SDL

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<?xml version="1.0" encoding="UTF-8"?>
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<protocol name="tablet_v2">
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  <copyright>
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    Copyright 2014 © Stephen "Lyude" Chandler Paul
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    Copyright 2015-2016 © Red Hat, Inc.
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    Permission is hereby granted, free of charge, to any person
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    obtaining a copy of this software and associated documentation files
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    (the "Software"), to deal in the Software without restriction,
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    including without limitation the rights to use, copy, modify, merge,
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    publish, distribute, sublicense, and/or sell copies of the Software,
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    and to permit persons to whom the Software is furnished to do so,
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    subject to the following conditions:
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    The above copyright notice and this permission notice (including the
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    next paragraph) shall be included in all copies or substantial
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    portions of the Software.
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    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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    NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
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    BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
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    ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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    CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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    SOFTWARE.
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  </copyright>
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  <description summary="Wayland protocol for graphics tablets">
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    This description provides a high-level overview of the interplay between
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    the interfaces defined this protocol. For details, see the protocol
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    specification.
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    More than one tablet may exist, and device-specifics matter. Tablets are
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    not represented by a single virtual device like wl_pointer. A client
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    binds to the tablet manager object which is just a proxy object. From
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    that, the client requests wp_tablet_manager.get_tablet_seat(wl_seat)
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    and that returns the actual interface that has all the tablets. With
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    this indirection, we can avoid merging wp_tablet into the actual Wayland
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    protocol, a long-term benefit.
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    The wp_tablet_seat sends a "tablet added" event for each tablet
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    connected. That event is followed by descriptive events about the
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    hardware; currently that includes events for name, vid/pid and
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    a wp_tablet.path event that describes a local path. This path can be
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    used to uniquely identify a tablet or get more information through
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    libwacom. Emulated or nested tablets can skip any of those, e.g. a
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    virtual tablet may not have a vid/pid. The sequence of descriptive
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    events is terminated by a wp_tablet.done event to signal that a client
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    may now finalize any initialization for that tablet.
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    Events from tablets require a tool in proximity. Tools are also managed
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    by the tablet seat; a "tool added" event is sent whenever a tool is new
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    to the compositor. That event is followed by a number of descriptive
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    events about the hardware; currently that includes capabilities,
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    hardware id and serial number, and tool type. Similar to the tablet
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    interface, a wp_tablet_tool.done event is sent to terminate that initial
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    sequence.
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    Any event from a tool happens on the wp_tablet_tool interface. When the
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    tool gets into proximity of the tablet, a proximity_in event is sent on
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    the wp_tablet_tool interface, listing the tablet and the surface. That
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    event is followed by a motion event with the coordinates. After that,
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    it's the usual motion, axis, button, etc. events. The protocol's
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    serialisation means events are grouped by wp_tablet_tool.frame events.
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    Two special events (that don't exist in X) are down and up. They signal
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    "tip touching the surface". For tablets without real proximity
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    detection, the sequence is: proximity_in, motion, down, frame.
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    When the tool leaves proximity, a proximity_out event is sent. If any
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    button is still down, a button release event is sent before this
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    proximity event. These button events are sent in the same frame as the
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    proximity event to signal to the client that the buttons were held when
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    the tool left proximity.
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    If the tool moves out of the surface but stays in proximity (i.e.
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    between windows), compositor-specific grab policies apply. This usually
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    means that the proximity-out is delayed until all buttons are released.
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    Moving a tool physically from one tablet to the other has no real effect
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    on the protocol, since we already have the tool object from the "tool
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    added" event. All the information is already there and the proximity
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    events on both tablets are all a client needs to reconstruct what
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    happened.
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    Some extra axes are normalized, i.e. the client knows the range as
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    specified in the protocol (e.g. [0, 65535]), the granularity however is
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    unknown. The current normalized axes are pressure, distance, and slider.
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    Other extra axes are in physical units as specified in the protocol.
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    The current extra axes with physical units are tilt, rotation and
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    wheel rotation.
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    Since tablets work independently of the pointer controlled by the mouse,
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    the focus handling is independent too and controlled by proximity.
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    The wp_tablet_tool.set_cursor request sets a tool-specific cursor.
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    This cursor surface may be the same as the mouse cursor, and it may be
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    the same across tools but it is possible to be more fine-grained. For
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    example, a client may set different cursors for the pen and eraser.
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    Tools are generally independent of tablets and it is
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    compositor-specific policy when a tool can be removed. Common approaches
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    will likely include some form of removing a tool when all tablets the
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    tool was used on are removed.
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  </description>
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  <interface name="zwp_tablet_manager_v2" version="1">
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    <description summary="controller object for graphic tablet devices">
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      An object that provides access to the graphics tablets available on this
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      system. All tablets are associated with a seat, to get access to the
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      actual tablets, use wp_tablet_manager.get_tablet_seat.
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    </description>
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    <request name="get_tablet_seat">
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      <description summary="get the tablet seat">
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	Get the wp_tablet_seat object for the given seat. This object
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	provides access to all graphics tablets in this seat.
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      </description>
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      <arg name="tablet_seat" type="new_id" interface="zwp_tablet_seat_v2"/>
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      <arg name="seat" type="object" interface="wl_seat" summary="The wl_seat object to retrieve the tablets for" />
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    </request>
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    <request name="destroy" type="destructor">
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      <description summary="release the memory for the tablet manager object">
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	Destroy the wp_tablet_manager object. Objects created from this
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	object are unaffected and should be destroyed separately.
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      </description>
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    </request>
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  </interface>
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  <interface name="zwp_tablet_seat_v2" version="1">
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    <description summary="controller object for graphic tablet devices of a seat">
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      An object that provides access to the graphics tablets available on this
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      seat. After binding to this interface, the compositor sends a set of
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      wp_tablet_seat.tablet_added and wp_tablet_seat.tool_added events.
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    </description>
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    <request name="destroy" type="destructor">
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      <description summary="release the memory for the tablet seat object">
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	Destroy the wp_tablet_seat object. Objects created from this
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	object are unaffected and should be destroyed separately.
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      </description>
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    </request>
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    <event name="tablet_added">
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      <description summary="new device notification">
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	This event is sent whenever a new tablet becomes available on this
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	seat. This event only provides the object id of the tablet, any
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	static information about the tablet (device name, vid/pid, etc.) is
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	sent through the wp_tablet interface.
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      </description>
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      <arg name="id" type="new_id" interface="zwp_tablet_v2" summary="the newly added graphics tablet"/>
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    </event>
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    <event name="tool_added">
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      <description summary="a new tool has been used with a tablet">
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	This event is sent whenever a tool that has not previously been used
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	with a tablet comes into use. This event only provides the object id
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	of the tool; any static information about the tool (capabilities,
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	type, etc.) is sent through the wp_tablet_tool interface.
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      </description>
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      <arg name="id" type="new_id" interface="zwp_tablet_tool_v2" summary="the newly added tablet tool"/>
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    </event>
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    <event name="pad_added">
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      <description summary="new pad notification">
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	This event is sent whenever a new pad is known to the system. Typically,
