Provided by: python3-pywayland_0.4.18-2_amd64 
NAME
pywayland - pywayland Documentation
PyWayland provides Python bindings to the Wayland library, using pure Python by making
calls through the CFFI module. PyWayland supports Python >=3.6, including sufficiently
new versions of PyPy 3. This is currently a highly experimental package, and the usage is
likely to change between releases. Check back as development continues, contributions are
always welcome!
Check out the different sections below for information on installing and running
PyWayland. There is also information on running and developing from source (feedback and
contributions are always welcome on the issue tracker). Finally, the module documentation
is included.
DOCUMENTATION
Installation
To install PyWayland, you will need to have a base set of dependencies installed. This
should be all the configuration that is required to run the packaged version on PyPI. The
additional steps to build and install from source are outlined below.
If you have any problems with anything outlined here, feedback is greatly appreciated.
External Dependencies
In order to run PyWayland, you will need to have installed the Wayland libraries and
headers such that they can be found by CFFI. This can be done with the libwayland-dev apt
package; however, note that it is probably best to use the most recent version of Wayland
available from the Wayland releases site, and the pip package will try to track the most
recent version.
You will also need to have the Python headers installed and a version of GCC to compile
the cffi library. The headers are typically available through the python-dev package.
Optionally, you can have installed the wayland-protocols package, also available from the
Wayland releases page. The package uploaded to PyPI will already have these protocols
included, so this is only needed if you plan on installing from source.
Installing with pip
Once the external dependencies are in place you should just be able to run:
$ pip install pywayland
Any additional unfulfilled dependencies should be downloaded.
Installing from Source
You can download and run PyWayland from source, which will not only give you the latest
improvements and fixes, but will let you build the protocol files against a different
version than is available through pip (the version of Wayland the protocol is compiled
against is listed on the top of the PyPI page).
Getting the Source
You can download the most recent version of PyWayland from the git repository, or clone
the repository as:
$ git clone https://github.com/flacjacket/pywayland.git
Python Dependencies
PyWayland depends on a minimal set of dependencies. All Python version require cffi (to
perform Wayland library calls), which can be pip installed for non-PyPy installations.
Note that PyPy platforms ship with cffi.
Generating the Wayland Protocol
At this point, you have the base PyWayland module, which contains some core objects and
objects specific to client and server implementations. The client and server exchange
messages defined in the Wayland protocol, which is an XML file that ships with Wayland.
The scanner parses this XML file and generates the relevant objects.
If the Wayland protocol file is in the default location (/usr/share/wayland/wayland.xml)
or can be found with pkg-config, you should be able to build the protocol files without
any problems:
$ python -m pywayland.scanner
This will output the protocol files to the directory ./pywayland/protocol/. The input
file and the output directory can be set from the command line options, see python -m
pywayland.scanner -h for more information.
Running PyWayland inplace
Once the protocol files are created, you can generate the cffi module. Note: this is only
required if you want to run from the source in place. If the libwayland header files are
correctly installed, you will just need to run:
$ python pywayland/ffi_build.py
At this point, you should be able to use the PyWayland library. You can check that you
have everything installed correctly by running the associated test-suite (note that you
will also need pytest to run the tests). Simply run:
$ pytest
from the root directory.
Installing PyWayland
The package can be installed from source using typical setup.py mechanisms:
$ python setup.py install
Additional arguments can be used to automatically generate the Wayland protocols for the
standard Wayland package (which will fail if it cannot run) and the wayland-protocols
package (which will be attempted by default, but will not raise an error if it fails).
If you have any problems or have any feedback, please report back to the issue tracker,
contribution is always welcome, see Contributing.
Contributing
Build Status Build Coverage
Contributions of any form are always welcome, whether it is general feedback on the use of
PyWayland, bug reports, or pull requests. All development is done through GitHub.
If you wish to develop PyWayland, it is recommended that you follow the outline given in
Installing from Source. A few things to be aware of when writing code:
• Continuous integration testing in done with Travis, and tests are run against all
supported Python versions (currently 3.6+ and PyPy 3). You can check that your changes
pass locally by running py.test from the root directory (this requires installing ‐
pytest). Currently, the tests also run with nose, however, they may not always in the
future.
• Code coverage is assessed using Coveralls. Currently, coverage is fairly low, any work
to help this would be greatly appreciated.
• Code quality is assessed in the tests with ruff, be sure any new code meets Python
standards.
• Type annotations are included in much of the codebase and checked with mypy. Additional
checks using other type checkers are appreciated.
PyWayland Scanner
The PyWayland scanner parses the wayland.xml protocol definition file and outputs
interfaces with the events, requests, and enums defined by the protocol. See Scanner
Modules for details on the scanner implementation.
Command-line Invocation
If you have installed PyWayland, the scanner is placed in your path as
pywayland-scanner.py. By default, invoking the scanner reads in the XML file from
/usr/share/wayland/wayland.xml and outputs the protocol definitions to ./protocol/.
If you are running PyWayland from source, you can use the scanner in
./bin/pywayland-scanner.py. This file sets the path to the current source directory and
runs method used by the entry-point. Otherwise, this functions the same as above.
Script Invocation
In addition to the command-line use, you can use the scanner from within Python scripts.
This is done, for example, when installing or building the docs to ensure the protocol
modules are included in both. For details on invoking the scanner module, see Scanner.
Module Reference
Client Modules
The base set of objects used by Wayland clients. Users should only be directly creating
Display and EventQueue objects. The Proxy objects to interfaces should be returned by
making request calls.
Display
class pywayland.client.Display(name_or_fd: int | str | None = None)
Represents a connection to the compositor
A Display object represents a client connection to a Wayland compositor. The
connection and the corresponding Wayland object are created with Display.connect().
The display must be connected before it can be used. A connection is terminated
using Display.disconnect().
A Display is also used as the Proxy for the pywayland.protocol.wayland.WlDisplay
protocol object on the compositor side.
A Display object handles all the data sent from and to the compositor. When a
Proxy marshals a request, it will write its wire representation to the display's
write buffer. The data is sent to the compositor when the client calls flush().
Incoming data is handled in two steps: queueing and dispatching. In the queue step,
the data coming from the display fd is interpreted and added to a queue. On the
dispatch step, the handler for the incoming event set by the client on the
corresponding Proxy is called.
A Display has at least one event queue, called the default queue. Clients can
create additional event queues with Display.create_queue() and assign Proxy's to
it. Events occurring in a particular proxy are always queued in its assigned queue.
A client can ensure that a certain assumption, such as holding a lock or running
from a given thread, is true when a proxy event handler is called by assigning that
proxy to an event queue and making sure that this queue is only dispatched when the
assumption holds.
The default queue is dispatched by calling Display.dispatch(). This will dispatch
any events queued on the default queue and attempt to read from the display fd if
it's empty. Events read are then queued on the appropriate queues according to the
proxy assignment.
A user created queue is dispatched with Display.dispatch_queue(). This function
behaves exactly the same as Display.dispatch() but it dispatches given queue
instead of the default queue.
A real world example of event queue usage is Mesa's implementation of
glSwapBuffers() for the Wayland platform. This function might need to block until a
frame callback is received, but dispatching the default queue could cause an event
handler on the client to start drawing gain. This problem is solved using another
event queue, so that only the events handled by the EGL code are dispatched during
the block.
Parameters
name_or_fd (int or str) -- Either the name of the display to create or the
file descriptor to connect the display to. If not specified, then use the
default name, generally wayland-0
connect() -> None
Connect to a Wayland display
Connect to the Wayland display by name of fd. An int parameter opens the
connection using the file descriptor. The Display takes ownership of the fd
and will close it when the display is destroyed. The fd will also be closed
in case of failure. A string will open the display of the given name. If
name is None, its value will be replaced with the WAYLAND_DISPLAY
environment variable if it is set, otherwise display "wayland-0" will be
used.
disconnect() -> None
Close a connection to a Wayland display
Close the connection to display and free all resources associated with it.
dispatch(*, block: bool = False, queue: EventQueue | None = None) -> int
Process incoming events
If block is False, it does not attempt to read the display fd or event queue
and simply returns zero if the queue is empty.
If the given queue is empty and block is True, this function blocks until
there are events to be read from the display fd. Events are read and queued
on the appropriate event queues. Finally, events on the default event queue
are dispatched.
NOTE:
It is not possible to check if there are events on the queue or not.
flush() -> int
Send all buffered requests on the display to the server
Send all buffered data on the client side to the server. Clients should call
this function before blocking. On success, the number of bytes sent to the
server is returned. On failure, this function returns -1 and errno is set
appropriately.
Display.flush() never blocks. It will write as much data as possible, but
if all data could not be written, errno will be set to EAGAIN and -1
returned. In that case, use poll on the display file descriptor to wait for
it to become writable again.
get_fd() -> int
Get a display context's file descriptor
Return the file descriptor associated with a display so it can be integrated
into the client's main loop.
read(*, queue: EventQueue | None = None) -> None
Read events from display file descriptor
Calling this function will result in data available on the display file
descriptor being read and read events will be queued on their corresponding
event queues.
Parameters
queue -- If specified, queue the events onto the given event queue,
otherwise the default display queue will be used.
roundtrip(*, queue: EventQueue | None = None) -> int
Block until all pending request are processed by the server
This function blocks until the server has processed all currently issued
requests by sending a request to the display server and waiting for a reply
before returning.
This function uses wl_display_dispatch_queue() internally. It is not allowed
to call this function while the thread is being prepared for reading events,
and doing so will cause a dead lock.
NOTE:
This function may dispatch other events being received on the default
queue.
Parameters
queue (EventQueue) -- The queue on which to run the roundtrip, if not
given, uses the default queue.
Returns
The number of dispatched events on success or -1 on failure
EventQueue
class pywayland.client.EventQueue(display: Display)
A queue for wl_proxy object events.
Event queues allows the events on a display to be handled in a thread-safe manner.
See Display for details.
Parameters
display (Display) -- The display object that the event queue is connected
to.
destroy() -> None
Destroy an event queue
Destroy the given event queue. Any pending event on that queue is discarded.
The wl_display object used to create the queue should not be destroyed until
all event queues created with it are destroyed with this function.
property destroyed: bool
Determine the state of the event queue
Server Modules
The base set of objects used by Wayland servers.
Client
class pywayland.server.Client(display: ~pywayland.server.display.Display | None = None,
fd: int | None = None, ptr: <MagicMock name='mock.ffi.ClientCData.__or__()'
id='140737181137280'> = None)
Create a client for the given file descriptor
Given a file descriptor corresponding to one end of a socket, create a client
struct and add the new client to the compositors client list. At that point, the
client is initialized and ready to run, as if the client had connected to the
servers listening socket. Alternatively, pass a pointer to an existing client and
use that instead of creating a new one.
The other end of the socket can be passed to connect() on the client side or used
with the WAYLAND_SOCKET environment variable on the client side.
Parameters
• display (Display) -- The display object
• fd (int) -- The file descriptor for the socket to the client
• ptr (ffi.ClientCData) -- A pointer to an existing wl_client
add_destroy_listener(listener: Listener) -> None
Add a listener for the destroy signal
Parameters
listener (Listener) -- The listener object
destroy() -> None
Destroy the client
flush() -> None
Flush pending events to the client
Events sent to clients are queued in a buffer and written to the socket
later - typically when the compositor has handled all requests and goes back
to block in the event loop. This function flushes all queued up events for
a client immediately.
classmethod from_resource(resource: <MagicMock name='mock.ffi.ResourceCData'
id='140737181137280'>) -> Client
Look up the corresponding wl_client for a wl_resource
Parameters
resource (pywayland.protocol_core.Resource) -- The wl_resource
Returns
A Client instance.
get_credentials() -> tuple[int, int, int]
Return Unix credentials for the client.
This function returns the process ID, the user ID and the group ID for the
given client. The credentials come from getsockopt() with SO_PEERCRED, on
the client socket fd.
get_object(object_id: int) -> Any
Look up an object in the client name space
This looks up an object in the client object name space by its object ID.
Parameters
object_id (int) -- The object id
Returns
The object, or None if there is not object for the given ID
Display
class pywayland.server.Display(ptr=None)
Create a Wayland Display object
add_shm_format(shm_format) -> None
Add support for a Shm pixel format
Add the specified format format to the list of formats the WlShm object
advertises when a client binds to it. Adding a format to the list means
that clients will know that the compositor supports this format and may use
it for creating WlShm buffers. The compositor must be able to handle the
pixel format when a client requests it.
The compositor by default supports WL_SHM_FORMAT_ARGB8888 and
WL_SHM_FORMAT_XRGB8888.
Parameters
shm_format (format) -- The shm pixel format to advertise
add_socket(name: str | None = None) -> str
Add a socket to Wayland display for the clients to connect.
This adds a Unix socket to Wayland display which can be used by clients to
connect to Wayland display.
If None is passed as name, then it would look for WAYLAND_DISPLAY
environment variable for the socket name. If WAYLAND_DISPLAY is not set,
then default wayland-0 is used.
The Unix socket will be created in the directory pointed to by environment
variable XDG_RUNTIME_DIR. If XDG_RUNTIME_DIR is not set, then this function
throws an exception.
The length of socket path, i.e., the path set in XDG_RUNTIME_DIR and the
socket name, must not exceed the maxium length of a Unix socket path. The
function also fails if the user do not have write permission in the
XDG_RUNTIME_DIR path or if the socket name is already in use.
Parameters
name (string or None) -- Name of the Unix socket.
destroy() -> None
Destroy Wayland display object.
This function emits the Display destroy signal, releases all the sockets
added to this display, free's all the globals associated with this display,
free's memory of additional shared memory formats and destroy the display
object.
SEE ALSO:
Display.add_destroy_listener()
property destroyed: bool
Returns if the display has been destroyed
flush_clients() -> None
Flush client connections
get_event_loop() -> EventLoop
Get the event loop for the display
Returns
The EventLoop for the Display
get_serial() -> int
Get the current serial number
This function returns the most recent serial number, but does not increment
it.
init_shm() -> None
Initialize shm for this display
next_serial() -> int
Get the next serial
This function increments the display serial number and returns the new
value.
run() -> None
Run the display
terminate() -> None
Stop the display from running
EventLoop
class pywayland.server.EventLoop(display: Display | None = None)
An event loop to add events to
Returns an event loop. Either returns the event loop of a given display (which
will trigger when the Display is run), or creates a new event loop (which can be
triggered by using EventLoop.dispatch()).
Parameters
display (Display) -- The display to create the EventLoop on (default to
None)
class FdMask(value, names=<not given>, *values, module=None, qualname=None,
type=None, start=1, boundary=None)
add_destroy_listener(listener)
Add a listener for the destroy signal
Parameters
listener (Listener) -- The listener object
add_fd(fd, callback, mask=<FdMask.WL_EVENT_READABLE: 1>, data=None)
Add file descriptor callback
Triggers function call when file descriptor state matches the mask.
The callback should take three arguments:
• fd - file descriptor (int)
• mask - file descriptor mask (uint)
• data - any object
Parameters
• fd (int) -- File descriptor
• callback -- Callback function
• mask -- File descriptor mask
• data (object) -- User data to send to callback
Returns
EventSource for specified callback
SEE ALSO:
pywayland.server.eventloop.EventSource.check()
add_idle(callback, data=None)
Add idle callback
Parameters
• callback (function with callback void(void *data)) -- Callback
function
• data -- User data to send to callback
Returns
EventSource for specified callback
add_signal(signal_number, callback, data=None)
Add signal callback
Triggers function call signal is received.
