the event maps a controller produces.

A helper writes one line per event to its standard output:

device <id> <name...>
gone <id>
button <id> <button> <0|1>
axis <id> <axis> <value>

id is a small integer the helper assigns per connected controller. Buttons and axes use the Xbox layout names below whatever the hardware is; a helper maps its platform's names to these. Axis values are floats: sticks from -1.0 (left or up) to 1.0 (right or down), triggers from 0.0 to 1.0.

parse/1 turns a line into the event map delivered by Gamepad:

%{type: :connected, device: id, name: name}
%{type: :disconnected, device: id}
%{type: :button, device: id, button: button, pressed: boolean}
%{type: :axis, device: id, axis: axis, value: float}

A line that is not one of these parses to nil.

Summary

Types

axis()

button()

event()

Functions

axes()

The axis names.

buttons()

The button names, in the Xbox layout.

parse(line)

The event a helper line describes, or nil for a line that is not an event.

Types

axis()

@type axis() ::
  :left_x | :left_y | :right_x | :right_y | :left_trigger | :right_trigger

button()

@type button() ::
  :a
  | :b
  | :x
  | :y
  | :left_bumper
  | :right_bumper
  | :back
  | :start
  | :guide
  | :left_stick
  | :right_stick
  | :dpad_up
  | :dpad_down
  | :dpad_left
  | :dpad_right

event()

@type event() ::
  %{type: :connected, device: non_neg_integer(), name: String.t()}
  | %{type: :disconnected, device: non_neg_integer()}
  | %{
      type: :button,
      device: non_neg_integer(),
      button: button(),
      pressed: boolean()
    }
  | %{type: :axis, device: non_neg_integer(), axis: axis(), value: float()}

Functions

axes()

@spec axes() :: [axis()]

The axis names.

buttons()

@spec buttons() :: [button()]

The button names, in the Xbox layout.

parse(line)

@spec parse(String.t()) :: event() | nil

The event a helper line describes, or nil for a line that is not an event.

iex> Gamepad.Wire.parse("button 0 a 1")
%{type: :button, device: 0, button: :a, pressed: true}

iex> Gamepad.Wire.parse("axis 2 left_y -0.25")
%{type: :axis, device: 2, axis: :left_y, value: -0.25}

iex> Gamepad.Wire.parse("device 0 Xbox Wireless Controller")
%{type: :connected, device: 0, name: "Xbox Wireless Controller"}

iex> Gamepad.Wire.parse("gone 0")
%{type: :disconnected, device: 0}

iex> Gamepad.Wire.parse("button 0 select 1")
nil