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	pads are physically attached to tablets and a pad_added event is
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	sent immediately after the wp_tablet_seat.tablet_added.
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	However, some standalone pad devices logically attach to tablets at
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	runtime, and the client must wait for wp_tablet_pad.enter to know
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	the tablet a pad is attached to.
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	This event only provides the object id of the pad. All further
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	features (buttons, strips, rings) are sent through the wp_tablet_pad
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	interface.
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      </description>
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      <arg name="id" type="new_id" interface="zwp_tablet_pad_v2" summary="the newly added pad"/>
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    </event>
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  </interface>
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  <interface name="zwp_tablet_tool_v2" version="1">
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    <description summary="a physical tablet tool">
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      An object that represents a physical tool that has been, or is
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      currently in use with a tablet in this seat. Each wp_tablet_tool
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      object stays valid until the client destroys it; the compositor
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      reuses the wp_tablet_tool object to indicate that the object's
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      respective physical tool has come into proximity of a tablet again.
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      A wp_tablet_tool object's relation to a physical tool depends on the
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      tablet's ability to report serial numbers. If the tablet supports
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      this capability, then the object represents a specific physical tool
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      and can be identified even when used on multiple tablets.
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      A tablet tool has a number of static characteristics, e.g. tool type,
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      hardware_serial and capabilities. These capabilities are sent in an
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      event sequence after the wp_tablet_seat.tool_added event before any
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      actual events from this tool. This initial event sequence is
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      terminated by a wp_tablet_tool.done event.
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      Tablet tool events are grouped by wp_tablet_tool.frame events.
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      Any events received before a wp_tablet_tool.frame event should be
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      considered part of the same hardware state change.
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    </description>
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    <request name="set_cursor">
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      <description summary="set the tablet tool's surface">
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	Sets the surface of the cursor used for this tool on the given
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	tablet. This request only takes effect if the tool is in proximity
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	of one of the requesting client's surfaces or the surface parameter
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	is the current pointer surface. If there was a previous surface set
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	with this request it is replaced. If surface is NULL, the cursor
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	image is hidden.
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	The parameters hotspot_x and hotspot_y define the position of the
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	pointer surface relative to the pointer location. Its top-left corner
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	is always at (x, y) - (hotspot_x, hotspot_y), where (x, y) are the
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	coordinates of the pointer location, in surface-local coordinates.
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	On surface.attach requests to the pointer surface, hotspot_x and
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	hotspot_y are decremented by the x and y parameters passed to the
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	request. Attach must be confirmed by wl_surface.commit as usual.
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	The hotspot can also be updated by passing the currently set pointer
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	surface to this request with new values for hotspot_x and hotspot_y.
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	The current and pending input regions of the wl_surface are cleared,
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	and wl_surface.set_input_region is ignored until the wl_surface is no
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	longer used as the cursor. When the use as a cursor ends, the current
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	and pending input regions become undefined, and the wl_surface is
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	unmapped.
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	This request gives the surface the role of a wp_tablet_tool cursor. A
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	surface may only ever be used as the cursor surface for one
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	wp_tablet_tool. If the surface already has another role or has
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	previously been used as cursor surface for a different tool, a
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	protocol error is raised.
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      </description>
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      <arg name="serial" type="uint" summary="serial of the proximity_in event"/>
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      <arg name="surface" type="object" interface="wl_surface" allow-null="true"/>
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      <arg name="hotspot_x" type="int" summary="surface-local x coordinate"/>
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      <arg name="hotspot_y" type="int" summary="surface-local y coordinate"/>
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    </request>
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    <request name="destroy" type="destructor">
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      <description summary="destroy the tool object">
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	This destroys the client's resource for this tool object.
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      </description>
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    </request>
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    <enum name="type">
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      <description summary="a physical tool type">
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	Describes the physical type of a tool. The physical type of a tool
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	generally defines its base usage.
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	The mouse tool represents a mouse-shaped tool that is not a relative
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	device but bound to the tablet's surface, providing absolute
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	coordinates.
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	The lens tool is a mouse-shaped tool with an attached lens to
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	provide precision focus.
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      </description>
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      <entry name="pen" value="0x140" summary="Pen"/>
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      <entry name="eraser" value="0x141" summary="Eraser"/>
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      <entry name="brush" value="0x142" summary="Brush"/>
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      <entry name="pencil" value="0x143" summary="Pencil"/>
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      <entry name="airbrush" value="0x144" summary="Airbrush"/>
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      <entry name="finger" value="0x145" summary="Finger"/>
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      <entry name="mouse" value="0x146" summary="Mouse"/>
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      <entry name="lens" value="0x147" summary="Lens"/>
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    </enum>
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    <event name="type">
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      <description summary="tool type">
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	The tool type is the high-level type of the tool and usually decides
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	the interaction expected from this tool.
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	This event is sent in the initial burst of events before the
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	wp_tablet_tool.done event.
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      </description>
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      <arg name="tool_type" type="uint" enum="type" summary="the physical tool type"/>
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    </event>
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    <event name="hardware_serial">
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      <description summary="unique hardware serial number of the tool">
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	If the physical tool can be identified by a unique 64-bit serial
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	number, this event notifies the client of this serial number.
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	If multiple tablets are available in the same seat and the tool is
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	uniquely identifiable by the serial number, that tool may move
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	between tablets.
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	Otherwise, if the tool has no serial number and this event is
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	missing, the tool is tied to the tablet it first comes into
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	proximity with. Even if the physical tool is used on multiple
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	tablets, separate wp_tablet_tool objects will be created, one per
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	tablet.
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	This event is sent in the initial burst of events before the
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	wp_tablet_tool.done event.
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      </description>
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      <arg name="hardware_serial_hi" type="uint" summary="the unique serial number of the tool, most significant bits"/>
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      <arg name="hardware_serial_lo" type="uint" summary="the unique serial number of the tool, least significant bits"/>
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    </event>
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    <event name="hardware_id_wacom">
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      <description summary="hardware id notification in Wacom's format">
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	This event notifies the client of a hardware id available on this tool.
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	The hardware id is a device-specific 64-bit id that provides extra
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	information about the tool in use, beyond the wl_tool.type
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	enumeration. The format of the id is specific to tablets made by
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	Wacom Inc. For example, the hardware id of a Wacom Grip
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	Pen (a stylus) is 0x802.
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	This event is sent in the initial burst of events before the
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	wp_tablet_tool.done event.
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      </description>
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      <arg name="hardware_id_hi" type="uint" summary="the hardware id, most significant bits"/>
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      <arg name="hardware_id_lo" type="uint" summary="the hardware id, least significant bits"/>
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    </event>
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    <enum name="capability">
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      <description summary="capability flags for a tool">
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	Describes extra capabilities on a tablet.
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	Any tool must provide x and y values, extra axes are
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	device-specific.
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      </description>
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      <entry name="tilt" value="1" summary="Tilt axes"/>
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      <entry name="pressure" value="2" summary="Pressure axis"/>
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      <entry name="distance" value="3" summary="Distance axis"/>
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      <entry name="rotation" value="4" summary="Z-rotation axis"/>
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      <entry name="slider" value="5" summary="Slider axis"/>
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      <entry name="wheel" value="6" summary="Wheel axis"/>
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    </enum>
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    <event name="capability">
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      <description summary="tool capability notification">
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	This event notifies the client of any capabilities of this tool,
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	beyond the main set of x/y axes and tip up/down detection.
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	One event is sent for each extra capability available on this tool.
