wayland-protocols: Add gaming-input-unstable-v1 protocol

third_party/wayland-protocols/unstable/gamepads/gamepads-unstable-v1.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<protocol name="gamepads_unstable_v1">
+
+  <copyright>
+    Copyright 2016 The Chromium Authors.
+
+    Permission is hereby granted, free of charge, to any person obtaining a
+    copy of this software and associated documentation files (the "Software"),
+    to deal in the Software without restriction, including without limitation
+    the rights to use, copy, modify, merge, publish, distribute, sublicense,
+    and/or sell copies of the Software, and to permit persons to whom the
+    Software is furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice (including the next
+    paragraph) shall be included in all copies or substantial portions of the
+    Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+    DEALINGS IN THE SOFTWARE.
+  </copyright>
+
+  <interface name="zwp_gamepads_v1" version="1">

[reveman, 2016/06/23 21:34:20]

is this a global? it would be nice if this was consistent with other input
devices and the client could ask for the gamepad interface for a seat. is that
possible?

[denniskempin, 2016/06/28 20:15:33]

Done.

+    <description summary="gamepad support">
+      A global interface to notify the client of any gamepads connected to the
+      server.
+      All gamepads axes and buttons follow the W3C definition of a
+      'Standard Gamepad' as specified in: https://w3c.github.io/gamepad/#remapping
+    </description>
+
+    <event name="connected">
+      <description summary="A new gamepad connected">
+        Every gamepad gets an assigned an incrementing id, starting with 0.
+        This event is called before any other event for the gamepad will be
+        sent.
+      </description>
+      <arg name="id" type="int" summary="id of the gamepad"/>
+    </event>
+
+    <event name="disconnected">
+      <description summary="A gamepad disconnected">
+        Called after a gamepad is disconnected, no further events for this
+        gamepad shall be sent by the server.
+      </description>
+      <arg name="id" type="int" summary="id of the gamepad"/>
+    </event>
+
+    <event name="axis">
+      <description summary="Gamepad analog axis changed">
+        Sent when a gamepad axis changed. Follows the W3C specification of
+        gamepad axes, which has 2 analog sticks resulting in 4 axes, which
+        are identified by the axis argument.
+
+        The value is normalized and calibrated, with 0 in the resting state,
+        -1 at the left/top corner of the stick and 1 at the right/bottom corner.
+
+        This event should not cause any changes to the client until the
+        frame event is received.
+      </description>
+      <arg name="id" type="int" summary="id of the gamepad"/>
+      <arg name="axis" type="int" summary="id of axis"/>
+      <arg name="value" type="fixed" summary="new value of axis"/>
+    </event>
+
+    <event name="button">
+      <description summary="Gamepad button changed">
+        Sent when a gamepad button state changed. Follows the W3C specification
+        of gamepad buttons, which has 17 possible buttons.
+
+        All buttons have a boolean state and an analog value. The analog value
+        is normalized from 0 (not pressed) to 1 (fully pressed), if a button
+        does not support an analog value, the value will be derived from the
+        boolean state.
+
+        This event should not cause any changes to the client until the
+        frame event is received.
+      </description>
+      <arg name="id" type="int" summary="id of the gamepad"/>
+      <arg name="button" type="int" summary="id of button"/>
+      <arg name="pressed" type="int" summary="boolean state of the button"/>
+      <arg name="value" type="fixed" summary="new analog value of button"/>
+    </event>
+
+    <event name="frame">
+      <description summary="Notifies end of a series of gamepad changes.">
+        Sent after a series of axis and button events that logically belong
+        together.
+      </description>
+      <arg name="time" type="uint" summary="timestamp with millisecond granularity"/>
+    </event>
+
+    <request name="destroy" type="destructor">
+      <description summary="destroy gamepads object">
+      </description>
+    </request>
+  </interface>
+
+

[reveman, 2016/06/23 21:34:19]

nit: kill blank line

[denniskempin, 2016/06/28 20:15:33]

Done.

+</protocol>