Struct wayland_protocols::wp::presentation_time::server::wp_presentation::WpPresentation

pub struct WpPresentation { /* private fields */ }

Available on crate feature server only.

timed presentation related wl_surface requests

The main feature of this interface is accurate presentation timing feedback to ensure smooth video playback while maintaining audio/video synchronization. Some features use the concept of a presentation clock, which is defined in the presentation.clock_id event.

A content update for a wl_surface is submitted by a wl_surface.commit request. Request ‘feedback’ associates with the wl_surface.commit and provides feedback on the content update, particularly the final realized presentation time.

When the final realized presentation time is available, e.g. after a framebuffer flip completes, the requested presentation_feedback.presented events are sent. The final presentation time can differ from the compositor’s predicted display update time and the update’s target time, especially when the compositor misses its target vertical blanking period.

See also the Request enum for this interface.

Implementations

impl WpPresentation

pub fn clock_id(&self, clk_id: u32)

clock ID for timestamps

This event tells the client in which clock domain the compositor interprets the timestamps used by the presentation extension. This clock is called the presentation clock.

The compositor sends this event when the client binds to the presentation interface. The presentation clock does not change during the lifetime of the client connection.

The clock identifier is platform dependent. On Linux/glibc, the identifier value is one of the clockid_t values accepted by clock_gettime(). clock_gettime() is defined by POSIX.1-2001.

Timestamps in this clock domain are expressed as tv_sec_hi, tv_sec_lo, tv_nsec triples, each component being an unsigned 32-bit value. Whole seconds are in tv_sec which is a 64-bit value combined from tv_sec_hi and tv_sec_lo, and the additional fractional part in tv_nsec as nanoseconds. Hence, for valid timestamps tv_nsec must be in [0, 999999999].

Note that clock_id applies only to the presentation clock, and implies nothing about e.g. the timestamps used in the Wayland core protocol input events.

Compositors should prefer a clock which does not jump and is not slewed e.g. by NTP. The absolute value of the clock is irrelevant. Precision of one millisecond or better is recommended. Clients must be able to query the current clock value directly, not by asking the compositor.

Trait Implementations

impl Borrow<ObjectId> for WpPresentation

fn borrow(&self) -> &ObjectId

Immutably borrows from an owned value.

impl Clone for WpPresentation

fn clone(&self) -> WpPresentation

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for WpPresentation

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

Formats the value using the given formatter.

impl Hash for WpPresentation

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<WpPresentation>> for WpPresentation

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

This method tests for self and other values to be equal, and is used by ==.

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

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

impl PartialEq<WpPresentation> for WpPresentation

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

This method tests for self and other values to be equal, and is used by ==.

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

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

impl Resource for WpPresentation

type Request = Request

The request enum for this interface

type 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( &self, conn: &DisplayHandle, msg: Self::Event ) -> Result<Message<ObjectId, RawFd>, 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 WpPresentation