The callback should take three arguments:
• signal_number - signal (int)
• data - any object
Parameters
• signal_number (int) -- Signal number to trigger on
• callback -- Callback function
• data (object) -- User data to send to callback
Returns
EventSource for specified callback
add_timer(callback, data=None)
Add timer callback
Triggers function call after a specified time.
The callback should take one argument:
• data - any object
Parameters
• callback (function with callback int(void *data)) -- Callback
function
• data (object) -- User data to send to callback
Returns
EventSource for specified callback
SEE ALSO:
pywayland.server.eventloop.EventSource.timer_update()
destroy()
Destroy the event loop
dispatch(timeout)
Dispatch callbacks on the event loop
dispatch_idle()
Dispatch idle callback on the event loop
Listener
class pywayland.server.Listener(function: Callable)
A single listener for Wayland signals
Provides the means to listen for wl_listener signal notifications. Many Wayland
objects use wl_listener for notification of significant events like object
destruction.
Clients should create Listener objects manually and can register them as listeners
to objects destroy events using the object's .add_destroy_listener() method. A
listener can only listen to one signal at a time.
Parameters
function (callable) -- callback function for the Listener
remove() -> None
Remove the listener
Protocol Core Modules
Interface
Interface objects are only created as a subclass of Interface. The Interface class wraps
the protocol objects, and serves to initialize a set of parameters for the Interface and
provide decorators for defining Message objects on the interface.
class pywayland.protocol_core.Interface
Wrapper class for wl_wayland structs
Base class for interfaces that are defined by the wayland.xml class and generated
by the scanner. Sub-classes should use the InterfaceMeta metaclass, which will
define subclass.events and subclass.requests, the lists of the methods on this
interface. These class variables are populated by the Interface.event() and
Interface.request() decorators.
classmethod event(*arguments: Argument, version: int | None = None) -> Callable
Decorator for interface events
Adds the decorated method to the list of events of the interface
(server-side method).
Parameters
• signature (string) -- Encodes the types of the arguments to the
decorated function.
• types (list) -- List of the types of any objects included in the
argument list, None if otherwise.
classmethod request(*arguments: Argument, version: int | None = None)
Decorator for interface requests
Adds the decorated method to the list of requests of the interface
(client-side method).
Parameters
• signature (string) -- Encodes the types of the arguments to the
decorated function.
• types (list) -- List of the types of any objects included in the
argument list, None if otherwise.
Interface Metaclass
This metaclass initializes lists for the requests and events on an interface and
initializes a cdata struct for the class.
class pywayland.protocol_core.interface.InterfaceMeta(name, bases, dct)
Metaclass for Interfaces
Initializes empty lists for events and requests for the given class.
Proxy
Proxy objects are not created directly, and users should generally not create a proxy
class on their own. Proxy classes give client side access to the interfaces defined by
the Wayland protocol. Proxies are returned from the server after calling protocol methods
which return new_id's.
class pywayland.protocol_core.Proxy(ptr, display=None)
destroy() -> None
Frees the pointer associated with the Proxy
property destroyed: bool
Determine if proxy has been destroyed
Returns true if the proxy has been destroyed.
Resource
class pywayland.protocol_core.Resource(client, version: int | None = None, id: int = 0)
A server-side Interface object for the client
Not created directly, created from the Interface object.
Parameters
• client (Client or cdata for wl_client *) -- The client that the Resource
is for
• version (int) -- The version to use for the Interface, uses current
version if not specified
• id (int) -- The id for the item
add_destroy_listener(listener) -> None
Add a listener for the destroy signal
Parameters
listener (Listener) -- The listener object
destroy() -> None
Destroy the Resource
Global
class pywayland.protocol_core.Global(display, version=None)
A server-side Interface object for the server
Not created directly, created from the Interface object.
Parameters
• display (Display) -- The display the object is created on
• version (int) -- The version to use for the Interface, uses current
version if not specified
destroy()
Destroy the global object
Message
Message objects are used to wrap the method calls on the protocol objects. The Message
objects are added to the Interface's as either requests (client-side functions) or events
(server-side functions).
class pywayland.protocol_core.message.Message(func: Callable, arguments: list[Argument],
version: int | None)
Wrapper class for wl_message structs
Base class that correspond to the methods defined on an interface in the
wayland.xml protocol, and are generated by the scanner. Subclasses specify the
type of method, whether it is a server-side or client-side method.
Parameters
• func (function) -- The function that is represented by the message
• signature (string) -- The signature of the arguments of the message
• types (list) -- List of the types of any objects included in the argument
list, None if otherwise.
arguments_to_c(*args)
Create an array of wl_argument C structs
Generate the CFFI cdata array of wl_argument structs that correspond to the
arguments of the method as specified by the method signature.
Parameters
args (list) -- Input arguments
Returns
cdata union wl_argument [] of args
build_message_struct(wl_message_struct) -> tuple
Bulid the wl_message struct for this message
Parameters
wl_message_struct -- The wl_message cdata struct to use to build the
message struct.
Returns
A tuple of elements which must be kept alive for the message struct
to remain valid.
c_to_arguments(args_ptr)
Create a list of arguments
Generate the arguments of the method from a CFFI cdata array of wl_argument
structs that correspond to the arguments of the method as specified by the
method signature.
Parameters
args_ptr (cdata union wl_argument []) -- Input arguments
Returns
list of args
Argument
class pywayland.protocol_core.argument.Argument(argument_type: 'ArgumentType', nullable:
'bool' = False, interface: 'type[Interface] | None' = None)
ArgumentType
class pywayland.protocol_core.argument.ArgumentType(value, names=<not given>, *values,
module=None, qualname=None, type=None, start=1, boundary=None)
Protocol Modules
Wayland protocols built against Wayland 1.21.0 and Wayland Protocols 1.25.
wayland Module
WlBuffer
class pywayland.protocol.wayland.WlBuffer
Content for a WlSurface
A buffer provides the content for a WlSurface. Buffers are created through factory
interfaces such as WlShm, wp_linux_buffer_params (from the linux-dmabuf protocol
extension) or similar. It has a width and a height and can be attached to a
WlSurface, but the mechanism by which a client provides and updates the contents is
defined by the buffer factory interface.
Color channels are assumed to be electrical rather than optical (in other words,
encoded with a transfer function) unless otherwise specified. If the buffer uses a
format that has an alpha channel, the alpha channel is assumed to be premultiplied
into the electrical color channel values (after transfer function encoding) unless
otherwise specified.
Note, because WlBuffer objects are created from multiple independent factory
interfaces, the WlBuffer interface is frozen at version 1.
destroy() -> 'None'
Request -- opcode 0 (attached to Resource instance)
Destroy a buffer
Destroy a buffer. If and how you need to release the backing storage is
defined by the buffer factory interface.
For possible side-effects to a surface, see WlSurface.attach().
release() -> 'None'
Event -- opcode 0 (attached to Proxy instance)
Compositor releases buffer
Sent when this WlBuffer is no longer used by the compositor. The client is
now free to reuse or destroy this buffer and its backing storage.
If a client receives a release event before the frame callback requested in
the same WlSurface.commit() that attaches this WlBuffer to a surface, then
the client is immediately free to reuse the buffer and its backing storage,
and does not need a second buffer for the next surface content update.
Typically this is possible, when the compositor maintains a copy of the
WlSurface contents, e.g. as a GL texture. This is an important optimization
for GL(ES) compositors with WlShm clients.
WlCallback
class pywayland.protocol.wayland.WlCallback
Callback object
Clients can handle the 'done' event to get notified when the related request is
done.
Note, because WlCallback objects are created from multiple independent factory
interfaces, the WlCallback interface is frozen at version 1.
done(callback_data: 'int') -> 'None'
Event -- opcode 0 (attached to Proxy instance)
Done event
Notify the client when the related request is done.
Parameters
callback_data (ArgumentType.Uint) -- request-specific data for the
callback
WlCompositor
class pywayland.protocol.wayland.WlCompositor
The compositor singleton
A compositor. This object is a singleton global. The compositor is in charge of
combining the contents of multiple surfaces into one displayable output.
create_surface() -> 'Proxy[WlSurface]'
Request -- opcode 0 (attached to Resource instance)
Create new surface
Ask the compositor to create a new surface.
Returns
WlSurface -- the new surface
create_region() -> 'Proxy[WlRegion]'
Request -- opcode 1 (attached to Resource instance)
Create new region
Ask the compositor to create a new region.
Returns
WlRegion -- the new region
WlDataDevice
class pywayland.protocol.wayland.WlDataDevice
Data transfer device
There is one WlDataDevice per seat which can be obtained from the global
WlDataDeviceManager singleton.
A WlDataDevice provides access to inter-client data transfer mechanisms such as
copy-and-paste and drag-and-drop.
start_drag(source: 'WlDataSource | None', origin: 'WlSurface', icon: 'WlSurface |
None', serial: 'int') -> 'None'
Request -- opcode 0 (attached to Resource instance)
Start drag-and-drop operation
This request asks the compositor to start a drag-and-drop operation on
behalf of the client.
The source argument is the data source that provides the data for the
eventual data transfer. If source is NULL, enter, leave and motion events
are sent only to the client that initiated the drag and the client is
expected to handle the data passing internally. If source is destroyed, the
drag-and-drop session will be cancelled.
The origin surface is the surface where the drag originates and the client
must have an active implicit grab that matches the serial.
The icon surface is an optional (can be NULL) surface that provides an icon
to be moved around with the cursor. Initially, the top-left corner of the
icon surface is placed at the cursor hotspot, but subsequent
WlSurface.offset() requests can move the relative position. Attach requests
must be confirmed with WlSurface.commit() as usual. The icon surface is
given the role of a drag-and-drop icon. If the icon surface already has
another role, it raises a protocol error.
The input region is ignored for wl_surfaces with the role of a drag-
and-drop icon.
The given source may not be used in any further set_selection or start_drag
requests. Attempting to reuse a previously-used source may send a
used_source error.
Parameters
• source (WlDataSource or None) -- data source for the eventual
transfer
• origin (WlSurface) -- surface where the drag originates
• icon (WlSurface or None) -- drag-and-drop icon surface
• serial (ArgumentType.Uint) -- serial number of the implicit grab on
the origin
set_selection(source: 'WlDataSource | None', serial: 'int') -> 'None'
Request -- opcode 1 (attached to Resource instance)
Copy data to the selection
This request asks the compositor to set the selection to the data from the
source on behalf of the client.
To unset the selection, set the source to NULL.
The given source may not be used in any further set_selection or start_drag
requests. Attempting to reuse a previously-used source may send a
used_source error.
Parameters
• source (WlDataSource or None) -- data source for the selection
• serial (ArgumentType.Uint) -- serial number of the event that
triggered this request
release() -> 'None'
Request -- opcode 2 (attached to Resource instance)
Destroy data device
This request destroys the data device.
data_offer(id: 'WlDataOffer') -> 'None'
Event -- opcode 0 (attached to Proxy instance)
Introduce a new WlDataOffer
The data_offer event introduces a new WlDataOffer object, which will
subsequently be used in either the data_device.enter event (for drag-
and-drop) or the data_device.selection event (for selections). Immediately
following the data_device.data_offer event, the new data_offer object will
send out data_offer.offer events to describe the mime types it offers.
Parameters
id (WlDataOffer) -- the new data_offer object
enter(serial: 'int', surface: 'WlSurface', x: 'float', y: 'float', id: 'WlDataOffer
| None') -> 'None'
Event -- opcode 1 (attached to Proxy instance)
Initiate drag-and-drop session
This event is sent when an active drag-and-drop pointer enters a surface
owned by the client. The position of the pointer at enter time is provided
by the x and y arguments, in surface-local coordinates.
Parameters
• serial (ArgumentType.Uint) -- serial number of the enter event
• surface (WlSurface) -- client surface entered
• x (ArgumentType.Fixed) -- surface-local x coordinate
• y (ArgumentType.Fixed) -- surface-local y coordinate
• id (WlDataOffer or None) -- source data_offer object
leave() -> 'None'
Event -- opcode 2 (attached to Proxy instance)
End drag-and-drop session
This event is sent when the drag-and-drop pointer leaves the surface and the
session ends. The client must destroy the WlDataOffer introduced at enter
time at this point.
motion(time: 'int', x: 'float', y: 'float') -> 'None'
Event -- opcode 3 (attached to Proxy instance)
Drag-and-drop session motion
This event is sent when the drag-and-drop pointer moves within the currently
focused surface. The new position of the pointer is provided by the x and y
arguments, in surface-local coordinates.
Parameters
• time (ArgumentType.Uint) -- timestamp with millisecond granularity
• x (ArgumentType.Fixed) -- surface-local x coordinate
• y (ArgumentType.Fixed) -- surface-local y coordinate
drop() -> 'None'
Event -- opcode 4 (attached to Proxy instance)
End drag-and-drop session successfully
The event is sent when a drag-and-drop operation is ended because the
implicit grab is removed.
The drag-and-drop destination is expected to honor the last action received
through WlDataOffer.action(), if the resulting action is "copy" or "move",
the destination can still perform WlDataOffer.receive() requests, and is
expected to end all transfers with a WlDataOffer.finish() request.
If the resulting action is "ask", the action will not be considered final.
The drag-and-drop destination is expected to perform one last
WlDataOffer.set_actions() request, or WlDataOffer.destroy() in order to
cancel the operation.
selection(id: 'WlDataOffer | None') -> 'None'
Event -- opcode 5 (attached to Proxy instance)
Advertise new selection
The selection event is sent out to notify the client of a new WlDataOffer
for the selection for this device. The data_device.data_offer and the
data_offer.offer events are sent out immediately before this event to
introduce the data offer object. The selection event is sent to a client
immediately before receiving keyboard focus and when a new selection is set
while the client has keyboard focus. The data_offer is valid until a new
data_offer or NULL is received or until the client loses keyboard focus.
Switching surface with keyboard focus within the same client doesn't mean a
new selection will be sent. The client must destroy the previous selection
data_offer, if any, upon receiving this event.
Parameters
id (WlDataOffer or None) -- selection data_offer object
WlDataDeviceManager
class pywayland.protocol.wayland.WlDataDeviceManager
Data transfer interface
The WlDataDeviceManager is a singleton global object that provides access to
inter-client data transfer mechanisms such as copy-and-paste and drag-and-drop.
These mechanisms are tied to a WlSeat and this interface lets a client get a
WlDataDevice corresponding to a WlSeat.
Depending on the version bound, the objects created from the bound
WlDataDeviceManager object will have different requirements for functioning
properly. See WlDataSource.set_actions(), WlDataOffer.accept() and
WlDataOffer.finish() for details.
create_data_source() -> 'Proxy[WlDataSource]'
Request -- opcode 0 (attached to Resource instance)
Create a new data source
Create a new data source.
Returns
WlDataSource -- data source to create
get_data_device(seat: 'WlSeat') -> 'Proxy[WlDataDevice]'
Request -- opcode 1 (attached to Resource instance)
Create a new data device
Create a new data device for a given seat.
