CHANGELOG.md

Changelog

The format is based on Keep a Changelog and this project adheres to Semantic Versioning.

[0.9.3] — 2026-02-16

• Fix: allow font formatting tokens to break text runs (#128)
• Fix: break text runs after horizontal tabs (\t) (#128)

[0.9.2] — 2026-02-03

• Fix: do not match chars which are not not by default presented as emojis as emojis (#125)

[0.9.1] — 2026-02-02

• Use ICU4X instead of Swash for text analysis (#119, #122)
• Support Emojis (#121, #122)

[0.9.0] — 2026-01-26

• Bump MSRV to 1.88 (#104)
• Bump fontique to 0.7.0 (#106, #107)
• Remove Range from pub API (#105)
• Remove fn TextDisplay::line_range (#105)
• Add fns {TextDisplay, Text}::{get_line, lines} (#105)
• Add fns Line::{text_range, top, bottom} (#105)
• Add parameter max_lines to fn measure_height (#105)
• Add fns FaceStore::{read_name, name_family, name_subfamily, name_full} (#110)
• Add struct LineIterator (#112)
• Support serde for FamilySelector and FontSelector (#113)
• Fixes for run-breaking and font selection (#104, #106, #107, #110)

[0.8.1] — 2025-09-17

• Fix sizing of empty lines by prefering to match some font than nothing (#102)

[0.8.0] — 2025-09-12

• Remove raster module (#91)
• Removed FontLibrary::init and Text::configure (#94)
• Remove support for harfbuzz_rs and fontdue (#95)
• Remove trait EditableText (#98)
• Replace fontdb with fontique, replacing usage of hard-coded font families and removing configuration of font aliases (#93, #94)
• Revise FontSelector type: make into a small Copy type and embed in Text objects. Replaces usage of pre-resolved FontId, allowing font selection to be delayed until run-breaking and to use inferred script. (#94)
• Replace field Effect::aux with Effect::e (#99)
• Support Swash in font library (#91) and use for text analysis (#94)
• Support font synthesis (#95)
• Add GlyphRun type, replacing fns Text{,Display}::glyphs{,_with_effects} with runs (#96, #99)
• Add fn TextDisplay::apply_offset (#98, #100)
• Fix behaviour of Align::Stretch in some cases (#100)

[0.7.0] — 2024-12-02

• Add Direction::AutoRtl, text_is_rtl (#80)
• Set the default font size to 16px (#80)
• Text API: do not expose prepare_runs, required_action (#81); more tweaks (#84)
• Move status tracking and Env fields into Text (#82)
• Remove TextApi, TextApiExt and EditableTextApi traits (#85)
• Revise fonts module: rename selector::Database to Resolver, separate out fontdb::Database, revise init (#87, #88)
• Bump MSRV to 1.80.0 (#87)

[0.6.0] — 2022-12-13

Stabilise support for Generic Associated Types (GATs). This requires Rust 1.65.0, removes the gat feature flag and affects the FormattableText trait. #75

Bump dependency versions: ttf-parser v0.17.1, rustybuzz v0.6.0 (#76), fontdb v0.10.0 (#77).

[0.5.0] — 2022-08-20

Error handling (#65):

• Add NotReady error type
• Most methods now return Result<T, NotReady> instead of panicking

Text environment (#68):

• Remove UpdateEnv type
• Rename Text::new to new_env, Text::new_multi to Text::new and remove Text::new_single. Note: in usage, the Environment::wrap flag is usually set anyway.
• Environment is now Copy
• Text::env returns Environment by copy not reference
• Text::env_mut replaced with Text::set_env, which sets required actions
• Environment::dir renamed to direction
• Enum Direction adjusted to include bidi and non-bidi modes.
• Environment::flags and its type EnvFlags removed. Environment::wrap: bool added and Direction adjusted (see above). PX_PALIGN option removed (behaviour is now always enabled).
• Parameters dpp and pt_size of Environment, TextDisplay::prepare_runs and FormattableText::font_tokens are replaced with the single dpem.

