Struct TextLayoutKey

pub struct TextLayoutKey { /* private fields */ }

Cache key for a text layout (content + style + quantized max width + wrap mode).

Text is represented by a DefaultHasher digest plus byte length. Uniform style keys include font and size but intentionally omit color and decoration. Styled keys add base/span colors after 8-bit quantization and still omit decoration. Widths are rounded to thousandths of a logical pixel. Therefore the key is optimized for cache reuse rather than being a lossless serialization of every request field.

Examples

use ailloli_ui_core::{Color, FontId, TextStyle};
use ailloli_ui_text::{TextLayoutKey, TextLayoutParams, WrapMode};
let style = TextStyle::new(FontId::Ui, 14, Color::WHITE);
let a = TextLayoutKey::from_params(&TextLayoutParams {
    text: "same", style, max_width: Some(80.0), wrap_mode: WrapMode::NoWrap,
});
let b = TextLayoutKey::from_params(&TextLayoutParams {
    text: "same", style, max_width: Some(800.0), wrap_mode: WrapMode::NoWrap,
});
assert_eq!(a, b);

Implementations

impl TextLayoutKey

pub fn from_params(params: &TextLayoutParams<'_>) -> Self

Builds a cache key from layout parameters.

NoWrap always uses the same sentinel width. Otherwise None uses u32::MAX; finite widths are lower-bounded at zero, multiplied by 1000, rounded, and saturating-cast to u32. NaN behaves as zero, while positive infinity and sufficiently large widths collide with the None sentinel. Uniform color and decoration do not affect this key.

Examples

use ailloli_ui_core::{Color, FontId, TextStyle};
use ailloli_ui_text::{TextLayoutKey, TextLayoutParams, WrapMode};
let white = TextStyle::new(FontId::Ui, 14, Color::WHITE);
let black = TextStyle::new(FontId::Ui, 14, Color::BLACK).underline();
let a = TextLayoutKey::from_params(&TextLayoutParams { text: "x", style: white, max_width: Some(10.0001), wrap_mode: WrapMode::Word });
let b = TextLayoutKey::from_params(&TextLayoutParams { text: "x", style: black, max_width: Some(10.0002), wrap_mode: WrapMode::Word });
assert_eq!(a, b);

pub fn from_styled_params(params: &StyledTextLayoutParams<'_>) -> Self

Builds a cache key from styled layout parameters.

The key includes ordered span ranges and base/span colors quantized to eight bits per channel. It omits all decorations. Unlike Self::from_params, a base color change normally changes the key; colors that quantize to identical RGBA8 values remain equivalent. Width normalization and sentinels are the same as for uniform text.

Examples

use ailloli_ui_core::{Color, FontId, TextStyle};
use ailloli_ui_text::{StyledTextLayoutParams, TextLayoutKey, WrapMode};
let white = TextStyle::new(FontId::Mono, 13, Color::WHITE);
let black = TextStyle::new(FontId::Mono, 13, Color::BLACK);
let a = TextLayoutKey::from_styled_params(&StyledTextLayoutParams { text: "x", base_style: white, spans: &[], max_width: None, wrap_mode: WrapMode::NoWrap });
let b = TextLayoutKey::from_styled_params(&StyledTextLayoutParams { text: "x", base_style: black, spans: &[], max_width: None, wrap_mode: WrapMode::NoWrap });
assert_ne!(a, b);

Trait Implementations

impl Clone for TextLayoutKey

fn clone(&self) -> TextLayoutKey

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for TextLayoutKey

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

Formats the value using the given formatter.

impl Hash for TextLayoutKey

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 for TextLayoutKey

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

impl Eq for TextLayoutKey

impl StructuralPartialEq for TextLayoutKey