Enum Event

#[non_exhaustive]
pub enum Event<'a> {
    PreferredChanged {
        identity: u32,
    },
    PreferredChanged2 {
        identity_hi: u32,
        identity_lo: u32,
    },
}

Available on crate feature wayland and Linux only.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

PreferredChanged

the preferred image description changed (32-bit)

Starting from interface version 2, ‘preferred_changed2’ is sent instead of this event. See the ‘preferred_changed2’ event for the definition.

Fields

identity: u32

the 32-bit image description id number

PreferredChanged2

the preferred image description changed

The preferred image description is the one which likely has the most performance and/or quality benefits for the compositor if used by the client for its wl_surface contents. This event is sent whenever the compositor changes the wl_surface’s preferred image description.

This event sends the identity of the new preferred state as the argument, so clients who are aware of the image description already can reuse it. Otherwise, if the client client wants to know what the preferred image description is, it shall use the get_preferred request.

The preferred image description is not automatically used for anything. It is only a hint, and clients may set any valid image description with set_image_description, but there might be performance and color accuracy improvements by providing the wl_surface contents in the preferred image description. Therefore clients that can, should render according to the preferred image description

Only available since version 2 of the interface

Fields

identity_hi: u32

high 32 bits of the 64-bit image description id number

identity_lo: u32

low 32 bits of the 64-bit image description id number

Implementations

impl<'a> Event<'a>

pub fn opcode(&self) -> u16

Get the opcode number of this message

Trait Implementations

impl<'a> Debug for Event<'a>

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

Formats the value using the given formatter.