Parameters
seat (WlSeat) -- seat associated with the data device
Returns
WlDataDevice -- data device to create
WlDataOffer
class pywayland.protocol.wayland.WlDataOffer
Offer to transfer data
A WlDataOffer represents a piece of data offered for transfer by another client
(the source client). It is used by the copy-and-paste and drag-and-drop
mechanisms. The offer describes the different mime types that the data can be
converted to and provides the mechanism for transferring the data directly from the
source client.
accept(serial: 'int', mime_type: 'str | None') -> 'None'
Request -- opcode 0 (attached to Resource instance)
Accept one of the offered mime types
Indicate that the client can accept the given mime type, or NULL for not
accepted.
For objects of version 2 or older, this request is used by the client to
give feedback whether the client can receive the given mime type, or NULL if
none is accepted; the feedback does not determine whether the drag-and-drop
operation succeeds or not.
For objects of version 3 or newer, this request determines the final result
of the drag-and-drop operation. If the end result is that no mime types were
accepted, the drag-and-drop operation will be cancelled and the
corresponding drag source will receive WlDataSource.cancelled(). Clients may
still use this event in conjunction with WlDataSource.action() for feedback.
Parameters
• serial (ArgumentType.Uint) -- serial number of the accept request
• mime_type (ArgumentType.String or None) -- mime type accepted by
the client
receive(mime_type: 'str', fd: 'int') -> 'None'
Request -- opcode 1 (attached to Resource instance)
Request that the data is transferred
To transfer the offered data, the client issues this request and indicates
the mime type it wants to receive. The transfer happens through the passed
file descriptor (typically created with the pipe system call). The source
client writes the data in the mime type representation requested and then
closes the file descriptor.
The receiving client reads from the read end of the pipe until EOF and then
closes its end, at which point the transfer is complete.
This request may happen multiple times for different mime types, both before
and after WlDataDevice.drop(). Drag-and-drop destination clients may
preemptively fetch data or examine it more closely to determine acceptance.
Parameters
• mime_type (ArgumentType.String) -- mime type desired by receiver
• fd (ArgumentType.FileDescriptor) -- file descriptor for data
transfer
destroy() -> 'None'
Request -- opcode 2 (attached to Resource instance)
Destroy data offer
Destroy the data offer.
finish() -> 'None'
Request -- opcode 3 (attached to Resource instance)
The offer will no longer be used
Notifies the compositor that the drag destination successfully finished the
drag-and-drop operation.
Upon receiving this request, the compositor will emit
WlDataSource.dnd_finished() on the drag source client.
It is a client error to perform other requests than WlDataOffer.destroy()
after this one. It is also an error to perform this request after a NULL
mime type has been set in WlDataOffer.accept() or no action was received
through WlDataOffer.action().
If WlDataOffer.finish() request is received for a non drag and drop
operation, the invalid_finish protocol error is raised.
set_actions(dnd_actions: 'int', preferred_action: 'int') -> 'None'
Request -- opcode 4 (attached to Resource instance)
Set the available/preferred drag-and-drop actions
Sets the actions that the destination side client supports for this
operation. This request may trigger the emission of WlDataSource.action()
and WlDataOffer.action() events if the compositor needs to change the
selected action.
This request can be called multiple times throughout the drag-and-drop
operation, typically in response to WlDataDevice.enter() or
WlDataDevice.motion() events.
This request determines the final result of the drag-and-drop operation. If
the end result is that no action is accepted, the drag source will receive
WlDataSource.cancelled().
The dnd_actions argument must contain only values expressed in the
WlDataDeviceManager.dnd_actions() enum, and the preferred_action argument
must only contain one of those values set, otherwise it will result in a
protocol error.
While managing an "ask" action, the destination drag-and-drop client may
perform further WlDataOffer.receive() requests, and is expected to perform
one last WlDataOffer.set_actions() request with a preferred action other
than "ask" (and optionally WlDataOffer.accept()) before requesting
WlDataOffer.finish(), in order to convey the action selected by the user. If
the preferred action is not in the WlDataOffer.source_actions() mask, an
error will be raised.
If the "ask" action is dismissed (e.g. user cancellation), the client is
expected to perform WlDataOffer.destroy() right away.
This request can only be made on drag-and-drop offers, a protocol error will
be raised otherwise.
Parameters
• dnd_actions (ArgumentType.Uint) -- actions supported by the
destination client
• preferred_action (ArgumentType.Uint) -- action preferred by the
destination client
offer(mime_type: 'str') -> 'None'
Event -- opcode 0 (attached to Proxy instance)
Advertise offered mime type
Sent immediately after creating the WlDataOffer object. One event per
offered mime type.
Parameters
mime_type (ArgumentType.String) -- offered mime type
source_actions(source_actions: 'int') -> 'None'
Event -- opcode 1 (attached to Proxy instance)
Notify the source-side available actions
This event indicates the actions offered by the data source. It will be sent
immediately after creating the WlDataOffer object, or anytime the source
side changes its offered actions through WlDataSource.set_actions().
Parameters
source_actions (ArgumentType.Uint) -- actions offered by the data
source
action(dnd_action: 'int') -> 'None'
Event -- opcode 2 (attached to Proxy instance)
Notify the selected action
This event indicates the action selected by the compositor after matching
the source/destination side actions. Only one action (or none) will be
offered here.
This event can be emitted multiple times during the drag-and-drop operation
in response to destination side action changes through
WlDataOffer.set_actions().
This event will no longer be emitted after WlDataDevice.drop() happened on
the drag- and-drop destination, the client must honor the last action
received, or the last preferred one set through WlDataOffer.set_actions()
when handling an "ask" action.
Compositors may also change the selected action on the fly, mainly in
response to keyboard modifier changes during the drag-and-drop operation.
The most recent action received is always the valid one. Prior to receiving
WlDataDevice.drop(), the chosen action may change (e.g. due to keyboard
modifiers being pressed). At the time of receiving WlDataDevice.drop() the
drag-and-drop destination must honor the last action received.
Action changes may still happen after WlDataDevice.drop(), especially on
"ask" actions, where the drag-and-drop destination may choose another action
afterwards. Action changes happening at this stage are always the result of
inter-client negotiation, the compositor shall no longer be able to induce a
different action.
Upon "ask" actions, it is expected that the drag-and-drop destination may
potentially choose a different action and/or mime type, based on
WlDataOffer.source_actions() and finally chosen by the user (e.g. popping up
a menu with the available options). The final WlDataOffer.set_actions() and
WlDataOffer.accept() requests must happen before the call to
WlDataOffer.finish().
Parameters
dnd_action (ArgumentType.Uint) -- action selected by the compositor
WlDataSource
class pywayland.protocol.wayland.WlDataSource
Offer to transfer data
The WlDataSource object is the source side of a WlDataOffer. It is created by the
source client in a data transfer and provides a way to describe the offered data
and a way to respond to requests to transfer the data.
offer(mime_type: 'str') -> 'None'
Request -- opcode 0 (attached to Resource instance)
Add an offered mime type
This request adds a mime type to the set of mime types advertised to
targets. Can be called several times to offer multiple types.
Parameters
mime_type (ArgumentType.String) -- mime type offered by the data
source
destroy() -> 'None'
Request -- opcode 1 (attached to Resource instance)
Destroy the data source
Destroy the data source.
set_actions(dnd_actions: 'int') -> 'None'
Request -- opcode 2 (attached to Resource instance)
Set the available drag-and-drop actions
Sets the actions that the source side client supports for this operation.
This request may trigger WlDataSource.action() and WlDataOffer.action()
events if the compositor needs to change the selected action.
The dnd_actions argument must contain only values expressed in the
WlDataDeviceManager.dnd_actions() enum, otherwise it will result in a
protocol error.
This request must be made once only, and can only be made on sources used in
drag-and-drop, so it must be performed before WlDataDevice.start_drag().
Attempting to use the source other than for drag-and-drop will raise a
protocol error.
Parameters
dnd_actions (ArgumentType.Uint) -- actions supported by the data
source
target(mime_type: 'str | None') -> 'None'
Event -- opcode 0 (attached to Proxy instance)
A target accepts an offered mime type
Sent when a target accepts pointer_focus or motion events. If a target does
not accept any of the offered types, type is NULL.
Used for feedback during drag-and-drop.
Parameters
mime_type (ArgumentType.String or None) -- mime type accepted by the
target
send(mime_type: 'str', fd: 'int') -> 'None'
Event -- opcode 1 (attached to Proxy instance)
Send the data
Request for data from the client. Send the data as the specified mime type
over the passed file descriptor, then close it.
Parameters
• mime_type (ArgumentType.String) -- mime type for the data
• fd (ArgumentType.FileDescriptor) -- file descriptor for the data
cancelled() -> 'None'
Event -- opcode 2 (attached to Proxy instance)
Selection was cancelled
This data source is no longer valid. There are several reasons why this
could happen:
• The data source has been replaced by another data source.
• The drag-and-drop operation was performed, but the drop destination did
not accept any of the mime types offered through WlDataSource.target().
• The drag-and-drop operation was performed, but the drop destination did
not select any of the actions present in the mask offered through
WlDataSource.action().
• The drag-and-drop operation was performed but didn't happen over a
surface.
• The compositor cancelled the drag-and-drop operation (e.g. compositor
dependent timeouts to avoid stale drag-and-drop transfers).
The client should clean up and destroy this data source.
For objects of version 2 or older, WlDataSource.cancelled() will only be
emitted if the data source was replaced by another data source.
dnd_drop_performed() -> 'None'
Event -- opcode 3 (attached to Proxy instance)
The drag-and-drop operation physically finished
The user performed the drop action. This event does not indicate acceptance,
WlDataSource.cancelled() may still be emitted afterwards if the drop
destination does not accept any mime type.
However, this event might however not be received if the compositor
cancelled the drag-and-drop operation before this event could happen.
Note that the data_source may still be used in the future and should not be
destroyed here.
dnd_finished() -> 'None'
Event -- opcode 4 (attached to Proxy instance)
The drag-and-drop operation concluded
The drop destination finished interoperating with this data source, so the
client is now free to destroy this data source and free all associated data.
If the action used to perform the operation was "move", the source can now
delete the transferred data.
action(dnd_action: 'int') -> 'None'
Event -- opcode 5 (attached to Proxy instance)
Notify the selected action
This event indicates the action selected by the compositor after matching
the source/destination side actions. Only one action (or none) will be
offered here.
This event can be emitted multiple times during the drag-and-drop operation,
mainly in response to destination side changes through
WlDataOffer.set_actions(), and as the data device enters/leaves surfaces.
It is only possible to receive this event after
WlDataSource.dnd_drop_performed() if the drag-and-drop operation ended in an
"ask" action, in which case the final WlDataSource.action() event will
happen immediately before WlDataSource.dnd_finished().
Compositors may also change the selected action on the fly, mainly in
response to keyboard modifier changes during the drag-and-drop operation.
The most recent action received is always the valid one. The chosen action
may change alongside negotiation (e.g. an "ask" action can turn into a
"move" operation), so the effects of the final action must always be applied
in WlDataOffer.dnd_finished().
Clients can trigger cursor surface changes from this point, so they reflect
the current action.
Parameters
dnd_action (ArgumentType.Uint) -- action selected by the compositor
WlDisplay
class pywayland.protocol.wayland.WlDisplay
Core global object
The core global object. This is a special singleton object. It is used for
internal Wayland protocol features.
sync() -> 'Proxy[WlCallback]'
Request -- opcode 0 (attached to Resource instance)
Asynchronous roundtrip
The sync request asks the server to emit the 'done' event on the returned
WlCallback object. Since requests are handled in-order and events are
delivered in-order, this can be used as a barrier to ensure all previous
requests and the resulting events have been handled.
The object returned by this request will be destroyed by the compositor
after the callback is fired and as such the client must not attempt to use
it after that point.
The callback_data passed in the callback is undefined and should be ignored.
Returns
WlCallback -- callback object for the sync request
get_registry() -> 'Proxy[WlRegistry]'
Request -- opcode 1 (attached to Resource instance)
Get global registry object
This request creates a registry object that allows the client to list and
bind the global objects available from the compositor.
It should be noted that the server side resources consumed in response to a
get_registry request can only be released when the client disconnects, not
when the client side proxy is destroyed. Therefore, clients should invoke
get_registry as infrequently as possible to avoid wasting memory.
Returns
WlRegistry -- global registry object
error(object_id: 'Any', code: 'int', message: 'str') -> 'None'
Event -- opcode 0 (attached to Proxy instance)
Fatal error event
The error event is sent out when a fatal (non-recoverable) error has
occurred. The object_id argument is the object where the error occurred,
most often in response to a request to that object. The code identifies the
error and is defined by the object interface. As such, each interface
defines its own set of error codes. The message is a brief description of
the error, for (debugging) convenience.
Parameters
• object_id (ArgumentType.Object) -- object where the error occurred
• code (ArgumentType.Uint) -- error code
• message (ArgumentType.String) -- error description
delete_id(id: 'int') -> 'None'
Event -- opcode 1 (attached to Proxy instance)
Acknowledge object id deletion
This event is used internally by the object ID management logic. When a
client deletes an object that it had created, the server will send this
event to acknowledge that it has seen the delete request. When the client
receives this event, it will know that it can safely reuse the object ID.
Parameters
id (ArgumentType.Uint) -- deleted object ID
WlKeyboard
class pywayland.protocol.wayland.WlKeyboard
Keyboard input device
The WlKeyboard interface represents one or more keyboards associated with a seat.
Each WlKeyboard has the following logical state:
• an active surface (possibly null),
• the keys currently logically down,
• the active modifiers,
• the active group.
By default, the active surface is null, the keys currently logically down are
empty, the active modifiers and the active group are 0.
release() -> 'None'
Request -- opcode 0 (attached to Resource instance)
Release the keyboard object
keymap(format: 'int', fd: 'int', size: 'int') -> 'None'
Event -- opcode 0 (attached to Proxy instance)
Keyboard mapping
This event provides a file descriptor to the client which can be
memory-mapped in read-only mode to provide a keyboard mapping description.
From version 7 onwards, the fd must be mapped with MAP_PRIVATE by the
recipient, as MAP_SHARED may fail.
Parameters
• format (ArgumentType.Uint) -- keymap format
• fd (ArgumentType.FileDescriptor) -- keymap file descriptor
• size (ArgumentType.Uint) -- keymap size, in bytes
enter(serial: 'int', surface: 'WlSurface', keys: 'list') -> 'None'
Event -- opcode 1 (attached to Proxy instance)
Enter event
Notification that this seat's keyboard focus is on a certain surface.
The compositor must send the WlKeyboard.modifiers() event after this event.
In the WlKeyboard logical state, this event sets the active surface to the
surface argument and the keys currently logically down to the keys in the
keys argument. The compositor must not send this event if the WlKeyboard
already had an active surface immediately before this event.
Parameters
• serial (ArgumentType.Uint) -- serial number of the enter event
• surface (WlSurface) -- surface gaining keyboard focus
• keys (ArgumentType.Array) -- the keys currently logically down
leave(serial: 'int', surface: 'WlSurface') -> 'None'
Event -- opcode 2 (attached to Proxy instance)
Leave event
Notification that this seat's keyboard focus is no longer on a certain
surface.
The leave notification is sent before the enter notification for the new
focus.