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	This event is sent in the initial burst of events before the
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	wp_tablet_tool.done event.
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      </description>
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      <arg name="capability" type="uint" enum="capability" summary="the capability"/>
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    </event>
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    <event name="done">
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      <description summary="tool description events sequence complete">
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	This event signals the end of the initial burst of descriptive
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	events. A client may consider the static description of the tool to
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	be complete and finalize initialization of the tool.
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      </description>
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    </event>
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    <event name="removed">
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      <description summary="tool removed">
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	This event is sent when the tool is removed from the system and will
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	send no further events. Should the physical tool come back into
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	proximity later, a new wp_tablet_tool object will be created.
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	It is compositor-dependent when a tool is removed. A compositor may
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	remove a tool on proximity out, tablet removal or any other reason.
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	A compositor may also keep a tool alive until shutdown.
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	If the tool is currently in proximity, a proximity_out event will be
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	sent before the removed event. See wp_tablet_tool.proximity_out for
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	the handling of any buttons logically down.
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	When this event is received, the client must wp_tablet_tool.destroy
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	the object.
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      </description>
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    </event>
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    <event name="proximity_in">
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      <description summary="proximity in event">
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	Notification that this tool is focused on a certain surface.
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	This event can be received when the tool has moved from one surface to
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	another, or when the tool has come back into proximity above the
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	surface.
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	If any button is logically down when the tool comes into proximity,
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	the respective button event is sent after the proximity_in event but
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	within the same frame as the proximity_in event.
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      </description>
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      <arg name="serial" type="uint"/>
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      <arg name="tablet" type="object" interface="zwp_tablet_v2" summary="The tablet the tool is in proximity of"/>
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      <arg name="surface" type="object" interface="wl_surface" summary="The current surface the tablet tool is over"/>
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    </event>
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    <event name="proximity_out">
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      <description summary="proximity out event">
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	Notification that this tool has either left proximity, or is no
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	longer focused on a certain surface.
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	When the tablet tool leaves proximity of the tablet, button release
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	events are sent for each button that was held down at the time of
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	leaving proximity. These events are sent before the proximity_out
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	event but within the same wp_tablet.frame.
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	If the tool stays within proximity of the tablet, but the focus
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	changes from one surface to another, a button release event may not
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	be sent until the button is actually released or the tool leaves the
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	proximity of the tablet.
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      </description>
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    </event>
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    <event name="down">
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      <description summary="tablet tool is making contact">
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	Sent whenever the tablet tool comes in contact with the surface of the
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	tablet.
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	If the tool is already in contact with the tablet when entering the
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	input region, the client owning said region will receive a
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	wp_tablet.proximity_in event, followed by a wp_tablet.down
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	event and a wp_tablet.frame event.
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	Note that this event describes logical contact, not physical
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	contact. On some devices, a compositor may not consider a tool in
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	logical contact until a minimum physical pressure threshold is
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	exceeded.
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      </description>
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      <arg name="serial" type="uint"/>
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    </event>
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    <event name="up">
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      <description summary="tablet tool is no longer making contact">
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	Sent whenever the tablet tool stops making contact with the surface of
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	the tablet, or when the tablet tool moves out of the input region
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	and the compositor grab (if any) is dismissed.
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	If the tablet tool moves out of the input region while in contact
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	with the surface of the tablet and the compositor does not have an
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	ongoing grab on the surface, the client owning said region will
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	receive a wp_tablet.up event, followed by a wp_tablet.proximity_out
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	event and a wp_tablet.frame event. If the compositor has an ongoing
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	grab on this device, this event sequence is sent whenever the grab
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	is dismissed in the future.
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	Note that this event describes logical contact, not physical
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	contact. On some devices, a compositor may not consider a tool out
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	of logical contact until physical pressure falls below a specific
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	threshold.
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      </description>
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    </event>
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    <event name="motion">
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      <description summary="motion event">
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	Sent whenever a tablet tool moves.
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      </description>
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      <arg name="x" type="fixed" summary="surface-local x coordinate"/>
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      <arg name="y" type="fixed" summary="surface-local y coordinate"/>
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    </event>
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    <event name="pressure">
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      <description summary="pressure change event">
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	Sent whenever the pressure axis on a tool changes. The value of this
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	event is normalized to a value between 0 and 65535.
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	Note that pressure may be nonzero even when a tool is not in logical
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	contact. See the down and up events for more details.
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      </description>
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      <arg name="pressure" type="uint" summary="The current pressure value"/>
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    </event>
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    <event name="distance">
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      <description summary="distance change event">
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	Sent whenever the distance axis on a tool changes. The value of this
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	event is normalized to a value between 0 and 65535.
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	Note that distance may be nonzero even when a tool is not in logical
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	contact. See the down and up events for more details.
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      </description>
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      <arg name="distance" type="uint" summary="The current distance value"/>
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    </event>
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    <event name="tilt">
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      <description summary="tilt change event">
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	Sent whenever one or both of the tilt axes on a tool change. Each tilt
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	value is in degrees, relative to the z-axis of the tablet.
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	The angle is positive when the top of a tool tilts along the
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	positive x or y axis.
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      </description>
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      <arg name="tilt_x" type="fixed" summary="The current value of the X tilt axis"/>
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      <arg name="tilt_y" type="fixed" summary="The current value of the Y tilt axis"/>
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    </event>
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    <event name="rotation">
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      <description summary="z-rotation change event">
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	Sent whenever the z-rotation axis on the tool changes. The
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	rotation value is in degrees clockwise from the tool's
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	logical neutral position.
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      </description>
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      <arg name="degrees" type="fixed" summary="The current rotation of the Z axis"/>
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    </event>
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    <event name="slider">
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      <description summary="Slider position change event">
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	Sent whenever the slider position on the tool changes. The
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	value is normalized between -65535 and 65535, with 0 as the logical
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	neutral position of the slider.
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	The slider is available on e.g. the Wacom Airbrush tool.
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      </description>
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      <arg name="position" type="int" summary="The current position of slider"/>
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    </event>
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    <event name="wheel">
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      <description summary="Wheel delta event">
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	Sent whenever the wheel on the tool emits an event. This event
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	contains two values for the same axis change. The degrees value is
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	in the same orientation as the wl_pointer.vertical_scroll axis. The
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	clicks value is in discrete logical clicks of the mouse wheel. This
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	value may be zero if the movement of the wheel was less
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	than one logical click.
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	Clients should choose either value and avoid mixing degrees and
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	clicks. The compositor may accumulate values smaller than a logical
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	click and emulate click events when a certain threshold is met.
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	Thus, wl_tablet_tool.wheel events with non-zero clicks values may
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	have different degrees values.
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      </description>
529
      <arg name="degrees" type="fixed" summary="The wheel delta in degrees"/>
530
      <arg name="clicks" type="int" summary="The wheel delta in discrete clicks"/>
531
    </event>
532

