Struct WlSurface

pub struct WlSurface { /* private fields */ }

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 wl_surface. Examples of roles are a cursor for a pointer (as set by wl_pointer.set_cursor), a drag icon (wl_data_device.start_drag), a sub-surface (wl_subcompositor.get_subsurface), and a window as defined by a shell protocol (e.g. wl_shell.get_shell_surface).

A surface can have only one role at a time. Initially a wl_surface does not have a role. Once a wl_surface is given a role, it is set permanently for the whole lifetime of the wl_surface 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 wl_pointer.set_cursor. The request should explicitly mention that this request gives a role to a wl_surface. Often, this request also creates a new protocol object that represents the role and adds additional functionality to wl_surface. When a client wants to destroy a wl_surface, they must destroy this role object before the wl_surface, otherwise a defunct_role_object error is sent.

Destroying the role object does not remove the role from the wl_surface, but it may stop the wl_surface from “playing the role”. For instance, if a wl_subsurface object is destroyed, the wl_surface it was created for will be unmapped and forget its position and z-order. It is allowed to create a wl_subsurface for the same wl_surface again, but it is not allowed to use the wl_surface as a cursor (cursor is a different role than sub-surface, and role switching is not allowed).

See also the Request enum for this interface.

Implementations

impl WlSurface

pub fn enter(&self, output: &WlOutput)

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.

pub fn leave(&self, output: &WlOutput)

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.

pub fn preferred_buffer_scale(&self, factor: i32)

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 wl_surface.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.

pub fn preferred_buffer_transform(&self, transform: Transform)

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 wl_surface.set_buffer_transform might allow the compositor to use the surface buffer more efficiently.

Trait Implementations

impl Borrow<ObjectId> for WlSurface

fn borrow(&self) -> &ObjectId

Immutably borrows from an owned value.

impl Clone for WlSurface

fn clone(&self) -> WlSurface

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for WlSurface

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Hash for WlSurface

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq<Weak<WlSurface>> for WlSurface

fn eq(&self, other: &Weak<WlSurface>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialEq for WlSurface

fn eq(&self, other: &WlSurface) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Resource for WlSurface

type Request = Request

The request enum for this interface

type Event<'event> = Event<'event>

The event enum for this interface

fn interface() -> &'static Interface

The interface description

fn id(&self) -> ObjectId

The ID of this object

fn version(&self) -> u32

The version of this object

fn data<U: 'static>(&self) -> Option<&U>

Access the user-data associated with this object

fn object_data(&self) -> Option<&Arc<dyn Any + Send + Sync>>

Access the raw data associated with this object.

fn handle(&self) -> &WeakHandle

Access the backend handle associated with this object

fn from_id(conn: &DisplayHandle, id: ObjectId) -> Result<Self, InvalidId>

Create an object resource from its ID

fn send_event(&self, evt: Self::Event<'_>) -> Result<(), InvalidId>

Send an event to this object

fn parse_request( conn: &DisplayHandle, msg: Message<ObjectId, OwnedFd>, ) -> Result<(Self, Self::Request), DispatchError>

Parse a event for this object

fn write_event<'a>( &self, conn: &DisplayHandle, msg: Self::Event<'a>, ) -> Result<Message<ObjectId, BorrowedFd<'a>>, InvalidId>

Serialize an event for this object

fn client(&self) -> Option<Client>

The client owning this object

fn is_alive(&self) -> bool

Checks if the Wayland object associated with this proxy is still alive

fn post_error(&self, code: impl Into<u32>, error: impl Into<String>)

Trigger a protocol error on this object

fn downgrade(&self) -> Weak<Self>

Creates a weak handle to this object

impl Eq for WlSurface