In the WlKeyboard logical state, this event resets all values to their
defaults. The compositor must not send this event if the active surface of
the WlKeyboard was not equal to the surface argument immediately before this
event.
Parameters
• serial (ArgumentType.Uint) -- serial number of the leave event
• surface (WlSurface) -- surface that lost keyboard focus
key(serial: 'int', time: 'int', key: 'int', state: 'int') -> 'None'
Event -- opcode 3 (attached to Proxy instance)
Key event
A key was pressed or released. The time argument is a timestamp with
millisecond granularity, with an undefined base.
The key is a platform-specific key code that can be interpreted by feeding
it to the keyboard mapping (see the keymap event).
If this event produces a change in modifiers, then the resulting
WlKeyboard.modifiers() event must be sent after this event.
In the WlKeyboard logical state, this event adds the key to the keys
currently logically down (if the state argument is pressed) or removes the
key from the keys currently logically down (if the state argument is
released). The compositor must not send this event if the WlKeyboard did not
have an active surface immediately before this event. The compositor must
not send this event if state is pressed (resp. released) and the key was
already logically down (resp. was not logically down) immediately before
this event.
Parameters
• serial (ArgumentType.Uint) -- serial number of the key event
• time (ArgumentType.Uint) -- timestamp with millisecond granularity
• key (ArgumentType.Uint) -- key that produced the event
• state (ArgumentType.Uint) -- physical state of the key
modifiers(serial: 'int', mods_depressed: 'int', mods_latched: 'int', mods_locked:
'int', group: 'int') -> 'None'
Event -- opcode 4 (attached to Proxy instance)
Modifier and group state
Notifies clients that the modifier and/or group state has changed, and it
should update its local state.
The compositor may send this event without a surface of the client having
keyboard focus, for example to tie modifier information to pointer focus
instead. If a modifier event with pressed modifiers is sent without a prior
enter event, the client can assume the modifier state is valid until it
receives the next WlKeyboard.modifiers() event. In order to reset the
modifier state again, the compositor can send a WlKeyboard.modifiers() event
with no pressed modifiers.
In the WlKeyboard logical state, this event updates the modifiers and group.
Parameters
• serial (ArgumentType.Uint) -- serial number of the modifiers event
• mods_depressed (ArgumentType.Uint) -- depressed modifiers
• mods_latched (ArgumentType.Uint) -- latched modifiers
• mods_locked (ArgumentType.Uint) -- locked modifiers
• group (ArgumentType.Uint) -- keyboard layout
repeat_info(rate: 'int', delay: 'int') -> 'None'
Event -- opcode 5 (attached to Proxy instance)
Repeat rate and delay
Informs the client about the keyboard's repeat rate and delay.
This event is sent as soon as the WlKeyboard object has been created, and is
guaranteed to be received by the client before any key press event.
Negative values for either rate or delay are illegal. A rate of zero will
disable any repeating (regardless of the value of delay).
This event can be sent later on as well with a new value if necessary, so
clients should continue listening for the event past the creation of
WlKeyboard.
Parameters
• rate (ArgumentType.Int) -- the rate of repeating keys in characters
per second
• delay (ArgumentType.Int) -- delay in milliseconds since key down
until repeating starts
WlOutput
class pywayland.protocol.wayland.WlOutput
Compositor output region
An output describes part of the compositor geometry. The compositor works in the
'compositor coordinate system' and an output corresponds to a rectangular area in
that space that is actually visible. This typically corresponds to a monitor that
displays part of the compositor space. This object is published as global during
start up, or when a monitor is hotplugged.
release() -> 'None'
Request -- opcode 0 (attached to Resource instance)
Release the output object
Using this request a client can tell the server that it is not going to use
the output object anymore.
geometry(x: 'int', y: 'int', physical_width: 'int', physical_height: 'int',
subpixel: 'int', make: 'str', model: 'str', transform: 'int') -> 'None'
Event -- opcode 0 (attached to Proxy instance)
Properties of the output
The geometry event describes geometric properties of the output. The event
is sent when binding to the output object and whenever any of the properties
change.
The physical size can be set to zero if it doesn't make sense for this
output (e.g. for projectors or virtual outputs).
The geometry event will be followed by a done event (starting from version
2).
Clients should use WlSurface.preferred_buffer_transform() instead of the
transform advertised by this event to find the preferred buffer transform to
use for a surface.
Note: WlOutput only advertises partial information about the output position
and identification. Some compositors, for instance those not implementing a
desktop-style output layout or those exposing virtual outputs, might fake
this information. Instead of using x and y, clients should use
xdg_output.logical_position. Instead of using make and model, clients should
use name and description.
Parameters
• x (ArgumentType.Int) -- x position within the global compositor
space
• y (ArgumentType.Int) -- y position within the global compositor
space
• physical_width (ArgumentType.Int) -- width in millimeters of the
output
• physical_height (ArgumentType.Int) -- height in millimeters of the
output
• subpixel (ArgumentType.Int) -- subpixel orientation of the output
• make (ArgumentType.String) -- textual description of the
manufacturer
• model (ArgumentType.String) -- textual description of the model
• transform (ArgumentType.Int) -- additional transformation applied
to buffer contents during presentation
mode(flags: 'int', width: 'int', height: 'int', refresh: 'int') -> 'None'
Event -- opcode 1 (attached to Proxy instance)
Advertise available modes for the output
The mode event describes an available mode for the output.
The event is sent when binding to the output object and there will always be
one mode, the current mode. The event is sent again if an output changes
mode, for the mode that is now current. In other words, the current mode is
always the last mode that was received with the current flag set.
Non-current modes are deprecated. A compositor can decide to only advertise
the current mode and never send other modes. Clients should not rely on
non-current modes.
The size of a mode 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, as described in
WlOutput.scale(), or transformed, as described in WlOutput.transform().
Clients willing to retrieve the output size in the global compositor space
should use xdg_output.logical_size instead.
The vertical refresh rate can be set to zero if it doesn't make sense for
this output (e.g. for virtual outputs).
The mode event will be followed by a done event (starting from version 2).
Clients should not use the refresh rate to schedule frames. Instead, they
should use the WlSurface.frame() event or the presentation-time protocol.
Note: this information is not always meaningful for all outputs. Some
compositors, such as those exposing virtual outputs, might fake the refresh
rate or the size.
Parameters
• flags (ArgumentType.Uint) -- bitfield of mode flags
• width (ArgumentType.Int) -- width of the mode in hardware units
• height (ArgumentType.Int) -- height of the mode in hardware units
• refresh (ArgumentType.Int) -- vertical refresh rate in mHz
done() -> 'None'
Event -- opcode 2 (attached to Proxy instance)
Sent all information about output
This event is sent after all other properties have been sent after binding
to the output object and after any other property changes done after that.
This allows changes to the output properties to be seen as atomic, even if
they happen via multiple events.
scale(factor: 'int') -> 'None'
Event -- opcode 3 (attached to Proxy instance)
Output scaling properties
This event contains scaling geometry information that is not in the geometry
event. It may be sent after binding the output object or if the output scale
changes later. The compositor will emit a non-zero, positive value for
scale. If it is not sent, the client should assume a scale of 1.
A scale larger than 1 means that the compositor will automatically scale
surface buffers by this amount when rendering. This is used for very high
resolution displays where applications rendering at the native resolution
would be too small to be legible.
Clients should use WlSurface.preferred_buffer_scale() instead of this event
to find the preferred buffer scale to use for a surface.
The scale event will be followed by a done event.
Parameters
factor (ArgumentType.Int) -- scaling factor of output
name(name: 'str') -> 'None'
Event -- opcode 4 (attached to Proxy instance)
Name of this output
Many compositors will assign user-friendly names to their outputs, show them
to the user, allow the user to refer to an output, etc. The client may wish
to know this name as well to offer the user similar behaviors.
The name is a UTF-8 string with no convention defined for its contents.
Each name is unique among all WlOutput globals. The name is only guaranteed
to be unique for the compositor instance.
The same output name is used for all clients for a given WlOutput global.
Thus, the name can be shared across processes to refer to a specific
WlOutput global.
The name is not guaranteed to be persistent across sessions, thus cannot be
used to reliably identify an output in e.g. configuration files.
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.
The name event is sent after binding the output object. This event is only
sent once per output object, and the name does not change over the lifetime
of the WlOutput global.
Compositors may re-use the same output name if the WlOutput global is
destroyed and re-created later. Compositors should avoid re- using the same
name if possible.
The name event will be followed by a done event.
Parameters
name (ArgumentType.String) -- output name
description(description: 'str') -> 'None'
Event -- opcode 5 (attached to Proxy instance)
Human-readable description of this output
Many compositors can produce human-readable descriptions of their outputs.
The client may wish to know this description as well, e.g. for output
selection purposes.
The description is a UTF-8 string with no convention defined for its
contents. The description is not guaranteed to be unique among all WlOutput
globals. Examples might include 'Foocorp 11" Display' or 'Virtual X11 output
via :1'.
The description event is sent after binding the output object and whenever
the description changes. The description is optional, and may not be sent at
all.
The description event will be followed by a done event.
Parameters
description (ArgumentType.String) -- output description
WlPointer
class pywayland.protocol.wayland.WlPointer
Pointer input device
The WlPointer interface represents one or more input devices, such as mice, which
control the pointer location and pointer_focus of a seat.
The WlPointer interface generates motion, enter and leave events for the surfaces
that the pointer is located over, and button and axis events for button presses,
button releases and scrolling.
set_cursor(serial: 'int', surface: 'WlSurface | None', hotspot_x: 'int', hotspot_y:
'int') -> 'None'
Request -- opcode 0 (attached to Resource instance)
Set the pointer surface
Set the pointer surface, i.e., the surface that contains the pointer image
(cursor). This request gives the surface the role of a cursor. If the
surface already has another role, it raises a protocol error.
The cursor actually changes only if the pointer focus for this device is one
of the requesting client's surfaces or the surface parameter is the current
pointer surface. If there was a previous surface set with this request it is
replaced. If surface is NULL, the pointer image is hidden.
The parameters hotspot_x and hotspot_y define the position of the pointer
surface relative to the pointer location. Its top-left corner is always at
(x, y) - (hotspot_x, hotspot_y), where (x, y) are the coordinates of the
pointer location, in surface-local coordinates.
On WlSurface.offset() requests to the pointer surface, hotspot_x and
hotspot_y are decremented by the x and y parameters passed to the request.
The offset must be applied by WlSurface.commit() as usual.
The hotspot can also be updated by passing the currently set pointer surface
to this request with new values for hotspot_x and hotspot_y.
The input region is ignored for wl_surfaces with the role of a cursor. When
the use as a cursor ends, the WlSurface is unmapped.
The serial parameter must match the latest WlPointer.enter() serial number
sent to the client. Otherwise the request will be ignored.
Parameters
• serial (ArgumentType.Uint) -- serial number of the enter event
• surface (WlSurface or None) -- pointer surface
• hotspot_x (ArgumentType.Int) -- surface-local x coordinate
• hotspot_y (ArgumentType.Int) -- surface-local y coordinate
release() -> 'None'
Request -- opcode 1 (attached to Resource instance)
Release the pointer object
Using this request a client can tell the server that it is not going to use
the pointer object anymore.
This request destroys the pointer proxy object, so clients must not call
wl_pointer_destroy() after using this request.
enter(serial: 'int', surface: 'WlSurface', surface_x: 'float', surface_y: 'float')
-> 'None'
Event -- opcode 0 (attached to Proxy instance)
Enter event
Notification that this seat's pointer is focused on a certain surface.
When a seat's focus enters a surface, the pointer image is undefined and a
client should respond to this event by setting an appropriate pointer image
with the set_cursor request.
Parameters
• serial (ArgumentType.Uint) -- serial number of the enter event
• surface (WlSurface) -- surface entered by the pointer
• surface_x (ArgumentType.Fixed) -- surface-local x coordinate
• surface_y (ArgumentType.Fixed) -- surface-local y coordinate
leave(serial: 'int', surface: 'WlSurface') -> 'None'
Event -- opcode 1 (attached to Proxy instance)
Leave event
Notification that this seat's pointer is no longer focused on a certain
surface.
The leave notification is sent before the enter notification for the new
focus.
Parameters
• serial (ArgumentType.Uint) -- serial number of the leave event
• surface (WlSurface) -- surface left by the pointer
motion(time: 'int', surface_x: 'float', surface_y: 'float') -> 'None'
Event -- opcode 2 (attached to Proxy instance)
Pointer motion event
Notification of pointer location change. The arguments surface_x and
surface_y are the location relative to the focused surface.
Parameters
• time (ArgumentType.Uint) -- timestamp with millisecond granularity
• surface_x (ArgumentType.Fixed) -- surface-local x coordinate
• surface_y (ArgumentType.Fixed) -- surface-local y coordinate
button(serial: 'int', time: 'int', button: 'int', state: 'int') -> 'None'
Event -- opcode 3 (attached to Proxy instance)
Pointer button event
Mouse button click and release notifications.
The location of the click is given by the last motion or enter event. The
time argument is a timestamp with millisecond granularity, with an undefined
base.
The button is a button code as defined in the Linux kernel's
linux/input-event-codes.h header file, e.g. BTN_LEFT.
Any 16-bit button code value is reserved for future additions to the
kernel's event code list. All other button codes above 0xFFFF are currently
undefined but may be used in future versions of this protocol.
Parameters
• serial (ArgumentType.Uint) -- serial number of the button event
• time (ArgumentType.Uint) -- timestamp with millisecond granularity
• button (ArgumentType.Uint) -- button that produced the event
• state (ArgumentType.Uint) -- physical state of the button
axis(time: 'int', axis: 'int', value: 'float') -> 'None'
Event -- opcode 4 (attached to Proxy instance)
Axis event
Scroll and other axis notifications.
For scroll events (vertical and horizontal scroll axes), the value parameter
is the length of a vector along the specified axis in a coordinate space
identical to those of motion events, representing a relative movement along
the specified axis.
For devices that support movements non-parallel to axes multiple axis events
will be emitted.
When applicable, for example for touch pads, the server can choose to emit
scroll events where the motion vector is equivalent to a motion event
vector.
When applicable, a client can transform its content relative to the scroll
distance.
Parameters
• time (ArgumentType.Uint) -- timestamp with millisecond granularity
• axis (ArgumentType.Uint) -- axis type
• value (ArgumentType.Fixed) -- length of vector in surface-local
coordinate space
frame() -> 'None'
Event -- opcode 5 (attached to Proxy instance)
End of a pointer event sequence
Indicates the end of a set of events that logically belong together. A
client is expected to accumulate the data in all events within the frame
before proceeding.
All WlPointer events before a WlPointer.frame() event belong logically
together. For example, in a diagonal scroll motion the compositor will send
an optional WlPointer.axis_source() event, two WlPointer.axis() events
(horizontal and vertical) and finally a WlPointer.frame() event. The client
may use this information to calculate a diagonal vector for scrolling.
When multiple WlPointer.axis() events occur within the same frame, the
motion vector is the combined motion of all events. When a WlPointer.axis()
and a WlPointer.axis_stop() event occur within the same frame, this
indicates that axis movement in one axis has stopped but continues in the
other axis. When multiple WlPointer.axis_stop() events occur within the same
frame, this indicates that these axes stopped in the same instance.