Text preparation:

• Add Action::VAlign requiring only TextDisplay::vertically_align action
• Remove TextDisplay::prepare (but TextApi::prepare remains)
• TextDisplay::resize_runs is no longer a public method
• TextDisplay::prepare_runs may call resize_runs automatically depending on preparation status
• Remove TextApi::resize_runs and TextApi::prepare_lines
• All TextApi and TextApiExt methods doing any preparation now do all required preparation, and avoid unnecessary steps.

Text measurements (#68):

• Add TextDisplay::bounding_box and TextApiExt::bounding_box (#68, #69)
• Add TextDisplay::measure_width and TextDisplay::vertically_align
• Add TextApi::measure_width and TextApi::measure_height
• Remove TextDisplay::line_is_ltr and TextApiExt::line_is_ltr
• Add TextApiExt::text_is_rtl
• TextDisplay::line_is_rtl and TextApiExt::line_is_rtl now return type Result<Option<bool>, NotReady>, returning Ok(None) if text is empty
• TextDisplay::prepare_lines returns the bottom-right corner of the bounding box around content instead of the size of content.

Font fallback:

• FontLibrary::face_for_char and face_for_char_or_first take an extra parameter: last_face_id: Option<FaceId>. This allows the font fallback mechanism to avoid switching the font unnecessarily. In usage, letters and numbers are selected as before while other characters are selected from the last font face used if possible, resulting in longer runs being passed to the shaper when using fallback fonts.

Misc:

• CI: test stable and check Clippy lints (#69).
• Add Range::is_empty
• Add num_glyphs feature flag (#69)
• Memory optimisations for TextDisplay: remove line_runs (#71)
• Replace highlight_lines with highlight_range (#72)
• Add fonts::any_loaded (#73)

Fixes:

• Do not add "line gap" before first line. (In practice this is often 0 anyway.)
• Do not vertically align text too tall for the input bounds.
• Markdown formatter: use heading level sizes as defined by CSS
• Fix position of text highlights on vertically aligned text (#67).
• Fix r_bound for trailing space (#71)

[0.4.2] — 2022-02-10

• Spellcheck documentation (#62)
• Fix selection of best font from a family (#63)

[0.4.1] — 2021-09-07

• Document loading order requirements (#59)
• Additional logging of loaded fonts (#59)

[0.4.0] — 2021-09-03

This is a minor release (mostly non-breaking). The primary motivation is to enable resvg to access the loaded font database. See PR #58:

• Breaking: update dependencies: bitflags = 1.3.1, fontdb = 0.6.0, harfbuzz_rs = 2.0, rustybuzz = 0.4.0
• Make fontdb::Database externally readable and set font families
• Additional control over loading fonts
• Performance improvements for alias lookups (trim and capitalise earlier)

[0.3.4] — 2021-07-28

• Fix sub-pixel positioning (#57)

[0.3.3] — 2021-07-19

• Document raster module and Markdown formatter (#56)
• Export DPU (#56)
• Default, Debug and PartialEq impls for some raster types (#56)

[0.3.2] — 2021-06-30

• Minor optimisations to SpriteDescriptor::new (#53)

[0.3.1] — 2021-06-17

• Make all families fall back to "sans-serif" fonts.
• Cache FontLibrary::face_for_char glyph lookups.

[0.3.0] — 2021-06-15

This release replaces all non-Rust dependencies allowing easier build/deployment (though HarfBuzz is kept as an optional dependency). There is also direct support for glyph rastering and some tweaks to improve raster quality making even very small font sizes quite legible.