533
    <enum name="button_state">
534
      <description summary="physical button state">
535
	Describes the physical state of a button that produced the button event.
536
      </description>
537
      <entry name="released" value="0" summary="button is not pressed"/>
538
      <entry name="pressed" value="1" summary="button is pressed"/>
539
    </enum>
540

541
    <event name="button">
542
      <description summary="button event">
543
	Sent whenever a button on the tool is pressed or released.
544

545
	If a button is held down when the tool moves in or out of proximity,
546
	button events are generated by the compositor. See
547
	wp_tablet_tool.proximity_in and wp_tablet_tool.proximity_out for
548
	details.
549
      </description>
550
      <arg name="serial" type="uint"/>
551
      <arg name="button" type="uint" summary="The button whose state has changed"/>
552
      <arg name="state" type="uint" enum="button_state" summary="Whether the button was pressed or released"/>
553
    </event>
554

555
    <event name="frame">
556
      <description summary="frame event">
557
	Marks the end of a series of axis and/or button updates from the
558
	tablet. The Wayland protocol requires axis updates to be sent
559
	sequentially, however all events within a frame should be considered
560
	one hardware event.
561
      </description>
562
      <arg name="time" type="uint" summary="The time of the event with millisecond granularity"/>
563
    </event>
564

565
    <enum name="error">
566
      <entry name="role" value="0" summary="given wl_surface has another role"/>
567
    </enum>
568
  </interface>
569

570
  <interface name="zwp_tablet_v2" version="1">
571
    <description summary="graphics tablet device">
572
      The wp_tablet interface represents one graphics tablet device. The
573
      tablet interface itself does not generate events; all events are
574
      generated by wp_tablet_tool objects when in proximity above a tablet.
575

576
      A tablet has a number of static characteristics, e.g. device name and
577
      pid/vid. These capabilities are sent in an event sequence after the
578
      wp_tablet_seat.tablet_added event. This initial event sequence is
579
      terminated by a wp_tablet.done event.
580
    </description>
581

582
    <request name="destroy" type="destructor">
583
      <description summary="destroy the tablet object">
584
	This destroys the client's resource for this tablet object.
585
      </description>
586
    </request>
587

588
    <event name="name">
589
      <description summary="tablet device name">
590
        A descriptive name for the tablet device.
591

