river/protocol/river-layout-v3.xml
Leon Henrik Plickat 844ffce037
river-layout: add user_command_tags event
It is not guaranteed that the next layout_demand event after a user_command
event has the same active tags (for example when there are no views visible).
As an example, a user could trigger a user_command while no views are visible,
then switch to a different tag set which has active views. The active tags of
the previous layout_demand may also be different.

Therefore it is impossible to correctly implement a layout generator which has
user commands apply only to the currently active tag set, which is solved by
this patch.
2022-08-16 13:40:07 +02:00

197 lines
9.2 KiB
XML

<?xml version="1.0" encoding="UTF-8"?>
<protocol name="river_layout_v3">
<copyright>
Copyright 2020-2021 The River Developers
Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, 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="let clients propose view positions and dimensions">
This protocol specifies a way for clients to propose arbitrary positions
and dimensions for a set of views on a specific output of a compositor
through the river_layout_v3 object.
Layouts are a strictly linear list of views, the position and dimensions
of which are supplied by the client. Any complex underlying data structure
a client may use when generating the layout is lost in transmission. This
is an intentional limitation.
Additionally, this protocol allows the compositor to deliver arbitrary
user-provided commands associated with a layout to clients. A client
may use these commands to implement runtime configuration/control, or
may ignore them entirely. How the user provides these commands to the
compositor is not specified by this protocol and left to compositor policy.
Warning! The protocol described in this file is currently in the
testing phase. Backward compatible changes may be added together with
the corresponding interface version bump. Backward incompatible changes
can only be done by creating a new major version of the extension.
</description>
<interface name="river_layout_manager_v3" version="2">
<description summary="manage river layout objects">
A global factory for river_layout_v3 objects.
</description>
<request name="destroy" type="destructor">
<description summary="destroy the river_layout_manager object">
This request indicates that the client will not use the
river_layout_manager object any more. Objects that have been created
through this instance are not affected.
</description>
</request>
<request name="get_layout">
<description summary="create a river_layout_v3 object">
This creates a new river_layout_v3 object for the given wl_output.
All layout related communication is done through this interface.
The namespace is used by the compositor to decide which river_layout_v3
object will receive layout demands for the output.
The namespace is required to be be unique per-output. Furthermore,
two separate clients may not share a namespace on separate outputs. If
these conditions are not upheld, the the namespace_in_use event will
be sent directly after creation of the river_layout_v3 object.
</description>
<arg name="id" type="new_id" interface="river_layout_v3"/>
<arg name="output" type="object" interface="wl_output"/>
<arg name="namespace" type="string" summary="namespace of the layout object"/>
</request>
</interface>
<interface name="river_layout_v3" version="2">
<description summary="receive and respond to layout demands">
This interface allows clients to receive layout demands from the
compositor for a specific output and subsequently propose positions and
dimensions of individual views.
</description>
<enum name="error">
<entry name="count_mismatch" value="0" summary="number of
proposed dimensions does not match number of views in layout"/>
<entry name="already_committed" value="1" summary="the layout demand with
the provided serial was already committed"/>
</enum>
<request name="destroy" type="destructor">
<description summary="destroy the river_layout_v3 object">
This request indicates that the client will not use the river_layout_v3
object any more.
</description>
</request>
<event name="namespace_in_use">
<description summary="the requested namespace is already in use">
After this event is sent, all requests aside from the destroy event
will be ignored by the server. If the client wishes to try again with
a different namespace they must create a new river_layout_v3 object.
</description>
</event>
<event name="layout_demand">
<description summary="the compositor requires a layout">
The compositor sends this event to inform the client that it requires a
layout for a set of views.
The usable width and height indicate the space in which the client
can safely position views without interfering with desktop widgets
such as panels.
The serial of this event is used to identify subsequent requests as
belonging to this layout demand. Beware that the client might need
to handle multiple layout demands at the same time.
The server will ignore responses to all but the most recent layout
demand. Thus, clients are only required to respond to the most recent
layout_demand received. If a newer layout_demand is received before
the client has finished responding to an old demand, the client should
abort work on the old demand as any further work would be wasted.
</description>
<arg name="view_count" type="uint" summary="number of views in the layout"/>
<arg name="usable_width" type="uint" summary="width of the usable area"/>
<arg name="usable_height" type="uint" summary="height of the usable area"/>
<arg name="tags" type="uint" summary="tags of the output, 32-bit bitfield"/>
<arg name="serial" type="uint" summary="serial of the layout demand"/>
</event>
<request name="push_view_dimensions">
<description summary="propose dimensions of the next view">
This request proposes a size and position for a view in the layout demand
with matching serial.
A client must send this request for every view that is part of the
layout demand. The number of views in the layout is given by the
view_count argument of the layout_demand event. Pushing too many or
too few view dimensions is a protocol error.
The x and y coordinates are relative to the usable area of the output,
with (0,0) as the top left corner.
</description>
<arg name="x" type="int" summary="x coordinate of view"/>
<arg name="y" type="int" summary="y coordinate of view"/>
<arg name="width" type="uint" summary="width of view"/>
<arg name="height" type="uint" summary="height of view"/>
<arg name="serial" type="uint" summary="serial of layout demand"/>
</request>
<request name="commit">
<description summary="commit a layout">
This request indicates that the client is done pushing dimensions
and the compositor may apply the layout. This completes the layout
demand with matching serial, any other requests sent with the serial
are a protocol error.
The layout_name argument is a user-facing name or short description
of the layout that is being committed. The compositor may for example
display this on a status bar, though what exactly is done with it is
left to the compositor's discretion.
The compositor is free to use this proposed layout however it chooses,
including ignoring it.
</description>
<arg name="layout_name" type="string" summary="name of committed layout"/>
<arg name="serial" type="uint" summary="serial of layout demand"/>
</request>
<event name="user_command">
<description summary="a command sent by the user">
This event informs the client of a command sent to it by the user.
The semantic meaning of the command is left for the client to
decide. It is also free to ignore it entirely if it so chooses.
A layout_demand will be sent after this event if the compositor is
currently using this layout object to arrange the output.
If version 2 or higher of the river_layout_v3 object is bound, the
user_command_tags event is guaranteed to be sent directly before the
user_command event.
</description>
<arg name="command" type="string"/>
</event>
<event name="user_command_tags" since="2">
<description summary="a command sent by the user">
If version 2 or higher of the river_layout_v3 object is bound, this
event will be sent directly before every user_command event. This allows
layout generators to be aware of the active tags when a user command is
sent. This is necessary for generators wanting to keep settings on a
per-tag basis.
</description>
<arg name="tags" type="uint" summary="tags of the output, 32-bit bitfield"/>
</event>
</interface>
</protocol>