A WlPointer.frame() event is sent for every logical event group, even if the
group only contains a single WlPointer event. Specifically, a client may get
a sequence: motion, frame, button, frame, axis, frame, axis_stop, frame.
The WlPointer.enter() and WlPointer.leave() events are logical events
generated by the compositor and not the hardware. These events are also
grouped by a WlPointer.frame(). When a pointer moves from one surface to
another, a compositor should group the WlPointer.leave() event within the
same WlPointer.frame(). However, a client must not rely on WlPointer.leave()
and WlPointer.enter() being in the same WlPointer.frame().
Compositor-specific policies may require the WlPointer.leave() and
WlPointer.enter() event being split across multiple WlPointer.frame()
groups.
axis_source(axis_source: 'int') -> 'None'
Event -- opcode 6 (attached to Proxy instance)
Axis source event
Source information for scroll and other axes.
This event does not occur on its own. It is sent before a WlPointer.frame()
event and carries the source information for all events within that frame.
The source specifies how this event was generated. If the source is
WlPointer.axis_source().finger, a WlPointer.axis_stop() event will be sent
when the user lifts the finger off the device.
If the source is WlPointer.axis_source().wheel,
WlPointer.axis_source().wheel_tilt or WlPointer.axis_source().continuous, a
WlPointer.axis_stop() event may or may not be sent. Whether a compositor
sends an axis_stop event for these sources is hardware- specific and
implementation-dependent; clients must not rely on receiving an axis_stop
event for these scroll sources and should treat scroll sequences from these
scroll sources as unterminated by default.
This event is optional. If the source is unknown for a particular axis event
sequence, no event is sent. Only one WlPointer.axis_source() event is
permitted per frame.
The order of WlPointer.axis_discrete() and WlPointer.axis_source() is not
guaranteed.
Parameters
axis_source (ArgumentType.Uint) -- source of the axis event
axis_stop(time: 'int', axis: 'int') -> 'None'
Event -- opcode 7 (attached to Proxy instance)
Axis stop event
Stop notification for scroll and other axes.
For some WlPointer.axis_source() types, a WlPointer.axis_stop() event is
sent to notify a client that the axis sequence has terminated. This enables
the client to implement kinetic scrolling. See the WlPointer.axis_source()
documentation for information on when this event may be generated.
Any WlPointer.axis() events with the same axis_source after this event
should be considered as the start of a new axis motion.
The timestamp is to be interpreted identical to the timestamp in the
WlPointer.axis() event. The timestamp value may be the same as a preceding
WlPointer.axis() event.
Parameters
• time (ArgumentType.Uint) -- timestamp with millisecond granularity
• axis (ArgumentType.Uint) -- the axis stopped with this event
axis_discrete(axis: 'int', discrete: 'int') -> 'None'
Event -- opcode 8 (attached to Proxy instance)
Axis click event
Discrete step information for scroll and other axes.
This event carries the axis value of the WlPointer.axis() event in discrete
steps (e.g. mouse wheel clicks).
This event is deprecated with WlPointer version 8 - this event is not sent
to clients supporting version 8 or later.
This event does not occur on its own, it is coupled with a WlPointer.axis()
event that represents this axis value on a continuous scale. The protocol
guarantees that each axis_discrete event is always followed by exactly one
axis event with the same axis number within the same WlPointer.frame(). Note
that the protocol allows for other events to occur between the axis_discrete
and its coupled axis event, including other axis_discrete or axis events. A
WlPointer.frame() must not contain more than one axis_discrete event per
axis type.
This event is optional; continuous scrolling devices like two-finger
scrolling on touchpads do not have discrete steps and do not generate this
event.
The discrete value carries the directional information. e.g. a value of -2
is two steps towards the negative direction of this axis.
The axis number is identical to the axis number in the associated axis
event.
The order of WlPointer.axis_discrete() and WlPointer.axis_source() is not
guaranteed.
Parameters
• axis (ArgumentType.Uint) -- axis type
• discrete (ArgumentType.Int) -- number of steps
axis_value120(axis: 'int', value120: 'int') -> 'None'
Event -- opcode 9 (attached to Proxy instance)
Axis high-resolution scroll event
Discrete high-resolution scroll information.
This event carries high-resolution wheel scroll information, with each
multiple of 120 representing one logical scroll step (a wheel detent). For
example, an axis_value120 of 30 is one quarter of a logical scroll step in
the positive direction, a value120 of -240 are two logical scroll steps in
the negative direction within the same hardware event. Clients that rely on
discrete scrolling should accumulate the value120 to multiples of 120 before
processing the event.
The value120 must not be zero.
This event replaces the WlPointer.axis_discrete() event in clients
supporting WlPointer version 8 or later.
Where a WlPointer.axis_source() event occurs in the same WlPointer.frame(),
the axis source applies to this event.
The order of WlPointer.axis_value120 and WlPointer.axis_source() is not
guaranteed.
Parameters
• axis (ArgumentType.Uint) -- axis type
• value120 (ArgumentType.Int) -- scroll distance as fraction of 120
axis_relative_direction(axis: 'int', direction: 'int') -> 'None'
Event -- opcode 10 (attached to Proxy instance)
Axis relative physical direction event
Relative directional information of the entity causing the axis motion.
For a WlPointer.axis() event, the WlPointer.axis_relative_direction() event
specifies the movement direction of the entity causing the WlPointer.axis()
event. For example: - if a user's fingers on a touchpad move down and this
causes a WlPointer.axis() vertical_scroll down event, the physical
direction is 'identical' - if a user's fingers on a touchpad move down and
this causes a WlPointer.axis() vertical_scroll up scroll up event
('natural scrolling'), the physical direction is 'inverted'.
A client may use this information to adjust scroll motion of components.
Specifically, enabling natural scrolling causes the content to change
direction compared to traditional scrolling. Some widgets like volume
control sliders should usually match the physical direction regardless of
whether natural scrolling is active. This event enables clients to match the
scroll direction of a widget to the physical direction.
This event does not occur on its own, it is coupled with a WlPointer.axis()
event that represents this axis value. The protocol guarantees that each
axis_relative_direction event is always followed by exactly one axis event
with the same axis number within the same WlPointer.frame(). Note that the
protocol allows for other events to occur between the
axis_relative_direction and its coupled axis event.
The axis number is identical to the axis number in the associated axis
event.
The order of WlPointer.axis_relative_direction(), WlPointer.axis_discrete()
and WlPointer.axis_source() is not guaranteed.
Parameters
• axis (ArgumentType.Uint) -- axis type
• direction (ArgumentType.Uint) -- physical direction relative to
axis motion
WlRegion
class pywayland.protocol.wayland.WlRegion
Region interface
A region object describes an area.
Region objects are used to describe the opaque and input regions of a surface.
destroy() -> 'None'
Request -- opcode 0 (attached to Resource instance)
Destroy region
Destroy the region. This will invalidate the object ID.
add(x: 'int', y: 'int', width: 'int', height: 'int') -> 'None'
Request -- opcode 1 (attached to Resource instance)
Add rectangle to region
Add the specified rectangle to the region.
Parameters
• x (ArgumentType.Int) -- region-local x coordinate
• y (ArgumentType.Int) -- region-local y coordinate
• width (ArgumentType.Int) -- rectangle width
• height (ArgumentType.Int) -- rectangle height
subtract(x: 'int', y: 'int', width: 'int', height: 'int') -> 'None'
Request -- opcode 2 (attached to Resource instance)
Subtract rectangle from region
Subtract the specified rectangle from the region.
Parameters
• x (ArgumentType.Int) -- region-local x coordinate
• y (ArgumentType.Int) -- region-local y coordinate
• width (ArgumentType.Int) -- rectangle width
• height (ArgumentType.Int) -- rectangle height
WlRegistry
class pywayland.protocol.wayland.WlRegistry
Global registry object
The singleton global registry object. The server has a number of global objects
that are available to all clients. These objects typically represent an actual
object in the server (for example, an input device) or they are singleton objects
that provide extension functionality.
When a client creates a registry object, the registry object will emit a global
event for each global currently in the registry. Globals come and go as a result
of device or monitor hotplugs, reconfiguration or other events, and the registry
will send out global and global_remove events to keep the client up to date with
the changes. To mark the end of the initial burst of events, the client can use
the WlDisplay.sync() request immediately after calling WlDisplay.get_registry().
A client can bind to a global object by using the bind request. This creates a
client-side handle that lets the object emit events to the client and lets the
client invoke requests on the object.
bind(name: 'int', interface: 'type[T]', version: 'int') -> 'Proxy[T]'
Request -- opcode 0 (attached to Resource instance)
Bind an object to the display
Binds a new, client-created object to the server using the specified name as
the identifier.
Parameters
• name (ArgumentType.Uint) -- unique numeric name of the object
• interface (string) -- Interface name
• version (int) -- Interface version
Returns
pywayland.client.proxy.Proxy of specified Interface -- bounded object
global_(name: 'int', interface: 'str', version: 'int') -> 'None'
Event -- opcode 0 (attached to Proxy instance)
Announce global object
Notify the client of global objects.
The event notifies the client that a global object with the given name is
now available, and it implements the given version of the given interface.
Parameters
• name (ArgumentType.Uint) -- numeric name of the global object
• interface (ArgumentType.String) -- interface implemented by the
object
• version (ArgumentType.Uint) -- interface version
global_remove(name: 'int') -> 'None'
Event -- opcode 1 (attached to Proxy instance)
Announce removal of global object
Notify the client of removed global objects.
This event notifies the client that the global identified by name is no
longer available. If the client bound to the global using the bind request,
the client should now destroy that object.
The object remains valid and requests to the object will be ignored until
the client destroys it, to avoid races between the global going away and a
client sending a request to it.
Parameters
name (ArgumentType.Uint) -- numeric name of the global object
WlSeat
class pywayland.protocol.wayland.WlSeat
Group of input devices
A seat is a group of keyboards, pointer and touch devices. This object is published
as a global during start up, or when such a device is hot plugged. A seat
typically has a pointer and maintains a keyboard focus and a pointer focus.
get_pointer() -> 'Proxy[WlPointer]'
Request -- opcode 0 (attached to Resource instance)
Return pointer object
The ID provided will be initialized to the WlPointer interface for this
seat.
This request only takes effect if the seat has the pointer capability, or
has had the pointer capability in the past. It is a protocol violation to
issue this request on a seat that has never had the pointer capability. The
missing_capability error will be sent in this case.
Returns
WlPointer -- seat pointer
get_keyboard() -> 'Proxy[WlKeyboard]'
Request -- opcode 1 (attached to Resource instance)
Return keyboard object
The ID provided will be initialized to the WlKeyboard interface for this
seat.
This request only takes effect if the seat has the keyboard capability, or
has had the keyboard capability in the past. It is a protocol violation to
issue this request on a seat that has never had the keyboard capability. The
missing_capability error will be sent in this case.
Returns
WlKeyboard -- seat keyboard
get_touch() -> 'Proxy[WlTouch]'
Request -- opcode 2 (attached to Resource instance)
Return touch object
The ID provided will be initialized to the WlTouch interface for this seat.
This request only takes effect if the seat has the touch capability, or has
had the touch capability in the past. It is a protocol violation to issue
this request on a seat that has never had the touch capability. The
missing_capability error will be sent in this case.
Returns
WlTouch -- seat touch interface
release() -> 'None'
Request -- opcode 3 (attached to Resource instance)
Release the seat object
Using this request a client can tell the server that it is not going to use
the seat object anymore.
capabilities(capabilities: 'int') -> 'None'
Event -- opcode 0 (attached to Proxy instance)
Seat capabilities changed
This is emitted whenever a seat gains or loses the pointer, keyboard or
touch capabilities. The argument is a capability enum containing the
complete set of capabilities this seat has.
When the pointer capability is added, a client may create a WlPointer object
using the WlSeat.get_pointer() request. This object will receive pointer
events until the capability is removed in the future.
When the pointer capability is removed, a client should destroy the
WlPointer objects associated with the seat where the capability was removed,
using the WlPointer.release() request. No further pointer events will be
received on these objects.
In some compositors, if a seat regains the pointer capability and a client
has a previously obtained WlPointer object of version 4 or less, that object
may start sending pointer events again. This behavior is considered a
misinterpretation of the intended behavior and must not be relied upon by
the client. WlPointer objects of version 5 or later must not send events if
created before the most recent event notifying the client of an added
pointer capability.
The above behavior also applies to WlKeyboard and WlTouch with the keyboard
and touch capabilities, respectively.
Parameters
capabilities (ArgumentType.Uint) -- capabilities of the seat
name(name: 'str') -> 'None'
Event -- opcode 1 (attached to Proxy instance)
Unique identifier for this seat
In a multi-seat configuration the seat name can be used by clients to help
identify which physical devices the seat represents.
The seat name is a UTF-8 string with no convention defined for its contents.
Each name is unique among all WlSeat globals. The name is only guaranteed to
be unique for the current compositor instance.
The same seat names are used for all clients. Thus, the name can be shared
across processes to refer to a specific WlSeat global.
The name event is sent after binding to the seat global. This event is only
sent once per seat object, and the name does not change over the lifetime of
the WlSeat global.
Compositors may re-use the same seat name if the WlSeat global is destroyed
and re-created later.
Parameters
name (ArgumentType.String) -- seat identifier
WlShell
class pywayland.protocol.wayland.WlShell
Create desktop-style surfaces
This interface is implemented by servers that provide desktop-style user
interfaces.
It allows clients to associate a WlShellSurface with a basic surface.
Note! This protocol is deprecated and not intended for production use. For
desktop-style user interfaces, use xdg_shell. Compositors and clients should not
implement this interface.
get_shell_surface(surface: 'WlSurface') -> 'Proxy[WlShellSurface]'
Request -- opcode 0 (attached to Resource instance)
Create a shell surface from a surface
Create a shell surface for an existing surface. This gives the WlSurface the
role of a shell surface. If the WlSurface already has another role, it
raises a protocol error.
Only one shell surface can be associated with a given surface.
Parameters
surface (WlSurface) -- surface to be given the shell surface role
Returns
WlShellSurface -- shell surface to create
WlShellSurface
class pywayland.protocol.wayland.WlShellSurface
Desktop-style metadata interface
An interface that may be implemented by a WlSurface, for implementations that
provide a desktop-style user interface.
It provides requests to treat surfaces like toplevel, fullscreen or popup windows,
move, resize or maximize them, associate metadata like title and class, etc.
On the server side the object is automatically destroyed when the related WlSurface
is destroyed. On the client side, wl_shell_surface_destroy() must be called before
destroying the WlSurface object.
pong(serial: 'int') -> 'None'
Request -- opcode 0 (attached to Resource instance)
Respond to a ping event
A client must respond to a ping event with a pong request or the client may
be deemed unresponsive.
Parameters
serial (ArgumentType.Uint) -- serial number of the ping event
move(seat: 'WlSeat', serial: 'int') -> 'None'
Request -- opcode 1 (attached to Resource instance)
Start an interactive move
Start a pointer-driven move of the surface.
This request must be used in response to a button press event. The server
may ignore move requests depending on the state of the surface (e.g.
fullscreen or maximized).
Parameters
• seat (WlSeat) -- seat whose pointer is used
• serial (ArgumentType.Uint) -- serial number of the implicit grab on
the pointer
resize(seat: 'WlSeat', serial: 'int', edges: 'int') -> 'None'
Request -- opcode 2 (attached to Resource instance)
Start an interactive resize
Start a pointer-driven resizing of the surface.