592
	If the device has no descriptive name, this event is not sent.
593

594
	This event is sent in the initial burst of events before the
595
        wp_tablet.done event.
596
      </description>
597
      <arg name="name" type="string" summary="the device name"/>
598
    </event>
599

600
    <event name="id">
601
      <description summary="tablet device USB vendor/product id">
602
	The USB vendor and product IDs for the tablet device.
603

604
	If the device has no USB vendor/product ID, this event is not sent.
605
	This can happen for virtual devices or non-USB devices, for instance.
606

607
	This event is sent in the initial burst of events before the
608
	wp_tablet.done event.
609
      </description>
610
      <arg name="vid" type="uint" summary="USB vendor id"/>
611
      <arg name="pid" type="uint" summary="USB product id"/>
612
    </event>
613

614
    <event name="path">
615
      <description summary="path to the device">
616
	A system-specific device path that indicates which device is behind
617
	this wp_tablet. This information may be used to gather additional
618
	information about the device, e.g. through libwacom.
619

620
	A device may have more than one device path. If so, multiple
621
	wp_tablet.path events are sent. A device may be emulated and not
622
	have a device path, and in that case this event will not be sent.
623

624
	The format of the path is unspecified, it may be a device node, a
625
	sysfs path, or some other identifier. It is up to the client to
626
	identify the string provided.
627

628
	This event is sent in the initial burst of events before the
629
	wp_tablet.done event.
630
      </description>
631
      <arg name="path" type="string" summary="path to local device"/>
632
    </event>
633

634
    <event name="done">
635
      <description summary="tablet description events sequence complete">
636
	This event is sent immediately to signal the end of the initial
637
	burst of descriptive events. A client may consider the static
638
	description of the tablet to be complete and finalize initialization
639
	of the tablet.
640
      </description>
641
    </event>
642

643
    <event name="removed">
644
      <description summary="tablet removed event">
645
	Sent when the tablet has been removed from the system. When a tablet
646
	is removed, some tools may be removed.
647

648
	When this event is received, the client must wp_tablet.destroy
649
	the object.
650
      </description>
651
    </event>
652
  </interface>
653

654
  <interface name="zwp_tablet_pad_ring_v2" version="1">
655
    <description summary="pad ring">
656
      A circular interaction area, such as the touch ring on the Wacom Intuos
657
      Pro series tablets.
658

659
      Events on a ring are logically grouped by the wl_tablet_pad_ring.frame
660
      event.
661
    </description>
662

663
    <request name="set_feedback">
664
      <description summary="set compositor feedback">
665
	Request that the compositor use the provided feedback string
666
	associated with this ring. This request should be issued immediately
667
	after a wp_tablet_pad_group.mode_switch event from the corresponding
668
	group is received, or whenever the ring is mapped to a different
669
	action. See wp_tablet_pad_group.mode_switch for more details.
670

671
	Clients are encouraged to provide context-aware descriptions for
672
	the actions associated with the ring; compositors may use this
673
	information to offer visual feedback about the button layout
674
	(eg. on-screen displays).
675

676
	The provided string 'description' is a UTF-8 encoded string to be
677
	associated with this ring, and is considered user-visible; general
678
	internationalization rules apply.
679

680
	The serial argument will be that of the last
681
	wp_tablet_pad_group.mode_switch event received for the group of this
682
	ring. Requests providing other serials than the most recent one will be
683
	ignored.
684
      </description>
685
      <arg name="description" type="string" summary="ring description"/>
686
      <arg name="serial" type="uint" summary="serial of the mode switch event"/>
687
    </request>
688

689
    <request name="destroy" type="destructor">
690
      <description summary="destroy the ring object">
691
	This destroys the client's resource for this ring object.
692
      </description>
693
    </request>
694

695
    <enum name="source">
696
      <description summary="ring axis source">
697
	Describes the source types for ring events. This indicates to the
698
	client how a ring event was physically generated; a client may
699
	adjust the user interface accordingly. For example, events
700
	from a "finger" source may trigger kinetic scrolling.
701
      </description>
702
      <entry name="finger" value="1" summary="finger"/>
703
    </enum>
704

705
    <event name="source">
706
      <description summary="ring event source">
707
	Source information for ring events.
708

709
	This event does not occur on its own. It is sent before a
710
	wp_tablet_pad_ring.frame event and carries the source information
711
	for all events within that frame.
712

713
	The source specifies how this event was generated. If the source is
714
	wp_tablet_pad_ring.source.finger, a wp_tablet_pad_ring.stop event
715
	will be sent when the user lifts the finger off the device.
716

717
	This event is optional. If the source is unknown for an interaction,
718
	no event is sent.
719
      </description>
720
      <arg name="source" type="uint" enum="source" summary="the event source"/>
721
    </event>
722

723
    <event name="angle">
724
      <description summary="angle changed">
725
	Sent whenever the angle on a ring changes.
726

727
	The angle is provided in degrees clockwise from the logical
728
	north of the ring in the pad's current rotation.
729
      </description>
730
      <arg name="degrees" type="fixed" summary="the current angle in degrees"/>
731
    </event>
732

733
    <event name="stop">
734
      <description summary="interaction stopped">
735
	Stop notification for ring events.
736

737
	For some wp_tablet_pad_ring.source types, a wp_tablet_pad_ring.stop
738
	event is sent to notify a client that the interaction with the ring
739
	has terminated. This enables the client to implement kinetic scrolling.
740
	See the wp_tablet_pad_ring.source documentation for information on
741
	when this event may be generated.
742

743
	Any wp_tablet_pad_ring.angle events with the same source after this
744
	event should be considered as the start of a new interaction.
745
      </description>
746
    </event>
747

748
    <event name="frame">
749
      <description summary="end of a ring event sequence">
750
	Indicates the end of a set of ring events that logically belong
751
	together. A client is expected to accumulate the data in all events
752
	within the frame before proceeding.
753

