Struct wayland_protocols::wp::viewporter::server::wp_viewport::WpViewport

pub struct WpViewport { /* private fields */ }

crop and scale interface to a wl_surface

An additional interface to a wl_surface object, which allows the client to specify the cropping and scaling of the surface contents.

This interface works with two concepts: the source rectangle (src_x, src_y, src_width, src_height), and the destination size (dst_width, dst_height). The contents of the source rectangle are scaled to the destination size, and content outside the source rectangle is ignored. This state is double-buffered, see wl_surface.commit.

The two parts of crop and scale state are independent: the source rectangle, and the destination size. Initially both are unset, that is, no scaling is applied. The whole of the current wl_buffer is used as the source, and the surface size is as defined in wl_surface.attach.

If the destination size is set, it causes the surface size to become dst_width, dst_height. The source (rectangle) is scaled to exactly this size. This overrides whatever the attached wl_buffer size is, unless the wl_buffer is NULL. If the wl_buffer is NULL, the surface has no content and therefore no size. Otherwise, the size is always at least 1x1 in surface local coordinates.

If the source rectangle is set, it defines what area of the wl_buffer is taken as the source. If the source rectangle is set and the destination size is not set, then src_width and src_height must be integers, and the surface size becomes the source rectangle size. This results in cropping without scaling. If src_width or src_height are not integers and destination size is not set, the bad_size protocol error is raised when the surface state is applied.

The coordinate transformations from buffer pixel coordinates up to the surface-local coordinates happen in the following order:

1. buffer_transform (wl_surface.set_buffer_transform)
2. buffer_scale (wl_surface.set_buffer_scale)
3. crop and scale (wp_viewport.set*) This means, that the source rectangle coordinates of crop and scale are given in the coordinates after the buffer transform and scale, i.e. in the coordinates that would be the surface-local coordinates if the crop and scale was not applied.

If src_x or src_y are negative, the bad_value protocol error is raised. Otherwise, if the source rectangle is partially or completely outside of the non-NULL wl_buffer, then the out_of_buffer protocol error is raised when the surface state is applied. A NULL wl_buffer does not raise the out_of_buffer error.

If the wl_surface associated with the wp_viewport is destroyed, all wp_viewport requests except ‘destroy’ raise the protocol error no_surface.

If the wp_viewport object is destroyed, the crop and scale state is removed from the wl_surface. The change will be applied on the next wl_surface.commit.

See also the Request enum for this interface.

Trait Implementations

impl Borrow<ObjectId> for WpViewport

fn borrow(&self) -> &ObjectId

Immutably borrows from an owned value.

impl Clone for WpViewport

fn clone(&self) -> WpViewport

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for WpViewport

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

Formats the value using the given formatter.

impl Hash for WpViewport

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<WpViewport>> for WpViewport

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

fn eq(&self, other: &WpViewport) -> 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 WpViewport

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 WpViewport