This request must be used in response to a button press event. The server
may ignore resize requests depending on the state of the surface (e.g.
fullscreen or maximized).
Parameters
• seat (WlSeat) -- seat whose pointer is used
• serial (ArgumentType.Uint) -- serial number of the implicit grab on
the pointer
• edges (ArgumentType.Uint) -- which edge or corner is being dragged
set_toplevel() -> 'None'
Request -- opcode 3 (attached to Resource instance)
Make the surface a toplevel surface
Map the surface as a toplevel surface.
A toplevel surface is not fullscreen, maximized or transient.
set_transient(parent: 'WlSurface', x: 'int', y: 'int', flags: 'int') -> 'None'
Request -- opcode 4 (attached to Resource instance)
Make the surface a transient surface
Map the surface relative to an existing surface.
The x and y arguments specify the location of the upper left corner of the
surface relative to the upper left corner of the parent surface, in
surface-local coordinates.
The flags argument controls details of the transient behaviour.
Parameters
• parent (WlSurface) -- parent surface
• x (ArgumentType.Int) -- surface-local x coordinate
• y (ArgumentType.Int) -- surface-local y coordinate
• flags (ArgumentType.Uint) -- transient surface behavior
set_fullscreen(method: 'int', framerate: 'int', output: 'WlOutput | None') ->
'None'
Request -- opcode 5 (attached to Resource instance)
Make the surface a fullscreen surface
Map the surface as a fullscreen surface.
If an output parameter is given then the surface will be made fullscreen on
that output. If the client does not specify the output then the compositor
will apply its policy - usually choosing the output on which the surface has
the biggest surface area.
The client may specify a method to resolve a size conflict between the
output size and the surface size - this is provided through the method
parameter.
The framerate parameter is used only when the method is set to "driver", to
indicate the preferred framerate. A value of 0 indicates that the client
does not care about framerate. The framerate is specified in mHz, that is
framerate of 60000 is 60Hz.
A method of "scale" or "driver" implies a scaling operation of the surface,
either via a direct scaling operation or a change of the output mode. This
will override any kind of output scaling, so that mapping a surface with a
buffer size equal to the mode can fill the screen independent of
buffer_scale.
A method of "fill" means we don't scale up the buffer, however any output
scale is applied. This means that you may run into an edge case where the
application maps a buffer with the same size of the output mode but
buffer_scale 1 (thus making a surface larger than the output). In this case
it is allowed to downscale the results to fit the screen.
The compositor must reply to this request with a configure event with the
dimensions for the output on which the surface will be made fullscreen.
Parameters
• method (ArgumentType.Uint) -- method for resolving size conflict
• framerate (ArgumentType.Uint) -- framerate in mHz
• output (WlOutput or None) -- output on which the surface is to be
fullscreen
set_popup(seat: 'WlSeat', serial: 'int', parent: 'WlSurface', x: 'int', y: 'int',
flags: 'int') -> 'None'
Request -- opcode 6 (attached to Resource instance)
Make the surface a popup surface
Map the surface as a popup.
A popup surface is a transient surface with an added pointer grab.
An existing implicit grab will be changed to owner-events mode, and the
popup grab will continue after the implicit grab ends (i.e. releasing the
mouse button does not cause the popup to be unmapped).
The popup grab continues until the window is destroyed or a mouse button is
pressed in any other client's window. A click in any of the client's
surfaces is reported as normal, however, clicks in other clients' surfaces
will be discarded and trigger the callback.
The x and y arguments specify the location of the upper left corner of the
surface relative to the upper left corner of the parent surface, in
surface-local coordinates.
Parameters
• seat (WlSeat) -- seat whose pointer is used
• serial (ArgumentType.Uint) -- serial number of the implicit grab on
the pointer
• parent (WlSurface) -- parent surface
• x (ArgumentType.Int) -- surface-local x coordinate
• y (ArgumentType.Int) -- surface-local y coordinate
• flags (ArgumentType.Uint) -- transient surface behavior
set_maximized(output: 'WlOutput | None') -> 'None'
Request -- opcode 7 (attached to Resource instance)
Make the surface a maximized surface
Map the surface as a maximized surface.
If an output parameter is given then the surface will be maximized on that
output. If the client does not specify the output then the compositor will
apply its policy - usually choosing the output on which the surface has the
biggest surface area.
The compositor will reply with a configure event telling the expected new
surface size. The operation is completed on the next buffer attach to this
surface.
A maximized surface typically fills the entire output it is bound to, except
for desktop elements such as panels. This is the main difference between a
maximized shell surface and a fullscreen shell surface.
The details depend on the compositor implementation.
Parameters
output (WlOutput or None) -- output on which the surface is to be
maximized
set_title(title: 'str') -> 'None'
Request -- opcode 8 (attached to Resource instance)
Set surface title
Set a short title for the surface.
This string may be used to identify the surface in a task bar, window list,
or other user interface elements provided by the compositor.
The string must be encoded in UTF-8.
Parameters
title (ArgumentType.String) -- surface title
set_class(class_: 'str') -> 'None'
Request -- opcode 9 (attached to Resource instance)
Set surface class
Set a class for the surface.
The surface class identifies the general class of applications to which the
surface belongs. A common convention is to use the file name (or the full
path if it is a non-standard location) of the application's .desktop file as
the class.
Parameters
class (ArgumentType.String) -- surface class
ping(serial: 'int') -> 'None'
Event -- opcode 0 (attached to Proxy instance)
Ping client
Ping a client to check if it is receiving events and sending requests. A
client is expected to reply with a pong request.
Parameters
serial (ArgumentType.Uint) -- serial number of the ping
configure(edges: 'int', width: 'int', height: 'int') -> 'None'
Event -- opcode 1 (attached to Proxy instance)
Suggest resize
The configure event asks the client to resize its surface.
The size is a hint, in the sense that the client is free to ignore it if it
doesn't resize, pick a smaller size (to satisfy aspect ratio or resize in
steps of NxM pixels).
The edges parameter provides a hint about how the surface was resized. The
client may use this information to decide how to adjust its content to the
new size (e.g. a scrolling area might adjust its content position to leave
the viewable content unmoved).
The client is free to dismiss all but the last configure event it received.
The width and height arguments specify the size of the window in
surface-local coordinates.
Parameters
• edges (ArgumentType.Uint) -- how the surface was resized
• width (ArgumentType.Int) -- new width of the surface
• height (ArgumentType.Int) -- new height of the surface
popup_done() -> 'None'
Event -- opcode 2 (attached to Proxy instance)
Popup interaction is done
The popup_done event is sent out when a popup grab is broken, that is, when
the user clicks a surface that doesn't belong to the client owning the popup
surface.
WlShm
class pywayland.protocol.wayland.WlShm
Shared memory support
A singleton global object that provides support for shared memory.
Clients can create WlShmPool objects using the create_pool request.
On binding the WlShm object one or more format events are emitted to inform clients
about the valid pixel formats that can be used for buffers.
create_pool(fd: 'int', size: 'int') -> 'Proxy[WlShmPool]'
Request -- opcode 0 (attached to Resource instance)
Create a shm pool
Create a new WlShmPool object.
The pool can be used to create shared memory based buffer objects. The
server will mmap size bytes of the passed file descriptor, to use as backing
memory for the pool.
Parameters
• fd (ArgumentType.FileDescriptor) -- file descriptor for the pool
• size (ArgumentType.Int) -- pool size, in bytes
Returns
WlShmPool -- pool to create
release() -> 'None'
Request -- opcode 1 (attached to Resource instance)
Release the shm object
Using this request a client can tell the server that it is not going to use
the shm object anymore.
Objects created via this interface remain unaffected.
format(format: 'int') -> 'None'
Event -- opcode 0 (attached to Proxy instance)
Pixel format description
Informs the client about a valid pixel format that can be used for buffers.
Known formats include argb8888 and xrgb8888.
Parameters
format (ArgumentType.Uint) -- buffer pixel format
WlShmPool
class pywayland.protocol.wayland.WlShmPool
A shared memory pool
The WlShmPool object encapsulates a piece of memory shared between the compositor
and client. Through the WlShmPool object, the client can allocate shared memory
WlBuffer objects. All objects created through the same pool share the same
underlying mapped memory. Reusing the mapped memory avoids the setup/teardown
overhead and is useful when interactively resizing a surface or for many small
buffers.
create_buffer(offset: 'int', width: 'int', height: 'int', stride: 'int', format:
'int') -> 'Proxy[WlBuffer]'
Request -- opcode 0 (attached to Resource instance)
Create a buffer from the pool
Create a WlBuffer object from the pool.
The buffer is created offset bytes into the pool and has width and height as
specified. The stride argument specifies the number of bytes from the
beginning of one row to the beginning of the next. The format is the pixel
format of the buffer and must be one of those advertised through the
WlShm.format() event.
A buffer will keep a reference to the pool it was created from so it is
valid to destroy the pool immediately after creating a buffer from it.
Parameters
• offset (ArgumentType.Int) -- buffer byte offset within the pool
• width (ArgumentType.Int) -- buffer width, in pixels
• height (ArgumentType.Int) -- buffer height, in pixels
• stride (ArgumentType.Int) -- number of bytes from the beginning of
one row to the beginning of the next row
• format (ArgumentType.Uint) -- buffer pixel format
Returns
WlBuffer -- buffer to create
destroy() -> 'None'
Request -- opcode 1 (attached to Resource instance)
Destroy the pool
Destroy the shared memory pool.
The mmapped memory will be released when all buffers that have been created
from this pool are gone.
resize(size: 'int') -> 'None'
Request -- opcode 2 (attached to Resource instance)
Change the size of the pool mapping
This request will cause the server to remap the backing memory for the pool
from the file descriptor passed when the pool was created, but using the new
size. This request can only be used to make the pool bigger.
This request only changes the amount of bytes that are mmapped by the server
and does not touch the file corresponding to the file descriptor passed at
creation time. It is the client's responsibility to ensure that the file is
at least as big as the new pool size.
Parameters
size (ArgumentType.Int) -- new size of the pool, in bytes
WlSubcompositor
class pywayland.protocol.wayland.WlSubcompositor
Sub-surface compositing
The global interface exposing sub-surface compositing capabilities. A WlSurface,
that has sub-surfaces associated, is called the parent surface. Sub-surfaces can be
arbitrarily nested and create a tree of sub-surfaces.
The root surface in a tree of sub-surfaces is the main surface. The main surface
cannot be a sub-surface, because sub-surfaces must always have a parent.
A main surface with its sub-surfaces forms a (compound) window. For window
management purposes, this set of WlSurface objects is to be considered as a single
window, and it should also behave as such.
The aim of sub-surfaces is to offload some of the compositing work within a window
from clients to the compositor. A prime example is a video player with decorations
and video in separate WlSurface objects. This should allow the compositor to pass
YUV video buffer processing to dedicated overlay hardware when possible.
destroy() -> 'None'
Request -- opcode 0 (attached to Resource instance)
Unbind from the subcompositor interface
Informs the server that the client will not be using this protocol object
anymore. This does not affect any other objects, WlSubsurface objects
included.
get_subsurface(surface: 'WlSurface', parent: 'WlSurface') -> 'Proxy[WlSubsurface]'
Request -- opcode 1 (attached to Resource instance)
Give a surface the role sub-surface
Create a sub-surface interface for the given surface, and associate it with
the given parent surface. This turns a plain WlSurface into a sub-surface.
The to-be sub-surface must not already have another role, and it must not
have an existing WlSubsurface object. Otherwise the bad_surface protocol
error is raised.
Adding sub-surfaces to a parent is a double-buffered operation on the parent
(see WlSurface.commit()). The effect of adding a sub-surface becomes visible
on the next time the state of the parent surface is applied.
The parent surface must not be one of the child surface's descendants, and
the parent must be different from the child surface, otherwise the
bad_parent protocol error is raised.
This request modifies the behaviour of WlSurface.commit() request on the
sub- surface, see the documentation on WlSubsurface interface.
Parameters
• surface (WlSurface) -- the surface to be turned into a sub-surface
• parent (WlSurface) -- the parent surface
Returns
WlSubsurface -- the new sub- surface object ID
WlSubsurface
class pywayland.protocol.wayland.WlSubsurface
Sub-surface interface to a WlSurface
An additional interface to a WlSurface object, which has been made a sub-surface. A
sub-surface has one parent surface. A sub-surface's size and position are not
limited to that of the parent. Particularly, a sub-surface is not automatically
clipped to its parent's area.
A sub-surface becomes mapped, when a non-NULL WlBuffer is applied and the parent
surface is mapped. The order of which one happens first is irrelevant. A
sub-surface is hidden if the parent becomes hidden, or if a NULL WlBuffer is
applied. These rules apply recursively through the tree of surfaces.
The behaviour of a WlSurface.commit() request on a sub-surface depends on the
sub-surface's mode. The possible modes are synchronized and desynchronized, see
methods WlSubsurface.set_sync() and WlSubsurface.set_desync(). Synchronized mode
caches the WlSurface state to be applied when the parent's state gets applied, and
desynchronized mode applies the pending WlSurface state directly. A sub- surface is
initially in the synchronized mode.
Sub-surfaces also have another kind of state, which is managed by WlSubsurface
requests, as opposed to WlSurface requests. This state includes the sub-surface
position relative to the parent surface (WlSubsurface.set_position()), and the
stacking order of the parent and its sub-surfaces (WlSubsurface.place_above() and
.place_below). This state is applied when the parent surface's WlSurface state is
applied, regardless of the sub-surface's mode. As the exception, set_sync and
set_desync are effective immediately.
The main surface can be thought to be always in desynchronized mode, since it does
not have a parent in the sub-surfaces sense.
Even if a sub-surface is in desynchronized mode, it will behave as in synchronized
mode, if its parent surface behaves as in synchronized mode. This rule is applied
recursively throughout the tree of surfaces. This means, that one can set a
sub-surface into synchronized mode, and then assume that all its child and
grand-child sub-surfaces are synchronized, too, without explicitly setting them.
Destroying a sub-surface takes effect immediately. If you need to synchronize the
removal of a sub-surface to the parent surface update, unmap the sub-surface first
by attaching a NULL WlBuffer, update parent, and then destroy the sub-surface.
If the parent WlSurface object is destroyed, the sub-surface is unmapped.
A sub-surface never has the keyboard focus of any seat.
The WlSurface.offset() request is ignored: clients must use set_position instead to
move the sub-surface.
destroy() -> 'None'
Request -- opcode 0 (attached to Resource instance)
Remove sub-surface interface
The sub-surface interface is removed from the WlSurface object that was
turned into a sub-surface with a WlSubcompositor.get_subsurface() request.
The wl_surface's association to the parent is deleted. The WlSurface is
unmapped immediately.
set_position(x: 'int', y: 'int') -> 'None'
Request -- opcode 1 (attached to Resource instance)
Reposition the sub-surface
This schedules a sub-surface position change. The sub-surface will be moved
so that its origin (top left corner pixel) will be at the location x, y of
the parent surface coordinate system. The coordinates are not restricted to
the parent surface area. Negative values are allowed.
The scheduled coordinates will take effect whenever the state of the parent
surface is applied.