754
	All wp_tablet_pad_ring events before a wp_tablet_pad_ring.frame event belong
755
	logically together. For example, on termination of a finger interaction
756
	on a ring the compositor will send a wp_tablet_pad_ring.source event,
757
	a wp_tablet_pad_ring.stop event and a wp_tablet_pad_ring.frame event.
758

759
	A wp_tablet_pad_ring.frame event is sent for every logical event
760
	group, even if the group only contains a single wp_tablet_pad_ring
761
	event. Specifically, a client may get a sequence: angle, frame,
762
	angle, frame, etc.
763
      </description>
764
      <arg name="time" type="uint" summary="timestamp with millisecond granularity"/>
765
    </event>
766
  </interface>
767

768
  <interface name="zwp_tablet_pad_strip_v2" version="1">
769
    <description summary="pad strip">
770
      A linear interaction area, such as the strips found in Wacom Cintiq
771
      models.
772

773
      Events on a strip are logically grouped by the wl_tablet_pad_strip.frame
774
      event.
775
    </description>
776

777
    <request name="set_feedback">
778
      <description summary="set compositor feedback">
779
	Requests the compositor to use the provided feedback string
780
	associated with this strip. This request should be issued immediately
781
	after a wp_tablet_pad_group.mode_switch event from the corresponding
782
	group is received, or whenever the strip is mapped to a different
783
	action. See wp_tablet_pad_group.mode_switch for more details.
784

785
	Clients are encouraged to provide context-aware descriptions for
786
	the actions associated with the strip, and compositors may use this
787
	information to offer visual feedback about the button layout
788
	(eg. on-screen displays).
789

790
	The provided string 'description' is a UTF-8 encoded string to be
791
	associated with this ring, and is considered user-visible; general
792
	internationalization rules apply.
793

794
	The serial argument will be that of the last
795
	wp_tablet_pad_group.mode_switch event received for the group of this
796
	strip. Requests providing other serials than the most recent one will be
797
	ignored.
798
      </description>
799
      <arg name="description" type="string" summary="strip description"/>
800
      <arg name="serial" type="uint" summary="serial of the mode switch event"/>
801
    </request>
802

803
    <request name="destroy" type="destructor">
804
      <description summary="destroy the strip object">
805
	This destroys the client's resource for this strip object.
806
      </description>
807
    </request>
808

809
    <enum name="source">
810
      <description summary="strip axis source">
811
	Describes the source types for strip events. This indicates to the
812
	client how a strip event was physically generated; a client may
813
	adjust the user interface accordingly. For example, events
814
	from a "finger" source may trigger kinetic scrolling.
815
      </description>
816
      <entry name="finger" value="1" summary="finger"/>
817
    </enum>
818

819
    <event name="source">
820
      <description summary="strip event source">
821
	Source information for strip events.
822

823
	This event does not occur on its own. It is sent before a
824
	wp_tablet_pad_strip.frame event and carries the source information
825
	for all events within that frame.
826

827
	The source specifies how this event was generated. If the source is
828
	wp_tablet_pad_strip.source.finger, a wp_tablet_pad_strip.stop event
829
	will be sent when the user lifts their finger off the device.
830

831
	This event is optional. If the source is unknown for an interaction,
832
	no event is sent.
833
      </description>
834
      <arg name="source" type="uint" enum="source" summary="the event source"/>
835
    </event>
836

837
    <event name="position">
838
      <description summary="position changed">
839
	Sent whenever the position on a strip changes.
840

841
	The position is normalized to a range of [0, 65535], the 0-value
842
	represents the top-most and/or left-most position of the strip in
843
	the pad's current rotation.
844
      </description>
845
      <arg name="position" type="uint" summary="the current position"/>
846
    </event>
847

848
    <event name="stop">
849
      <description summary="interaction stopped">
850
	Stop notification for strip events.
851

852
	For some wp_tablet_pad_strip.source types, a wp_tablet_pad_strip.stop
853
	event is sent to notify a client that the interaction with the strip
854
	has terminated. This enables the client to implement kinetic
855
	scrolling. See the wp_tablet_pad_strip.source documentation for
856
	information on when this event may be generated.
857

858
	Any wp_tablet_pad_strip.position events with the same source after this
859
	event should be considered as the start of a new interaction.
860
      </description>
861
    </event>
862

863
    <event name="frame">
864
      <description summary="end of a strip event sequence">
865
	Indicates the end of a set of events that represent one logical
866
	hardware strip event. A client is expected to accumulate the data
867
	in all events within the frame before proceeding.
868

869
	All wp_tablet_pad_strip events before a wp_tablet_pad_strip.frame event belong
870
	logically together. For example, on termination of a finger interaction
871
	on a strip the compositor will send a wp_tablet_pad_strip.source event,
872
	a wp_tablet_pad_strip.stop event and a wp_tablet_pad_strip.frame
873
	event.
874

875
	A wp_tablet_pad_strip.frame event is sent for every logical event
876
	group, even if the group only contains a single wp_tablet_pad_strip
877
	event. Specifically, a client may get a sequence: position, frame,
878
	position, frame, etc.
879
      </description>
880
      <arg name="time" type="uint" summary="timestamp with millisecond granularity"/>
881
    </event>
882
  </interface>
883

884
  <interface name="zwp_tablet_pad_group_v2" version="1">
885
    <description summary="a set of buttons, rings and strips">
886
      A pad group describes a distinct (sub)set of buttons, rings and strips
887
      present in the tablet. The criteria of this grouping is usually positional,
888
      eg. if a tablet has buttons on the left and right side, 2 groups will be
889
      presented. The physical arrangement of groups is undisclosed and may
890
      change on the fly.
891

892
      Pad groups will announce their features during pad initialization. Between
893
      the corresponding wp_tablet_pad.group event and wp_tablet_pad_group.done, the
894
      pad group will announce the buttons, rings and strips contained in it,
895
      plus the number of supported modes.
896

