Enum BarrierRequirement 

pub enum BarrierRequirement {
    Global,
    PaddedLocal(PaddingRect),
    Absolute(PxRect),
}

Defines the sampling requirements for a rendering command that needs a barrier.

Variants

Global

The command needs to sample from the entire previously rendered scene. This will cause a full-screen texture copy.

PaddedLocal(PaddingRect)

The command needs to sample from a region relative to its own bounding box.

• Sampling padding: The region from which pixels are read (e.g., blur needs to read pixels outside the target area). This determines the texture region captured before the command executes, while the write target remains the component’s measured size.

For most cases without special batching requirements, set a uniform padding value. For effects like blur that need large sampling areas but have small target areas, use large sampling padding so enough source pixels are available while batching still relies on the component’s bounds.

Examples

Simple case (uniform sampling padding):

use tessera_ui::renderer::command::{BarrierRequirement, PaddingRect};
use tessera_ui::Px;

let req = BarrierRequirement::PaddedLocal(PaddingRect::uniform(Px(10)));
let _ = req;

Blur optimization (large sampling area):

use tessera_ui::renderer::command::{BarrierRequirement, PaddingRect};
use tessera_ui::Px;

let req = BarrierRequirement::PaddedLocal(PaddingRect::uniform(Px(75)));
let _ = req;

Absolute(PxRect)

The command needs to sample from a specific, absolute region of the screen.

Implementations

impl BarrierRequirement

pub const ZERO_PADDING_LOCAL: Self

pub const fn uniform_padding_local(padding: Px) -> Self

Creates a PaddedLocal barrier requirement with uniform sampling padding on all sides.

Trait Implementations

impl Clone for BarrierRequirement

fn clone(&self) -> BarrierRequirement

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for BarrierRequirement

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

Formats the value using the given formatter.

impl PartialEq for BarrierRequirement

fn eq(&self, other: &BarrierRequirement) -> 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 Copy for BarrierRequirement

impl StructuralPartialEq for BarrierRequirement