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eafc6208d9
read_face (crates/text/src/sfnt.rs) also listed faces with none of the tables skrifa reads glyph outlines from (glyf, CFF, CFF2, VARC), such as faces whose glyphs are bitmaps only or whose outlines are in Apple's hvgl table. The renderer draws glyphs only from those outlines, so text set in such a face is blank. On macOS 27.0.1 the system scan listed "GB18030 Bitmap" (NISC18030.ttf, bdat bitmaps), so it appeared in the Font menus. read_face now returns no face when the table directory has none of these tables, before it reads the name table. In a collection, the faces with outlines keep their index. VectorCraft's font scan has the same check (storytold/vectorcraft#781).
filmcraft-text
FilmCraft's text engine (layer L1: depends on filmcraft-color, skrifa, harfrust,
unicode-bidi and unicode-linebreak). It draws graphic-clip text and shapes, caption burn-in
and the Timecode / Clip Name effects. Pure Rust; it builds for wasm32-unknown-unknown.
| Module | What |
|---|---|
fonts |
Font database. Bundled faces (always present, also on the web): Inter Regular / Medium / SemiBold / Bold / Italic, JetBrains Mono Regular, Noto Serif Regular — all SIL OFL 1.1, unmodified, in assets/fonts/ with .attribution sidecars. More faces come from FontSources: DirectorySource::system() scans the platform font folders on first need (only the name and OS/2 tables are read, via sfnt); on wasm the scan finds nothing and hosts can call add_font_data. resolve(family, style) picks a face, synthesises bold/italic when the family lacks them, and falls back to Inter (flagged missing). fallback_for finds a face for characters the chosen face lacks: bundled faces first, then the optional craft-fonts faces (CRAFT_FONTS, embedded by build.rs when built with CRAFT_FONTS_DIR; Mincho for serif text, Gothic otherwise, nearest weight), then loaded system faces. |
layout |
Paragraph layout: per-character font fallback → bidi levels (UAX #9) → items (runs of one face, direction and size) shaped with harfrust (OpenType kerning, ligatures, marks, complex scripts) → tracking → line breaking at UAX #14 opportunities (area text) → visual reordering per line → alignment (left / centre / right / justify), leading (added to the natural line height), baseline shift, all caps / synthesised small caps (78 %), underline. Every character boundary gets a caret stop (ligatures are split evenly), so editors can place carets, hit-test and draw selections. Layouts are cached by text + style (512 entries, LRU). |
layout_rich |
Per-character style runs (StyleRun: a byte range with its own TextStyle): runs split shaping items (font, size, tracking, caps, faux styles), baseline shift and underline apply per run, a line holding a larger run is pushed down from the line above (baseline distance = max(base line height, previous descent + this line's ascent + leading)), and every glyph / underline carries its style index so renderers can colour runs (render::draw_run). |
raster |
Our anti-aliased rasteriser (non-zero winding, 5 sub-scanlines, exact horizontal coverage, active-edge list), contour paths with transforms, rounded rectangles, ellipses, polygons and outline emboldening. Coverage is linear, so compositing in linear light is correct. |
render |
Glyph outlines (cached per face + glyph) and glyph masks (cached per size in ⅛ px, ¼-px horizontal phase, synthetic style). Axis-aligned uniform transforms use the mask cache with sub-pixel x positioning; rotated / skewed / non-uniform transforms fill the transformed outlines of the whole run in one pass. Synthetic bold grows outlines by 2.5 % of the size; synthetic italic slants by 12°. |
mask |
Outer / centre / inner strokes from an exact Euclidean distance transform (Felzenszwalb–Huttenlocher) with sub-pixel refinement, a three-pass box blur (≈ Gaussian) for shadows, offsets. |
Coordinates
Pixels, y down. Point text: the origin is the alignment point on the first baseline (left edge,
centre or right edge). Area text (ParagraphStyle::width): the origin is the box's top-left.
Performance
A three-line, centred, 96 px bold title at 1080p (perf::three_line_title_is_fast), release build
on an M-series Mac: about 1.6 ms cold (shaping, outline extraction, glyph rasterisation) and
0.15 ms warm (layout cache + glyph cache). The test fails if the warm path exceeds 40 ms.
Not yet
OpenType feature toggles beyond kerning/ligatures, variable-font axes, hinting, colour (emoji) glyphs, and hyphenation. Words longer than an area-text line overflow instead of breaking mid-word.