897
      Modes are a mechanism to allow multiple groups of actions for every element
898
      in the pad group. The number of groups and available modes in each is
899
      persistent across device plugs. The current mode is user-switchable, it
900
      will be announced through the wp_tablet_pad_group.mode_switch event both
901
      whenever it is switched, and after wp_tablet_pad.enter.
902

903
      The current mode logically applies to all elements in the pad group,
904
      although it is at clients' discretion whether to actually perform different
905
      actions, and/or issue the respective .set_feedback requests to notify the
906
      compositor. See the wp_tablet_pad_group.mode_switch event for more details.
907
    </description>
908

909
    <request name="destroy" type="destructor">
910
      <description summary="destroy the pad object">
911
	Destroy the wp_tablet_pad_group object. Objects created from this object
912
	are unaffected and should be destroyed separately.
913
      </description>
914
    </request>
915

916
    <event name="buttons">
917
      <description summary="buttons announced">
918
	Sent on wp_tablet_pad_group initialization to announce the available
919
	buttons in the group. Button indices start at 0, a button may only be
920
	in one group at a time.
921

922
	This event is first sent in the initial burst of events before the
923
	wp_tablet_pad_group.done event.
924

925
	Some buttons are reserved by the compositor. These buttons may not be
926
	assigned to any wp_tablet_pad_group. Compositors may broadcast this
927
	event in the case of changes to the mapping of these reserved buttons.
928
	If the compositor happens to reserve all buttons in a group, this event
929
	will be sent with an empty array.
930
      </description>
931
      <arg name="buttons" type="array" summary="buttons in this group"/>
932
    </event>
933

934
    <event name="ring">
935
      <description summary="ring announced">
936
	Sent on wp_tablet_pad_group initialization to announce available rings.
937
	One event is sent for each ring available on this pad group.
938

939
	This event is sent in the initial burst of events before the
940
	wp_tablet_pad_group.done event.
941
      </description>
942
      <arg name="ring" type="new_id" interface="zwp_tablet_pad_ring_v2"/>
943
    </event>
944

945
    <event name="strip">
946
      <description summary="strip announced">
947
	Sent on wp_tablet_pad initialization to announce available strips.
948
	One event is sent for each strip available on this pad group.
949

950
	This event is sent in the initial burst of events before the
951
	wp_tablet_pad_group.done event.
952
      </description>
953
      <arg name="strip" type="new_id" interface="zwp_tablet_pad_strip_v2"/>
954
    </event>
955

956
    <event name="modes">
957
      <description summary="mode-switch ability announced">
958
	Sent on wp_tablet_pad_group initialization to announce that the pad
959
	group may switch between modes. A client may use a mode to store a
960
	specific configuration for buttons, rings and strips and use the
961
	wl_tablet_pad_group.mode_switch event to toggle between these
962
	configurations. Mode indices start at 0.
963

964
	Switching modes is compositor-dependent. See the
965
	wp_tablet_pad_group.mode_switch event for more details.
966

967
	This event is sent in the initial burst of events before the
968
	wp_tablet_pad_group.done event. This event is only sent when more than
969
	more than one mode is available.
970
      </description>
971
      <arg name="modes" type="uint" summary="the number of modes"/>
972
    </event>
973

974
    <event name="done">
975
      <description summary="tablet group description events sequence complete">
976
	This event is sent immediately to signal the end of the initial
977
	burst of descriptive events. A client may consider the static
978
	description of the tablet to be complete and finalize initialization
979
	of the tablet group.
980
      </description>
981
    </event>
982

983
    <event name="mode_switch">
984
      <description summary="mode switch event">
985
	Notification that the mode was switched.
986

987
	A mode applies to all buttons, rings and strips in a group
988
	simultaneously, but a client is not required to assign different actions
989
	for each mode. For example, a client may have mode-specific button
990
	mappings but map the ring to vertical scrolling in all modes. Mode
991
	indices start at 0.
992

993
	Switching modes is compositor-dependent. The compositor may provide
994
	visual cues to the client about the mode, e.g. by toggling LEDs on
995
	the tablet device. Mode-switching may be software-controlled or
996
	controlled by one or more physical buttons. For example, on a Wacom
997
	Intuos Pro, the button inside the ring may be assigned to switch
998
	between modes.
999

1000
	The compositor will also send this event after wp_tablet_pad.enter on
1001
	each group in order to notify of the current mode. Groups that only
1002
	feature one mode will use mode=0 when emitting this event.
1003

1004
	If a button action in the new mode differs from the action in the
1005
	previous mode, the client should immediately issue a
1006
	wp_tablet_pad.set_feedback request for each changed button.
1007

1008
	If a ring or strip action in the new mode differs from the action
1009
	in the previous mode, the client should immediately issue a
1010
	wp_tablet_ring.set_feedback or wp_tablet_strip.set_feedback request
1011
	for each changed ring or strip.
1012
      </description>
1013
      <arg name="time" type="uint" summary="the time of the event with millisecond granularity"/>
1014
      <arg name="serial" type="uint"/>
1015
      <arg name="mode" type="uint" summary="the new mode of the pad"/>
1016
    </event>
1017
  </interface>
1018

1019
  <interface name="zwp_tablet_pad_v2" version="1">
1020
    <description summary="a set of buttons, rings and strips">
1021
      A pad device is a set of buttons, rings and strips
1022
      usually physically present on the tablet device itself. Some
1023
      exceptions exist where the pad device is physically detached, e.g. the
1024
      Wacom ExpressKey Remote.
1025

1026
      Pad devices have no axes that control the cursor and are generally
1027
      auxiliary devices to the tool devices used on the tablet surface.
1028

1029
      A pad device has a number of static characteristics, e.g. the number
1030
      of rings. These capabilities are sent in an event sequence after the
1031
      wp_tablet_seat.pad_added event before any actual events from this pad.
1032
      This initial event sequence is terminated by a wp_tablet_pad.done
1033
      event.
1034