• Add Effect::default method and default_aux param to glyphs_with_effects (#45)
• Replace font-kit dependency with the pure-Rust fontdb using custom font-family lists (#46), with support for run-time configuration (#48)
• Support font fallbacks (#47)
• Support rustybuzz for pure-Rust shaping (#47)
• Vertical pixel alignment (#49)
• Extend public API relating to fonts (#49)
• Add (glyph) raster module with Config struct and SpriteDescriptor cache key (#50)
• Use pixels-per-Em (dpem) for most glyph sizing, not pixels-per-font-unit (DPU) or height (#50)

[0.2.1] — 2021-03-31

• Add Option<Vec2> return value to TextDisplay::prepare and TextApi::prepare (#41)
• Fix missing run for empty text lines
• Fix justified text layout (#44)
• Explicitly avoid justifying last line of justified text (#44)
• Update smallvec to 0.6.1
• Update ttf-parser to 0.12.0

[0.2.0] — 2020-11-23

This release changes a very large part of the API. Both prepared and rich modules are removed/hidden; three new modules conv, fonts and format are added/exposed. Formatted text traits are added. The API around the main Text type changes massively.

Text type

• Export prepared::Text directly and hide the prepared module (#30)
• Split what was prepared::Text into TextDisplay (which excludes the text, environment and formatting data but includes positioned glyph information), and Text struct which wraps TextDisplay along with text and environment (#32)
• Add TextApi trait for run-time polymorphism over FormattableText texts (#32, #33)
• Add TextApiExt auto-implemented extension-trait (#33)
• Add EditableTextApi trait (#33)
• Replace prepared::Prepare with Action (#30, #33)
• Rename Text::positioned_glyphs → glyphs (#31)
• Add Text::glyphs_with_effects for glyph-drawing with underline/strikethrough (#31, #32)
• Make TextDisplay::prepare_runs and prepare_lines functions public (#33)
• Support indentation with tab character \t (#34)

Parsing and representation

• Add Markdown parser (#29 - #37)
• Add FontToken struct, FormattableText and EditableText traits with impls for &str, String and Markdown; these allow custom representations of formatted text (#32)
• Add FormattableTextDyn for run-time polymorphism (#33)
• Add FormattableText::effect_tokens for custom underlike/strikethrough effects (#34)

Fonts API

• All font API is moved into the public fonts module (#28)
• Add FontSelector and FontLibrary::load_font, load_pathbuf functions (#28)
• Adjust how loaded fonts are exposed; instead of an ab_glyph font we expose the font file data and font index (#30, #31)
• Adjust use of font-size units and add documentation (#31, #33)
• Switch dependency from ab_glyph to ttf-parser, but keep compatibility with ab_glyph (#31)
• Remove FontScale data type (unused; #30)

Miscellaneous

• Add type-conversion helpers conv::to_32 and to_usize (#31)
• Add Effect and EffectFlags types used for underline and strikethrough (#31)
• Add gat (Generic Associated Types) experimental feature (#33)
• Move Environment::bidi and wrap fields to new flags field; combine halign and valign to into align field (#33)
• Update xi-unicode dependency, allowing cleaner code (#34)

[0.1.5] — 2020-09-21

• Rewrite line-wrapping code, supporting must-not-wrap-at-end runs and resulting in much cleaner code (#24)
• Do not allow selection of the position after a space causing a line-wrap (#25)
• Fix alignment for wrapped RTL text with multiple spaces at wrap point (#26)

[0.1.4] — 2020-09-09

• Fixes for empty RTL lines (#21, #23)
• When wrapping text against paragraph's direction, do not force a line break (#22)

[0.1.3] — 2020-08-14

• Fix re-ordering of runs on a line (#18)

[0.1.2] — 2020-08-14

• Add embedding level to result of Text::text_glyph_pos (#17)
• Fix start offset for wrapped RTL text (#17)
• Fix Text::line_index_nearest for right-most position in line (#17)

[0.1.1] — 2020-08-13

• prepared::Text::positioned_glyphs now takes an FnMut closure and emits glyphs in logical order (#13)

[0.1.0] — 2020-08-11

Initial release version, comprising:

• basic font loading and font metrics
• Environment specifying font and layout properties
• rich::Text struct (mostly placeholder around a raw String)
• prepared::Text struct with state tracking required preparation steps

Text preparation includes:

• run-breaking with BIDI support
• glyph shaping via internal algorithm or via HarfBuzz
• line wrapping and alignment
• generating a vec of positioned glyphs
• cursor position lookup (index→coord and coord→index)
• generating highlighting rects for a range