wdisplays/protocol/wlr-output-management-unstable-v1.xml

<?xml version="1.0" encoding="UTF-8"?>
<protocol name="wlr_output_management_unstable_v1">
  <copyright>
    Copyright © 2019 Purism SPC

    Permission to use, copy, modify, distribute, and sell this
    software and its documentation for any purpose is hereby granted
    without fee, provided that the above copyright notice appear in
    all copies and that both that copyright notice and this permission
    notice appear in supporting documentation, and that the name of
    the copyright holders not be used in advertising or publicity
    pertaining to distribution of the software without specific,
    written prior permission.  The copyright holders make no
    representations about the suitability of this software for any
    purpose.  It is provided "as is" without express or implied
    warranty.

    THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
    SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
    FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
    SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
    AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
    ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
    THIS SOFTWARE.
  </copyright>

  <description summary="protocol to configure output devices">
    This protocol exposes interfaces to obtain and modify output device
    configuration.

    Warning! The protocol described in this file is experimental and
    backward incompatible changes may be made. Backward compatible changes
    may be added together with the corresponding interface version bump.
    Backward incompatible changes are done by bumping the version number in
    the protocol and interface names and resetting the interface version.
    Once the protocol is to be declared stable, the 'z' prefix and the
    version number in the protocol and interface names are removed and the
    interface version number is reset.
  </description>

  <interface name="zwlr_output_manager_v1" version="1">
    <description summary="output device configuration manager">
      This interface is a manager that allows reading and writing the current
      output device configuration.

      Output devices that display pixels (e.g. a physical monitor or a virtual
      output in a window) are represented as heads. Heads cannot be created nor
      destroyed by the client, but they can be enabled or disabled and their
      properties can be changed. Each head may have one or more available modes.

      Whenever a head appears (e.g. a monitor is plugged in), it will be
      advertised via the head event. Immediately after the output manager is
      bound, all current heads are advertised.

      Whenever a head's properties change, the relevant wlr_output_head events
      will be sent. Not all head properties will be sent: only properties that
      have changed need to.

      Whenever a head disappears (e.g. a monitor is unplugged), a
      wlr_output_head.finished event will be sent.

      After one or more heads appear, change or disappear, the done event will
      be sent. It carries a serial which can be used in a create_configuration
      request to update heads properties.

      The information obtained from this protocol should only be used for output
      configuration purposes. This protocol is not designed to be a generic
      output property advertisement protocol for regular clients. Instead,
      protocols such as xdg-output should be used.
    </description>

    <event name="head">
      <description summary="introduce a new head">
        This event introduces a new head. This happens whenever a new head
        appears (e.g. a monitor is plugged in) or after the output manager is
        bound.
      </description>
      <arg name="head" type="new_id" interface="zwlr_output_head_v1"/>
    </event>

    <event name="done">
      <description summary="sent all information about current configuration">
        This event is sent after all information has been sent after binding to
        the output manager object and after any subsequent changes. This applies
        to child head and mode objects as well. In other words, this event is
        sent whenever a head or mode is created or destroyed and whenever one of
        their properties has been changed. Not all state is re-sent each time
        the current configuration changes: only the actual changes are sent.

        This allows changes to the output configuration to be seen as atomic,
        even if they happen via multiple events.

        A serial is sent to be used in a future create_configuration request.
      </description>
      <arg name="serial" type="uint" summary="current configuration serial"/>
    </event>

    <request name="create_configuration">
      <description summary="create a new output configuration object">
        Create a new output configuration object. This allows to update head
        properties.
      </description>
      <arg name="id" type="new_id" interface="zwlr_output_configuration_v1"/>
      <arg name="serial" type="uint"/>
    </request>

    <request name="stop">
      <description summary="stop sending events">
        Indicates the client no longer wishes to receive events for output
        configuration changes. However the compositor may emit further events,
        until the finished event is emitted.

        The client must not send any more requests after this one.
      </description>
    </request>

    <event name="finished">
      <description summary="the compositor has finished with the manager">
        This event indicates that the compositor is done sending manager events.
        The compositor will destroy the object immediately after sending this
        event, so it will become invalid and the client should release any
        resources associated with it.
      </description>
    </event>
  </interface>

  <interface name="zwlr_output_head_v1" version="1">
    <description summary="output device">
      A head is an output device. The difference between a wl_output object and
      a head is that heads are advertised even if they are turned off. A head
      object only advertises properties and cannot be used directly to change
      them.

      A head has some read-only properties: modes, name, description and
      physical_size. These cannot be changed by clients.

      Other properties can be updated via a wlr_output_configuration object.

      Properties sent via this interface are applied atomically via the
      wlr_output_manager.done event. No guarantees are made regarding the order
      in which properties are sent.
    </description>

    <event name="name">
      <description summary="head name">
        This event describes the head name.

        The naming convention is compositor defined, but limited to alphanumeric
        characters and dashes (-). Each name is unique among all wlr_output_head
        objects, but if a wlr_output_head object is destroyed the same name may
        be reused later. The names will also remain consistent across sessions
        with the same hardware and software configuration.