1035
      All pad features (buttons, rings and strips) are logically divided into
1036
      groups and all pads have at least one group. The available groups are
1037
      notified through the wp_tablet_pad.group event; the compositor will
1038
      emit one event per group before emitting wp_tablet_pad.done.
1039

1040
      Groups may have multiple modes. Modes allow clients to map multiple
1041
      actions to a single pad feature. Only one mode can be active per group,
1042
      although different groups may have different active modes.
1043
    </description>
1044

1045
    <request name="set_feedback">
1046
      <description summary="set compositor feedback">
1047
	Requests the compositor to use the provided feedback string
1048
	associated with this button. This request should be issued immediately
1049
	after a wp_tablet_pad_group.mode_switch event from the corresponding
1050
	group is received, or whenever a button is mapped to a different
1051
	action. See wp_tablet_pad_group.mode_switch for more details.
1052

1053
	Clients are encouraged to provide context-aware descriptions for
1054
	the actions associated with each button, and compositors may use
1055
	this information to offer visual feedback on the button layout
1056
	(e.g. on-screen displays).
1057

1058
	Button indices start at 0. Setting the feedback string on a button
1059
	that is reserved by the compositor (i.e. not belonging to any
1060
	wp_tablet_pad_group) does not generate an error but the compositor
1061
	is free to ignore the request.
1062

1063
	The provided string 'description' is a UTF-8 encoded string to be
1064
	associated with this ring, and is considered user-visible; general
1065
	internationalization rules apply.
1066

1067
	The serial argument will be that of the last
1068
	wp_tablet_pad_group.mode_switch event received for the group of this
1069
	button. Requests providing other serials than the most recent one will
1070
	be ignored.
1071
      </description>
1072
      <arg name="button" type="uint" summary="button index"/>
1073
      <arg name="description" type="string" summary="button description"/>
1074
      <arg name="serial" type="uint" summary="serial of the mode switch event"/>
1075
    </request>
1076

1077
    <request name="destroy" type="destructor">
1078
      <description summary="destroy the pad object">
1079
	Destroy the wp_tablet_pad object. Objects created from this object
1080
	are unaffected and should be destroyed separately.
1081
      </description>
1082
    </request>
1083

1084
    <event name="group">
1085
      <description summary="group announced">
1086
	Sent on wp_tablet_pad initialization to announce available groups.
1087
	One event is sent for each pad group available.
1088

1089
	This event is sent in the initial burst of events before the
1090
	wp_tablet_pad.done event. At least one group will be announced.
1091
      </description>
1092
      <arg name="pad_group" type="new_id" interface="zwp_tablet_pad_group_v2"/>
1093
    </event>
1094

1095
    <event name="path">
1096
      <description summary="path to the device">
1097
	A system-specific device path that indicates which device is behind
1098
	this wp_tablet_pad. This information may be used to gather additional
1099
	information about the device, e.g. through libwacom.
1100

1101
	The format of the path is unspecified, it may be a device node, a
1102
	sysfs path, or some other identifier. It is up to the client to
1103
	identify the string provided.
1104

1105
	This event is sent in the initial burst of events before the
1106
	wp_tablet_pad.done event.
1107
      </description>
1108
      <arg name="path" type="string" summary="path to local device"/>
1109
    </event>
1110

1111
    <event name="buttons">
1112
      <description summary="buttons announced">
1113
	Sent on wp_tablet_pad initialization to announce the available
1114
	buttons.
1115

1116
	This event is sent in the initial burst of events before the
1117
	wp_tablet_pad.done event. This event is only sent when at least one
1118
	button is available.
1119
      </description>
1120
      <arg name="buttons" type="uint" summary="the number of buttons"/>
1121
    </event>
1122

1123
    <event name="done">
1124
      <description summary="pad description event sequence complete">
1125
	This event signals the end of the initial burst of descriptive
1126
	events. A client may consider the static description of the pad to
1127
	be complete and finalize initialization of the pad.
1128
      </description>
1129
    </event>
1130

1131
    <enum name="button_state">
1132
      <description summary="physical button state">
1133
	Describes the physical state of a button that caused the button
1134
	event.
1135
      </description>
1136
      <entry name="released" value="0" summary="the button is not pressed"/>
1137
      <entry name="pressed" value="1" summary="the button is pressed"/>
1138
    </enum>
1139

1140
    <event name="button">
1141
      <description summary="physical button state">
1142
	Sent whenever the physical state of a button changes.
1143
      </description>
1144
      <arg name="time" type="uint" summary="the time of the event with millisecond granularity"/>
1145
      <arg name="button" type="uint" summary="the index of the button that changed state"/>
1146
      <arg name="state" type="uint" enum="button_state"/>
1147
    </event>
1148

1149
    <event name="enter">
1150
      <description summary="enter event">
1151
	Notification that this pad is focused on the specified surface.
1152
      </description>
1153
      <arg name="serial" type="uint" summary="serial number of the enter event"/>
1154
      <arg name="tablet" type="object" interface="zwp_tablet_v2" summary="the tablet the pad is attached to"/>
1155
      <arg name="surface" type="object" interface="wl_surface" summary="surface the pad is focused on"/>
1156
    </event>
1157

1158
    <event name="leave">
1159
      <description summary="leave event">
1160
	Notification that this pad is no longer focused on the specified
1161
	surface.
1162
      </description>
1163
      <arg name="serial" type="uint" summary="serial number of the leave event"/>
1164
      <arg name="surface" type="object" interface="wl_surface" summary="surface the pad is no longer focused on"/>
1165
    </event>
1166

1167
    <event name="removed">
1168
      <description summary="pad removed event">
1169
	Sent when the pad has been removed from the system. When a tablet
1170
	is removed its pad(s) will be removed too.
1171

1172
	When this event is received, the client must destroy all rings, strips
1173
	and groups that were offered by this pad, and issue wp_tablet_pad.destroy
1174
	the pad itself.
1175
      </description>
1176
    </event>
1177
  </interface>
1178
</protocol>
1179