Struct ClipStackSnapshot

Source

pub struct ClipStackSnapshot { /* private fields */ }

Expand description

Immutable view of the active clip stack for one paint layer.

Entry order is outermost to innermost. Snapshots own a cloned vector and do not change if the originating ClipStack is later mutated.

§Examples

use ailloli_ui_runtime::scene::ClipStackSnapshot;
let snapshot = ClipStackSnapshot::empty();
assert!(snapshot.entries().is_empty());

Implementations§

Source §

impl ClipStackSnapshot

Provides the operations defined for ClipStackSnapshot.

Source

pub fn empty() -> Self

Returns a snapshot containing no clipping constraints.

§Examples

use ailloli_ui_runtime::scene::ClipStackSnapshot;
assert!(ClipStackSnapshot::empty().is_empty());

Source

pub fn from_entries(entries: Vec<ClipEntry>) -> Self

Takes ownership of entries in their existing outer-to-inner order.

Empty, duplicate, and mutually disjoint shapes are accepted.

§Examples

use ailloli_ui_core::{ClipShape, Rect};
use ailloli_ui_runtime::scene::{ClipEntry, ClipStackSnapshot};
let entry = ClipEntry::new(ClipShape::Rect(Rect::new(0.0, 0.0, 10.0, 10.0)), false);
assert_eq!(ClipStackSnapshot::from_entries(vec![entry]).entries(), &[entry]);

Source

pub fn from_clip(clip: Option<ClipShape>, is_window_root: bool) -> Self

Builds an empty or single-entry snapshot from an optional shape.

is_window_root is ignored when clip is None.

§Examples

use ailloli_ui_runtime::scene::ClipStackSnapshot;
assert!(ClipStackSnapshot::from_clip(None, true).is_empty());

Source

pub fn entries(&self) -> &[ClipEntry]

Borrows entries in outer-to-inner order without allocating.

§Examples

use ailloli_ui_core::{ClipShape, Rect};
use ailloli_ui_runtime::scene::ClipStackSnapshot;
let snapshot = ClipStackSnapshot::from_clip(
    Some(ClipShape::Rect(Rect::new(0.0, 0.0, 5.0, 6.0))), false,
);
assert_eq!(snapshot.entries().len(), 1);

Source

pub fn is_empty(&self) -> bool

Returns true exactly when there are no clip entries.

§Examples

use ailloli_ui_runtime::scene::ClipStackSnapshot;
assert!(ClipStackSnapshot::default().is_empty());

Source

pub fn scissor_rect(&self) -> Option<Rect>

Returns the axis-aligned intersection of all clip bounding rectangles.

The result is used as a coarse GPU scissor; it does not preserve rounded corners. None means either no clip or an empty intersection, so callers needing to distinguish those cases must also inspect Self::is_empty.

§Examples

use ailloli_ui_core::{ClipShape, Rect};
use ailloli_ui_runtime::scene::{ClipEntry, ClipStackSnapshot};
let snapshot = ClipStackSnapshot::from_entries(vec![
    ClipEntry::new(ClipShape::Rect(Rect::new(0.0, 0.0, 10.0, 10.0)), false),
    ClipEntry::new(ClipShape::Rect(Rect::new(5.0, 2.0, 10.0, 4.0)), false),
]);
assert_eq!(snapshot.scissor_rect(), Some(Rect::new(5.0, 2.0, 5.0, 4.0)));

Source

pub fn single_shape(&self) -> Option<ClipShape>

Returns one representable clip shape for legacy callers.

Empty snapshots return None, one entry preserves its exact shape, and two or more rectangles collapse to their intersection. Any multi-entry stack containing a rounded rectangle returns None because flattening it would lose shape or root metadata.

§Examples

use ailloli_ui_core::{ClipShape, Rect};
use ailloli_ui_runtime::scene::ClipStackSnapshot;
let shape = ClipShape::RoundRect { rect: Rect::new(0.0, 0.0, 20.0, 10.0), radius: 3.0 };
assert_eq!(ClipStackSnapshot::from_clip(Some(shape), true).single_shape(), Some(shape));

Source

pub fn contains_point(&self, px: f32, py: f32) -> bool

Tests whether every clip shape contains a logical-pixel point.

An empty snapshot contains every point (vacuous intersection). Shape boundary and non-finite-coordinate behavior comes from [ClipShape].

§Examples

use ailloli_ui_core::{ClipShape, Rect};
use ailloli_ui_runtime::scene::ClipStackSnapshot;
let snapshot = ClipStackSnapshot::from_clip(
    Some(ClipShape::Rect(Rect::new(0.0, 0.0, 10.0, 10.0))), false,
);
assert!(snapshot.contains_point(4.0, 5.0));
assert!(!snapshot.contains_point(14.0, 5.0));