        Examples of names include 'HDMI-A-1', 'WL-1', 'X11-1', etc. However, do
        not assume that the name is a reflection of an underlying DRM
        connector, X11 connection, etc.

        If the compositor implements the xdg-output protocol and this head is
        enabled, the xdg_output.name event must report the same name.

        The name event is sent after a wlr_output_head object is created. This
        event is only sent once per object, and the name does not change over
        the lifetime of the wlr_output_head object.
      </description>
      <arg name="name" type="string"/>
    </event>

    <event name="description">
      <description summary="head description">
        This event describes a human-readable description of the head.

        The description is a UTF-8 string with no convention defined for its
        contents. Examples might include 'Foocorp 11" Display' or 'Virtual X11
        output via :1'. However, do not assume that the name is a reflection of
        the make, model, serial of the underlying DRM connector or the display
        name of the underlying X11 connection, etc.

        If the compositor implements xdg-output and this head is enabled,
        the xdg_output.description must report the same description.

        The description event is sent after a wlr_output_head object is created.
        This event is only sent once per object, and the description does not
        change over the lifetime of the wlr_output_head object.
      </description>
      <arg name="description" type="string"/>
    </event>

    <event name="physical_size">
      <description summary="head physical size">
        This event describes the physical size of the head. This event is only
        sent if the head has a physical size (e.g. is not a projector or a
        virtual device).
      </description>
      <arg name="width" type="int" summary="width in millimeters of the output"/>
      <arg name="height" type="int" summary="height in millimeters of the output"/>
    </event>

    <event name="mode">
      <description summary="introduce a mode">
        This event introduces a mode for this head. It is sent once per
        supported mode.
      </description>
      <arg name="mode" type="new_id" interface="zwlr_output_mode_v1"/>
    </event>

    <event name="enabled">
      <description summary="head is enabled or disabled">
        This event describes whether the head is enabled. A disabled head is not
        mapped to a region of the global compositor space.

        When a head is disabled, some properties (current_mode, position,
        transform and scale) are irrelevant.
      </description>
      <arg name="enabled" type="int" summary="zero if disabled, non-zero if enabled"/>
    </event>

    <event name="current_mode">
      <description summary="current mode">
        This event describes the mode currently in use for this head. It is only
        sent if the output is enabled.
      </description>
      <arg name="mode" type="object" interface="zwlr_output_mode_v1"/>
    </event>

    <event name="position">
      <description summary="current position">
        This events describes the position of the head in the global compositor
        space. It is only sent if the output is enabled.
      </description>
      <arg name="x" type="int"
        summary="x position within the global compositor space"/>
      <arg name="y" type="int"
        summary="y position within the global compositor space"/>
    </event>

    <event name="transform">
      <description summary="current transformation">
        This event describes the transformation currently applied to the head.
        It is only sent if the output is enabled.
      </description>
      <arg name="transform" type="int" enum="wl_output.transform"/>
    </event>

    <event name="scale">
      <description summary="current scale">
        This events describes the scale of the head in the global compositor
        space. It is only sent if the output is enabled.
      </description>
      <arg name="scale" type="fixed"/>
    </event>

    <event name="finished">
      <description summary="the head has been destroyed">
        The compositor will destroy the object immediately after sending this
        event, so it will become invalid and the client should release any
        resources associated with it.
      </description>
    </event>
  </interface>

  <interface name="zwlr_output_mode_v1" version="1">
    <description summary="output mode">
      This object describes an output mode.

      Some heads don't support output modes, in which case modes won't be
      advertised.

      Properties sent via this interface are applied atomically via the
      wlr_output_manager.done event. No guarantees are made regarding the order
      in which properties are sent.
    </description>

    <event name="size">
      <description summary="mode size">
        This event describes the mode size. The size is given in physical
        hardware units of the output device. This is not necessarily the same as
        the output size in the global compositor space. For instance, the output
        may be scaled or transformed.
      </description>
      <arg name="width" type="int" summary="width of the mode in hardware units"/>
      <arg name="height" type="int" summary="height of the mode in hardware units"/>
    </event>

    <event name="refresh">
      <description summary="mode refresh rate">
        This event describes the mode's fixed vertical refresh rate. It is only
        sent if the mode has a fixed refresh rate.
      </description>
      <arg name="refresh" type="int" summary="vertical refresh rate in mHz"/>
    </event>

    <event name="preferred">
      <description summary="mode is preferred">
        This event advertises this mode as preferred.
      </description>
    </event>

    <event name="finished">
      <description summary="the mode has been destroyed">
        The compositor will destroy the object immediately after sending this
        event, so it will become invalid and the client should release any
        resources associated with it.
      </description>
    </event>
  </interface>

  <interface name="zwlr_output_configuration_v1" version="1">
    <description summary="output configuration">
      This object is used by the client to describe a full output configuration.

      First, the client needs to setup the output configuration. Each head can
      be either enabled (and configured) or disabled. It is a protocol error to
      send two enable_head or disable_head requests with the same head. It is a
      protocol error to omit a head in a configuration.