If more than one set_position request is invoked by the client before the
commit of the parent surface, the position of a new request always replaces
the scheduled position from any previous request.
The initial position is 0, 0.
Parameters
• x (ArgumentType.Int) -- x coordinate in the parent surface
• y (ArgumentType.Int) -- y coordinate in the parent surface
place_above(sibling: 'WlSurface') -> 'None'
Request -- opcode 2 (attached to Resource instance)
Restack the sub-surface
This sub-surface is taken from the stack, and put back just above the
reference surface, changing the z-order of the sub-surfaces. The reference
surface must be one of the sibling surfaces, or the parent surface. Using
any other surface, including this sub-surface, will cause a protocol error.
The z-order is double-buffered. Requests are handled in order and applied
immediately to a pending state. The final pending state is copied to the
active state the next time the state of the parent surface is applied.
A new sub-surface is initially added as the top-most in the stack of its
siblings and parent.
Parameters
sibling (WlSurface) -- the reference surface
place_below(sibling: 'WlSurface') -> 'None'
Request -- opcode 3 (attached to Resource instance)
Restack the sub-surface
The sub-surface is placed just below the reference surface. See
WlSubsurface.place_above().
Parameters
sibling (WlSurface) -- the reference surface
set_sync() -> 'None'
Request -- opcode 4 (attached to Resource instance)
Set sub-surface to synchronized mode
Change the commit behaviour of the sub-surface to synchronized mode, also
described as the parent dependent mode.
In synchronized mode, WlSurface.commit() on a sub-surface will accumulate
the committed state in a cache, but the state will not be applied and hence
will not change the compositor output. The cached state is applied to the
sub-surface immediately after the parent surface's state is applied. This
ensures atomic updates of the parent and all its synchronized sub-surfaces.
Applying the cached state will invalidate the cache, so further parent
surface commits do not (re-)apply old state.
See WlSubsurface for the recursive effect of this mode.
set_desync() -> 'None'
Request -- opcode 5 (attached to Resource instance)
Set sub-surface to desynchronized mode
Change the commit behaviour of the sub-surface to desynchronized mode, also
described as independent or freely running mode.
In desynchronized mode, WlSurface.commit() on a sub-surface will apply the
pending state directly, without caching, as happens normally with a
WlSurface. Calling WlSurface.commit() on the parent surface has no effect on
the sub-surface's WlSurface state. This mode allows a sub-surface to be
updated on its own.
If cached state exists when WlSurface.commit() is called in desynchronized
mode, the pending state is added to the cached state, and applied as a
whole. This invalidates the cache.
Note: even if a sub-surface is set to desynchronized, a parent sub- surface
may override it to behave as synchronized. For details, see WlSubsurface.
If a surface's parent surface behaves as desynchronized, then the cached
state is applied on set_desync.
WlSurface
class pywayland.protocol.wayland.WlSurface
An onscreen surface
A surface is a rectangular area that may be displayed on zero or more outputs, and
shown any number of times at the compositor's discretion. They can present
wl_buffers, receive user input, and define a local coordinate system.
The size of a surface (and relative positions on it) is described in surface-local
coordinates, which may differ from the buffer coordinates of the pixel content, in
case a buffer_transform or a buffer_scale is used.
A surface without a "role" is fairly useless: a compositor does not know where,
when or how to present it. The role is the purpose of a WlSurface. Examples of
roles are a cursor for a pointer (as set by WlPointer.set_cursor()), a drag icon (‐
WlDataDevice.start_drag()), a sub-surface (WlSubcompositor.get_subsurface()), and a
window as defined by a shell protocol (e.g. WlShell.get_shell_surface()).
A surface can have only one role at a time. Initially a WlSurface does not have a
role. Once a WlSurface is given a role, it is set permanently for the whole
lifetime of the WlSurface object. Giving the current role again is allowed, unless
explicitly forbidden by the relevant interface specification.
Surface roles are given by requests in other interfaces such as
WlPointer.set_cursor(). The request should explicitly mention that this request
gives a role to a WlSurface. Often, this request also creates a new protocol
object that represents the role and adds additional functionality to WlSurface.
When a client wants to destroy a WlSurface, they must destroy this role object
before the WlSurface, otherwise a defunct_role_object error is sent.
Destroying the role object does not remove the role from the WlSurface, but it may
stop the WlSurface from "playing the role". For instance, if a WlSubsurface object
is destroyed, the WlSurface it was created for will be unmapped and forget its
position and z-order. It is allowed to create a WlSubsurface for the same WlSurface
again, but it is not allowed to use the WlSurface as a cursor (cursor is a
different role than sub- surface, and role switching is not allowed).
destroy() -> 'None'
Request -- opcode 0 (attached to Resource instance)
Delete surface
Deletes the surface and invalidates its object ID.
attach(buffer: 'WlBuffer | None', x: 'int', y: 'int') -> 'None'
Request -- opcode 1 (attached to Resource instance)
Set the surface contents
Set a buffer as the content of this surface.
The new size of the surface is calculated based on the buffer size
transformed by the inverse buffer_transform and the inverse buffer_scale.
This means that at commit time the supplied buffer size must be an integer
multiple of the buffer_scale. If that's not the case, an invalid_size error
is sent.
The x and y arguments specify the location of the new pending buffer's upper
left corner, relative to the current buffer's upper left corner, in
surface-local coordinates. In other words, the x and y, combined with the
new surface size define in which directions the surface's size changes.
Setting anything other than 0 as x and y arguments is discouraged, and
should instead be replaced with using the separate WlSurface.offset()
request.
When the bound WlSurface version is 5 or higher, passing any non-zero x or y
is a protocol violation, and will result in an 'invalid_offset' error being
raised. The x and y arguments are ignored and do not change the pending
state. To achieve equivalent semantics, use WlSurface.offset().
Surface contents are double-buffered state, see WlSurface.commit().
The initial surface contents are void; there is no content.
WlSurface.attach() assigns the given WlBuffer as the pending WlBuffer.
WlSurface.commit() makes the pending WlBuffer the new surface contents, and
the size of the surface becomes the size calculated from the WlBuffer, as
described above. After commit, there is no pending buffer until the next
attach.
Committing a pending WlBuffer allows the compositor to read the pixels in
the WlBuffer. The compositor may access the pixels at any time after the
WlSurface.commit() request. When the compositor will not access the pixels
anymore, it will send the WlBuffer.release() event. Only after receiving
WlBuffer.release(), the client may reuse the WlBuffer. A WlBuffer that has
been attached and then replaced by another attach instead of committed will
not receive a release event, and is not used by the compositor.
If a pending WlBuffer has been committed to more than one WlSurface, the
delivery of WlBuffer.release() events becomes undefined. A well behaved
client should not rely on WlBuffer.release() events in this case.
Alternatively, a client could create multiple WlBuffer objects from the same
backing storage or use wp_linux_buffer_release.
Destroying the WlBuffer after WlBuffer.release() does not change the surface
contents. Destroying the WlBuffer before WlBuffer.release() is allowed as
long as the underlying buffer storage isn't re-used (this can happen e.g. on
client process termination). However, if the client destroys the WlBuffer
before receiving the WlBuffer.release() event and mutates the underlying
buffer storage, the surface contents become undefined immediately.
If WlSurface.attach() is sent with a NULL WlBuffer, the following
WlSurface.commit() will remove the surface content.
If a pending WlBuffer has been destroyed, the result is not specified. Many
compositors are known to remove the surface content on the following
WlSurface.commit(), but this behaviour is not universal. Clients seeking to
maximise compatibility should not destroy pending buffers and should ensure
that they explicitly remove content from surfaces, even after destroying
buffers.
Parameters
• buffer (WlBuffer or None) -- buffer of surface contents
• x (ArgumentType.Int) -- surface-local x coordinate
• y (ArgumentType.Int) -- surface-local y coordinate
damage(x: 'int', y: 'int', width: 'int', height: 'int') -> 'None'
Request -- opcode 2 (attached to Resource instance)
Mark part of the surface damaged
This request is used to describe the regions where the pending buffer is
different from the current surface contents, and where the surface therefore
needs to be repainted. The compositor ignores the parts of the damage that
fall outside of the surface.
Damage is double-buffered state, see WlSurface.commit().
The damage rectangle is specified in surface-local coordinates, where x and
y specify the upper left corner of the damage rectangle.
The initial value for pending damage is empty: no damage.
WlSurface.damage() adds pending damage: the new pending damage is the union
of old pending damage and the given rectangle.
WlSurface.commit() assigns pending damage as the current damage, and clears
pending damage. The server will clear the current damage as it repaints the
surface.
Note! New clients should not use this request. Instead damage can be posted
with WlSurface.damage_buffer() which uses buffer coordinates instead of
surface coordinates.
Parameters
• x (ArgumentType.Int) -- surface-local x coordinate
• y (ArgumentType.Int) -- surface-local y coordinate
• width (ArgumentType.Int) -- width of damage rectangle
• height (ArgumentType.Int) -- height of damage rectangle
frame() -> 'Proxy[WlCallback]'
Request -- opcode 3 (attached to Resource instance)
Request a frame throttling hint
Request a notification when it is a good time to start drawing a new frame,
by creating a frame callback. This is useful for throttling redrawing
operations, and driving animations.
When a client is animating on a WlSurface, it can use the 'frame' request to
get notified when it is a good time to draw and commit the next frame of
animation. If the client commits an update earlier than that, it is likely
that some updates will not make it to the display, and the client is wasting
resources by drawing too often.
The frame request will take effect on the next WlSurface.commit(). The
notification will only be posted for one frame unless requested again. For a
WlSurface, the notifications are posted in the order the frame requests were
committed.
The server must send the notifications so that a client will not send
excessive updates, while still allowing the highest possible update rate for
clients that wait for the reply before drawing again. The server should give
some time for the client to draw and commit after sending the frame callback
events to let it hit the next output refresh.
A server should avoid signaling the frame callbacks if the surface is not
visible in any way, e.g. the surface is off-screen, or completely obscured
by other opaque surfaces.
The object returned by this request will be destroyed by the compositor
after the callback is fired and as such the client must not attempt to use
it after that point.
The callback_data passed in the callback is the current time, in
milliseconds, with an undefined base.
Returns
WlCallback -- callback object for the frame request
set_opaque_region(region: 'WlRegion | None') -> 'None'
Request -- opcode 4 (attached to Resource instance)
Set opaque region
This request sets the region of the surface that contains opaque content.
The opaque region is an optimization hint for the compositor that lets it
optimize the redrawing of content behind opaque regions. Setting an opaque
region is not required for correct behaviour, but marking transparent
content as opaque will result in repaint artifacts.
The opaque region is specified in surface-local coordinates.
The compositor ignores the parts of the opaque region that fall outside of
the surface.
Opaque region is double-buffered state, see WlSurface.commit().
WlSurface.set_opaque_region() changes the pending opaque region.
WlSurface.commit() copies the pending region to the current region.
Otherwise, the pending and current regions are never changed.
The initial value for an opaque region is empty. Setting the pending opaque
region has copy semantics, and the WlRegion object can be destroyed
immediately. A NULL WlRegion causes the pending opaque region to be set to
empty.
Parameters
region (WlRegion or None) -- opaque region of the surface
set_input_region(region: 'WlRegion | None') -> 'None'
Request -- opcode 5 (attached to Resource instance)
Set input region
This request sets the region of the surface that can receive pointer and
touch events.
Input events happening outside of this region will try the next surface in
the server surface stack. The compositor ignores the parts of the input
region that fall outside of the surface.
The input region is specified in surface-local coordinates.
Input region is double-buffered state, see WlSurface.commit().
WlSurface.set_input_region() changes the pending input region.
WlSurface.commit() copies the pending region to the current region.
Otherwise the pending and current regions are never changed, except cursor
and icon surfaces are special cases, see WlPointer.set_cursor() and
WlDataDevice.start_drag().
The initial value for an input region is infinite. That means the whole
surface will accept input. Setting the pending input region has copy
semantics, and the WlRegion object can be destroyed immediately. A NULL
WlRegion causes the input region to be set to infinite.
Parameters
region (WlRegion or None) -- input region of the surface
commit() -> 'None'
Request -- opcode 6 (attached to Resource instance)
Commit pending surface state
Surface state (input, opaque, and damage regions, attached buffers, etc.) is
double-buffered. Protocol requests modify the pending state, as opposed to
the active state in use by the compositor.
A commit request atomically creates a content update from the pending state,
even if the pending state has not been touched. The content update is placed
in a queue until it becomes active. After commit, the new pending state is
as documented for each related request.
When the content update is applied, the WlBuffer is applied before all other
state. This means that all coordinates in double-buffered state are relative
to the newly attached wl_buffers, except for WlSurface.attach() itself. If
there is no newly attached WlBuffer, the coordinates are relative to the
previous content update.
All requests that need a commit to become effective are documented to affect
double-buffered state.
Other interfaces may add further double-buffered surface state.
set_buffer_transform(transform: 'int') -> 'None'
Request -- opcode 7 (attached to Resource instance)
Sets the buffer transformation
This request sets the transformation that the client has already applied to
the content of the buffer. The accepted values for the transform parameter
are the values for WlOutput.transform().
The compositor applies the inverse of this transformation whenever it uses
the buffer contents.
Buffer transform is double-buffered state, see WlSurface.commit().
A newly created surface has its buffer transformation set to normal.
WlSurface.set_buffer_transform() changes the pending buffer transformation.
WlSurface.commit() copies the pending buffer transformation to the current
one. Otherwise, the pending and current values are never changed.
The purpose of this request is to allow clients to render content according
to the output transform, thus permitting the compositor to use certain
optimizations even if the display is rotated. Using hardware overlays and
scanning out a client buffer for fullscreen surfaces are examples of such
optimizations. Those optimizations are highly dependent on the compositor
implementation, so the use of this request should be considered on a
case-by-case basis.
Note that if the transform value includes 90 or 270 degree rotation, the
width of the buffer will become the surface height and the height of the
buffer will become the surface width.
If transform is not one of the values from the WlOutput.transform() enum the
invalid_transform protocol error is raised.
Parameters
transform (ArgumentType.Int) -- transform for interpreting buffer
contents
set_buffer_scale(scale: 'int') -> 'None'
Request -- opcode 8 (attached to Resource instance)
Sets the buffer scaling factor
This request sets an optional scaling factor on how the compositor
interprets the contents of the buffer attached to the window.
Buffer scale is double-buffered state, see WlSurface.commit().
A newly created surface has its buffer scale set to 1.
WlSurface.set_buffer_scale() changes the pending buffer scale.
WlSurface.commit() copies the pending buffer scale to the current one.
Otherwise, the pending and current values are never changed.
The purpose of this request is to allow clients to supply higher resolution
buffer data for use on high resolution outputs. It is intended that you pick
the same buffer scale as the scale of the output that the surface is
displayed on. This means the compositor can avoid scaling when rendering the
surface on that output.
Note that if the scale is larger than 1, then you have to attach a buffer
that is larger (by a factor of scale in each dimension) than the desired
surface size.
If scale is not greater than 0 the invalid_scale protocol error is raised.
