Enum Request

#[non_exhaustive]
pub enum Request<'a> {
    SetBarrier,
    WaitBarrier,
    Destroy,
}

Available on crate features staging and client 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.

SetBarrier

sets the start point for a fifo constraint

When the content update containing the “set_barrier” is applied, it sets a “fifo_barrier” condition on the surface associated with the fifo object. The condition is cleared immediately after the following latching deadline for non-tearing presentation.

The compositor may clear the condition early if it must do so to ensure client forward progress assumptions.

To wait for this condition to clear, use the “wait_barrier” request.

“set_barrier” is double-buffered state, see wl_surface.commit.

Requesting set_barrier after the fifo object’s surface is destroyed will generate a “surface_destroyed” error.

WaitBarrier

adds a fifo constraint to a content update

Indicate that this content update is not ready while a “fifo_barrier” condition is present on the surface.

This means that when the content update containing “set_barrier” was made active at a latching deadline, it will be active for at least one refresh cycle. A content update which is allowed to tear might become active after a latching deadline if no content update became active at the deadline.

The constraint must be ignored if the surface is a subsurface in synchronized mode. If the surface is not being updated by the compositor (off-screen, occluded) the compositor may ignore the constraint. Clients must use an additional mechanism such as frame callbacks or timestamps to ensure throttling occurs under all conditions.

“wait_barrier” is double-buffered state, see wl_surface.commit.

Requesting “wait_barrier” after the fifo object’s surface is destroyed will generate a “surface_destroyed” error.

Destroy

destroy the fifo interface

Informs the server that the client will no longer be using this protocol object.

Surface state changes previously made by this protocol are unaffected by this object’s destruction.

This is a destructor, once sent this object cannot be used any longer.

Implementations

impl<'a> Request<'a>

pub fn opcode(&self) -> u16

Get the opcode number of this message

Trait Implementations

impl<'a> Debug for Request<'a>

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

Formats the value using the given formatter.