use-typography

Composable primitive typography utilities for Rust.

use-typography is part of RustUse, alongside sibling repositories such as use-math, use-stats, use-optimization, use-simulation, use-control, use-signal, use-graph, use-materials, use-accessibility, use-color, use-text, use-time, and use-units. It groups small, focused crates for font sizing, line-height ratios, readable measure, modular scales, spacing systems, text block estimation, typographic unit conversion, and vertical rhythm helpers.

The RustUse approach in this workspace stays intentionally narrow:

• crates stay small and independently useful
• APIs stay explicit, documented, tested, and composable
• implementations favor practical f64, usize, String, &str, and small enums or structs
• dependencies stay minimal so each crate is easy to audit and adopt

These crates provide typographic calculation helpers, not a full layout engine. They do not depend on browser, DOM, font-rendering, or graphics libraries.

Workspace crates

• use-typography: thin facade crate that reexports the full typography workspace
• use-font-size: font-size and px/rem/em conversion helpers
• use-line-height: line-height ratio and readability helpers
• use-typography-measure: readable line-length helpers, exposed in code as use_measure
• use-modular-scale: modular typography scale helpers
• use-spacing-scale: spacing scale generation helpers
• use-text-block: text block line-count and height estimation helpers
• use-type-unit: px, rem, em, and pt conversion helpers
• use-type-rhythm: baseline grid and vertical rhythm helpers

Facade crate

If you want one dependency for the whole workspace, use use-typography. It reexports each focused crate and exposes the focused APIs directly so this works:

use use_typography::*;

let font = FontSize::new(18.0).unwrap();
let line_height = LineHeight::new(18.0, 27.0).unwrap();
let scale = modular_scale(18.0, ScaleRatio::MajorThird, -1, 1).unwrap();

assert!((font.rem(16.0).unwrap() - 1.125).abs() < 1.0e-12);
assert!((line_height.ratio() - 1.5).abs() < 1.0e-12);
assert_eq!(scale.len(), 3);

Status

This workspace is experimental while it remains below 0.3.0. Expect the public API to stay small and practical, but still evolve as the RustUse typography surface becomes clearer.

Development

Run the standard workspace checks from the repository root:

cargo fmt --all -- --check
cargo clippy --workspace --all-targets -- -D warnings
cargo test --workspace
cargo doc --workspace --no-deps