Parameters
scale (ArgumentType.Int) -- scale for interpreting buffer contents
damage_buffer(x: 'int', y: 'int', width: 'int', height: 'int') -> 'None'
Request -- opcode 9 (attached to Resource instance)
Mark part of the surface damaged using buffer coordinates
This request is used to describe the regions where the pending buffer is
different from the current surface contents, and where the surface therefore
needs to be repainted. The compositor ignores the parts of the damage that
fall outside of the surface.
Damage is double-buffered state, see WlSurface.commit().
The damage rectangle is specified in buffer coordinates, where x and y
specify the upper left corner of the damage rectangle.
The initial value for pending damage is empty: no damage.
WlSurface.damage_buffer() adds pending damage: the new pending damage is the
union of old pending damage and the given rectangle.
WlSurface.commit() assigns pending damage as the current damage, and clears
pending damage. The server will clear the current damage as it repaints the
surface.
This request differs from WlSurface.damage() in only one way - it takes
damage in buffer coordinates instead of surface-local coordinates. While
this generally is more intuitive than surface coordinates, it is especially
desirable when using wp_viewport or when a drawing library (like EGL) is
unaware of buffer scale and buffer transform.
Note: Because buffer transformation changes and damage requests may be
interleaved in the protocol stream, it is impossible to determine the actual
mapping between surface and buffer damage until WlSurface.commit() time.
Therefore, compositors wishing to take both kinds of damage into account
will have to accumulate damage from the two requests separately and only
transform from one to the other after receiving the WlSurface.commit().
Parameters
• x (ArgumentType.Int) -- buffer-local x coordinate
• y (ArgumentType.Int) -- buffer-local y coordinate
• width (ArgumentType.Int) -- width of damage rectangle
• height (ArgumentType.Int) -- height of damage rectangle
offset(x: 'int', y: 'int') -> 'None'
Request -- opcode 10 (attached to Resource instance)
Set the surface contents offset
The x and y arguments specify the location of the new pending buffer's upper
left corner, relative to the current buffer's upper left corner, in
surface-local coordinates. In other words, the x and y, combined with the
new surface size define in which directions the surface's size changes.
Surface location offset is double-buffered state, see WlSurface.commit().
This request is semantically equivalent to and the replaces the x and y
arguments in the WlSurface.attach() request in WlSurface versions prior to
5. See WlSurface.attach() for details.
Parameters
• x (ArgumentType.Int) -- surface-local x coordinate
• y (ArgumentType.Int) -- surface-local y coordinate
enter(output: 'WlOutput') -> 'None'
Event -- opcode 0 (attached to Proxy instance)
Surface enters an output
This is emitted whenever a surface's creation, movement, or resizing results
in some part of it being within the scanout region of an output.
Note that a surface may be overlapping with zero or more outputs.
Parameters
output (WlOutput) -- output entered by the surface
leave(output: 'WlOutput') -> 'None'
Event -- opcode 1 (attached to Proxy instance)
Surface leaves an output
This is emitted whenever a surface's creation, movement, or resizing results
in it no longer having any part of it within the scanout region of an
output.
Clients should not use the number of outputs the surface is on for frame
throttling purposes. The surface might be hidden even if no leave event has
been sent, and the compositor might expect new surface content updates even
if no enter event has been sent. The frame event should be used instead.
Parameters
output (WlOutput) -- output left by the surface
preferred_buffer_scale(factor: 'int') -> 'None'
Event -- opcode 2 (attached to Proxy instance)
Preferred buffer scale for the surface
This event indicates the preferred buffer scale for this surface. It is sent
whenever the compositor's preference changes.
Before receiving this event the preferred buffer scale for this surface is
1.
It is intended that scaling aware clients use this event to scale their
content and use WlSurface.set_buffer_scale() to indicate the scale they have
rendered with. This allows clients to supply a higher detail buffer.
The compositor shall emit a scale value greater than 0.
Parameters
factor (ArgumentType.Int) -- preferred scaling factor
preferred_buffer_transform(transform: 'int') -> 'None'
Event -- opcode 3 (attached to Proxy instance)
Preferred buffer transform for the surface
This event indicates the preferred buffer transform for this surface. It is
sent whenever the compositor's preference changes.
Before receiving this event the preferred buffer transform for this surface
is normal.
Applying this transformation to the surface buffer contents and using
WlSurface.set_buffer_transform() might allow the compositor to use the
surface buffer more efficiently.
Parameters
transform (ArgumentType.Uint) -- preferred transform
WlTouch
class pywayland.protocol.wayland.WlTouch
Touchscreen input device
The WlTouch interface represents a touchscreen associated with a seat.
Touch interactions can consist of one or more contacts. For each contact, a series
of events is generated, starting with a down event, followed by zero or more motion
events, and ending with an up event. Events relating to the same contact point can
be identified by the ID of the sequence.
release() -> 'None'
Request -- opcode 0 (attached to Resource instance)
Release the touch object
down(serial: 'int', time: 'int', surface: 'WlSurface', id: 'int', x: 'float', y:
'float') -> 'None'
Event -- opcode 0 (attached to Proxy instance)
Touch down event and beginning of a touch sequence
A new touch point has appeared on the surface. This touch point is assigned
a unique ID. Future events from this touch point reference this ID. The ID
ceases to be valid after a touch up event and may be reused in the future.
Parameters
• serial (ArgumentType.Uint) -- serial number of the touch down event
• time (ArgumentType.Uint) -- timestamp with millisecond granularity
• surface (WlSurface) -- surface touched
• id (ArgumentType.Int) -- the unique ID of this touch point
• x (ArgumentType.Fixed) -- surface-local x coordinate
• y (ArgumentType.Fixed) -- surface-local y coordinate
up(serial: 'int', time: 'int', id: 'int') -> 'None'
Event -- opcode 1 (attached to Proxy instance)
End of a touch event sequence
The touch point has disappeared. No further events will be sent for this
touch point and the touch point's ID is released and may be reused in a
future touch down event.
Parameters
• serial (ArgumentType.Uint) -- serial number of the touch up event
• time (ArgumentType.Uint) -- timestamp with millisecond granularity
• id (ArgumentType.Int) -- the unique ID of this touch point
motion(time: 'int', id: 'int', x: 'float', y: 'float') -> 'None'
Event -- opcode 2 (attached to Proxy instance)
Update of touch point coordinates
A touch point has changed coordinates.
Parameters
• time (ArgumentType.Uint) -- timestamp with millisecond granularity
• id (ArgumentType.Int) -- the unique ID of this touch point
• x (ArgumentType.Fixed) -- surface-local x coordinate
• y (ArgumentType.Fixed) -- surface-local y coordinate
frame() -> 'None'
Event -- opcode 3 (attached to Proxy instance)
End of touch frame event
Indicates the end of a set of events that logically belong together. A
client is expected to accumulate the data in all events within the frame
before proceeding.
A WlTouch.frame() terminates at least one event but otherwise no guarantee
is provided about the set of events within a frame. A client must assume
that any state not updated in a frame is unchanged from the previously known
state.
cancel() -> 'None'
Event -- opcode 4 (attached to Proxy instance)
Touch session cancelled
Sent if the compositor decides the touch stream is a global gesture. No
further events are sent to the clients from that particular gesture. Touch
cancellation applies to all touch points currently active on this client's
surface. The client is responsible for finalizing the touch points, future
touch points on this surface may reuse the touch point ID.
No frame event is required after the cancel event.
shape(id: 'int', major: 'float', minor: 'float') -> 'None'
Event -- opcode 5 (attached to Proxy instance)
Update shape of touch point
Sent when a touchpoint has changed its shape.
This event does not occur on its own. It is sent before a WlTouch.frame()
event and carries the new shape information for any previously reported, or
new touch points of that frame.
Other events describing the touch point such as WlTouch.down(),
WlTouch.motion() or WlTouch.orientation() may be sent within the same
WlTouch.frame(). A client should treat these events as a single logical
touch point update. The order of WlTouch.shape(), WlTouch.orientation() and
WlTouch.motion() is not guaranteed. A WlTouch.down() event is guaranteed to
occur before the first WlTouch.shape() event for this touch ID but both
events may occur within the same WlTouch.frame().
A touchpoint shape is approximated by an ellipse through the major and minor
axis length. The major axis length describes the longer diameter of the
ellipse, while the minor axis length describes the shorter diameter. Major
and minor are orthogonal and both are specified in surface-local
coordinates. The center of the ellipse is always at the touchpoint location
as reported by WlTouch.down() or WlTouch.move().
This event is only sent by the compositor if the touch device supports shape
reports. The client has to make reasonable assumptions about the shape if it
did not receive this event.
Parameters
• id (ArgumentType.Int) -- the unique ID of this touch point
• major (ArgumentType.Fixed) -- length of the major axis in
surface-local coordinates
• minor (ArgumentType.Fixed) -- length of the minor axis in
surface-local coordinates
orientation(id: 'int', orientation: 'float') -> 'None'
Event -- opcode 6 (attached to Proxy instance)
Update orientation of touch point
Sent when a touchpoint has changed its orientation.
This event does not occur on its own. It is sent before a WlTouch.frame()
event and carries the new shape information for any previously reported, or
new touch points of that frame.
Other events describing the touch point such as WlTouch.down(),
WlTouch.motion() or WlTouch.shape() may be sent within the same
WlTouch.frame(). A client should treat these events as a single logical
touch point update. The order of WlTouch.shape(), WlTouch.orientation() and
WlTouch.motion() is not guaranteed. A WlTouch.down() event is guaranteed to
occur before the first WlTouch.orientation() event for this touch ID but
both events may occur within the same WlTouch.frame().
The orientation describes the clockwise angle of a touchpoint's major axis
to the positive surface y-axis and is normalized to the -180 to +180 degree
range. The granularity of orientation depends on the touch device, some
devices only support binary rotation values between 0 and 90 degrees.
This event is only sent by the compositor if the touch device supports
orientation reports.
Parameters
• id (ArgumentType.Int) -- the unique ID of this touch point
• orientation (ArgumentType.Fixed) -- angle between major axis and
positive surface y-axis in degrees
Scanner Modules
Argumet
class pywayland.scanner.argument.Argument(name: str, type: ArgumentType, summary: str |
None, interface: str | None, allow_null: bool, enum: str | None, description: Description
| None)
Argument to a request or event method
Required attributes: name and type
Optional attributes: summary, interface, and allow-null
Child elements: description
property argument: str
Output as an Argument
property interface_class: str
Returns the Interface class name
Gives the class name for the Interface coresponding to the type of the
argument.
output_doc_param(printer: Printer) -> None
Document the argument as a parameter
output_doc_ret(printer: Printer) -> None
Document the argument as a return
property signature: str
Output as the argument appears in the signature.
class pywayland.scanner.argument.ArgumentType(value, names=<not given>, *values,
module=None, qualname=None, type=None, start=1, boundary=None)
Entry
class pywayland.scanner.entry.Entry(name: str, value: str, summary: str | None, since: str
| None, description: Description | None)
Scanner for enum entries
Required attributes: name and value
Optional attributes: summary and since
Child elements: description
output(enum_name: str, printer: Printer) -> None
Generate the output for the entry in the enum
Enum
class pywayland.scanner.enum.Enum(name: str, since: str | None, is_bitfield: bool,
description: Description | None, entry: list[Entry])
Scanner for enum objects
Required attributes: name and since
Child elements: description and entry
output(printer: Printer) -> None
Generate the output for the enum to the printer
Event
class pywayland.scanner.event.Event(name: str, since: str | None, description: Description
| None, arg: list[Argument])
Scanner for event objects (server-side method)
Required attributes: name
Optional attributes: since
Child elements: description and arg`
property method_args: Iterator[str]
Generator of the arguments to the method
All arguments to be sent to ._post_event must be passed in
output_body(printer: Printer, opcode: int) -> None
Output the body of the event to the printer
output_doc_params(printer: Printer) -> None
Aguments documented as parameters
All arguments are event parameters.
Interface
class pywayland.scanner.interface.Interface(name: 'str', version: 'str', description:
'Description | None', enum: 'list[Enum]', event: 'list[Event]', request: 'list[Request]')
property class_name: str
Returns the name of the class of the interface
Camel cases the name of the interface, to be used as the class name.
output(printer: Printer, module_imports: dict[str, str]) -> None
Generate the output for the interface to the printer
classmethod parse(element: Element) -> Interface
Scanner for interface objects
Required attributes: name and version
Child elements: description, request, event, enum
Method
class pywayland.scanner.method.Method(name: str, since: str | None, description:
Description | None, arg: list[Argument])
Scanner for methods
Corresponds to event and requests defined on an interface
imports(interface: str, module_imports: dict[str, str]) -> list[tuple[str, str]]
Get the imports required for each of the interfaces
Parameters
• interface -- The name of the interface that the method is a part
of.
• module_imports -- A mapping from the name of an interface in the
associated module that the interface comes from.
Returns
A list of 2-tuples, each specifying the path to an imported module
and the imported class.
output(printer: Printer, opcode: int, in_class: str, module_imports: dict[str,
str]) -> None
Generate the output for the given method to the printer
output_doc(printer: Printer) -> None
Output the documentation for the interface
Printer
Request
class pywayland.scanner.request.Request(name: str, since: str | None, description:
Description | None, arg: list[Argument], type: str | None)
Scanner for request objects (client-side method)
Required attributes: name
Optional attributes: type and since
Child elements: description and arg
property marshal_args: Iterable[str]
Arguments sent to ._marshal
property method_args: Iterable[str]
Generator of the arguments to the method
The new_id args are generated in marshaling the args, they do not appear in
the args of the method.
output_body(printer: Printer, opcode: int) -> None
Output the body of the request to the printer
output_doc_params(printer: Printer) -> None
Aguments documented as parameters
Anything that is not a new_id is
output_doc_ret(printer: Printer) -> None
Aguments documented as return values
Arguments of type new_id are returned from requests.
property return_type: str
The return type for the request.
Scanner
Using the Scanner module
The PyWayland scanner allows you to generate the protocol scanner output within Python
scripts. The general procedure to invoke the scanner will be to make a Protocol object,
scan the input file, and have the Protocol output to a directory. These steps are done
as:
Protocol.parse_file(path_to_xml_file)
Protocol.output(path_to_output_dir, {})
See the definitions below for more information on using Protocol objects.
Protocol Module
class pywayland.scanner.Protocol(name: str, copyright: Copyright | None, description:
Description | None, interface: list[Interface])
Protocol scanner object
Main scanner object that acts on the input xml files to generate protocol files.
Required attributes: name
Child elements: copyright?, description?, and interface+
Parameters
input_file -- Name of input XML file
output(output_dir: str, module_imports: dict[str, str]) -> None
Output the scanned files to the given directory
Parameters
output_dir (string) -- Path of directory to output protocol files to
Utilities Module
AnonymousFile Class
class pywayland.utils.AnonymousFile(size: int)
Anonymous file object
Provides access to anonymous file objects that can be used by Wayland clients to
render to surfaces. Uses a method similar to Weston to open an anonymous file, so
XDG_RUNTIME_DIR must be set for this to work properly.
This class provides a content manager, that is, it can be used with Python with
statements, where the value returned is the file descriptor.
close() -> None
Close the anonymous file
Closes the file descriptor and sets the fd property to None. Does nothing
if the file is not open.
open() -> None
Open an anonymous file
Opens the anonymous file and sets the fd property to the file descriptor
that has been opened.
AUTHOR
Sean Vig
COPYRIGHT
2024, Sean Vig