      Then, the client can apply or test the configuration. The compositor will
      then reply with a succeeded, failed or cancelled event. Finally the client
      should destroy the configuration object.
    </description>

    <enum name="error">
      <entry name="already_configured_head" value="1"
        summary="head has been configured twice"/>
      <entry name="unconfigured_head" value="2"
        summary="head has not been configured"/>
      <entry name="already_used" value="3"
        summary="request sent after configuration has been applied or tested"/>
    </enum>

    <request name="enable_head">
      <description summary="enable and configure a head">
        Enable a head. This request creates a head configuration object that can
        be used to change the head's properties.
      </description>
      <arg name="id" type="new_id" interface="zwlr_output_configuration_head_v1"
        summary="a new object to configure the head"/>
      <arg name="head" type="object" interface="zwlr_output_head_v1"
        summary="the head to be enabled"/>
    </request>

    <request name="disable_head">
      <description summary="disable a head">
        Disable a head.
      </description>
      <arg name="head" type="object" interface="zwlr_output_head_v1"
        summary="the head to be disabled"/>
    </request>

    <request name="apply">
      <description summary="apply the configuration">
        Apply the new output configuration.

        In case the configuration is successfully applied, there is no guarantee
        that the new output state matches completely the requested
        configuration. For instance, a compositor might round the scale if it
        doesn't support fractional scaling.

        After this request has been sent, the compositor must respond with an
        succeeded, failed or cancelled event. Sending a request that isn't the
        destructor is a protocol error.
      </description>
    </request>

    <request name="test">
      <description summary="test the configuration">
        Test the new output configuration. The configuration won't be applied,
        but will only be validated.

        Even if the compositor succeeds to test a configuration, applying it may
        fail.

        After this request has been sent, the compositor must respond with an
        succeeded, failed or cancelled event. Sending a request that isn't the
        destructor is a protocol error.
      </description>
    </request>

    <event name="succeeded">
      <description summary="configuration changes succeeded">
        Sent after the compositor has successfully applied the changes or
        tested them.

        Upon receiving this event, the client should destroy this object.

        If the current configuration has changed, events to describe the changes
        will be sent followed by a wlr_output_manager.done event.
      </description>
    </event>

    <event name="failed">
      <description summary="configuration changes failed">
        Sent if the compositor rejects the changes or failed to apply them. The
        compositor should revert any changes made by the apply request that
        triggered this event.

        Upon receiving this event, the client should destroy this object.
      </description>
    </event>

    <event name="cancelled">
      <description summary="configuration has been cancelled">
        Sent if the compositor cancels the configuration because the state of an
        output changed and the client has outdated information (e.g. after an
        output has been hotplugged).

        The client can create a new configuration with a newer serial and try
        again.

        Upon receiving this event, the client should destroy this object.
      </description>
    </event>

    <request name="destroy" type="destructor">
      <description summary="destroy the output configuration">
        Using this request a client can tell the compositor that it is not going
        to use the configuration object anymore. Any changes to the outputs
        that have not been applied will be discarded.

        This request also destroys wlr_output_configuration_head objects created
        via this object.
      </description>
    </request>
  </interface>

  <interface name="zwlr_output_configuration_head_v1" version="1">
    <description summary="head configuration">
      This object is used by the client to update a single head's configuration.

      It is a protocol error to set the same property twice.
    </description>

    <enum name="error">
      <entry name="already_set" value="1" summary="property has already been set"/>
      <entry name="invalid_mode" value="2" summary="mode doesn't belong to head"/>
      <entry name="invalid_custom_mode" value="3" summary="mode is invalid"/>
      <entry name="invalid_transform" value="4" summary="transform value outside enum"/>
      <entry name="invalid_scale" value="5" summary="scale negative or zero"/>
    </enum>

    <request name="set_mode">
      <description summary="set the mode">
        This request sets the head's mode.
      </description>
      <arg name="mode" type="object" interface="zwlr_output_mode_v1"/>
    </request>

    <request name="set_custom_mode">
      <description summary="set a custom mode">
        This request assigns a custom mode to the head. The size is given in
        physical hardware units of the output device. If set to zero, the
        refresh rate is unspecified.

        It is a protocol error to set both a mode and a custom mode.
      </description>
      <arg name="width" type="int" summary="width of the mode in hardware units"/>
      <arg name="height" type="int" summary="height of the mode in hardware units"/>
      <arg name="refresh" type="int" summary="vertical refresh rate in mHz or zero"/>
    </request>

    <request name="set_position">
      <description summary="set the position">
        This request sets the head's position in the global compositor space.
      </description>
      <arg name="x" type="int" summary="x position in the global compositor space"/>
      <arg name="y" type="int" summary="y position in the global compositor space"/>
    </request>

    <request name="set_transform">
      <description summary="set the transform">
        This request sets the head's transform.
      </description>
      <arg name="transform" type="int" enum="wl_output.transform"/>
    </request>

    <request name="set_scale">
      <description summary="set the scale">
        This request sets the head's scale.
      </description>
      <arg name="scale" type="fixed"/>
    </request>
  </interface>
</protocol>