font

Fonts without a dependency: CSS font matching, the names design tools give to weights and styles, and reading a font file’s names, weight and style.

pick_closest is CSS Fonts Level 4 matching (§5.2) among the faces of one family, with variable faces that cover a weight range. weight_of_style, is_italic, split_postscript and same_family read the names fonts and design files carry ("Semi Bold Italic", "NeutrifPro-SemiBold"). read_font reads a TrueType, OpenType or WOFF file: family (typographic first), PostScript name, weight or wght range, style; font_count and read_font_at reach every font of a collection, and to_sfnt hands back the decompressed font file a shaper reads.

Install

Cargo feature font (enabled by default). To compile only this module:

cargo add helpers4 --no-default-features --features font

or in Cargo.toml:

[dependencies]
helpers4 = { version = "0.0.11", default-features = false, features = ["font"] }

Import path: helpers4::font.

Items

Item	What it does
font_count	How many fonts a font file holds: the number of fonts of a collection (.ttc), 1 for a TrueType, OpenType or WOFF file.
FontFace	A face of a font family, with the properties CSS font matching compares.
FontInfo	What a font file says about itself, as read_font reads it.
FontRequest	What a text asks of a family: the properties pick_closest matches.
FontStyle	The font-style of a face or a request.
is_italic	Whether a style name is italic or oblique, as design tools and font files write it ("Italic", "Semi Bold Italic", "Light Oblique").
pick_closest	Picks the face that CSS would use for a request, among the faces of one family: the CSS Fonts Level 4 matching algorithm (§5.2), as a pure function.
read_font	Reads what a font file says about itself: its family (typographic first), style, PostScript name, weight or wght range and whether it is italic.
read_font_at	Reads what the font number index of a file says about itself, as read_font does for the first one: the way to read the other fonts of a collection (.ttc), whose count font_count gives.
same_family	Whether two family names are the same family: compared without spaces or case, since design files and font files write "SF Pro", "SFPro" and "sf pro" for one family.
split_postscript	Splits a PostScript font name into family and style at its first hyphen: NeutrifPro-SemiBold is NeutrifPro and SemiBold.
to_sfnt	The font file as the sfnt that shapers and rasterizers read (skrifa, ttf-parser, …): a WOFF file is rebuilt with its tables decompressed; a TrueType, OpenType or collection file is already one and comes back as it is, without a copy.
weight_of_style	The CSS weight a style name stands for, as design tools and font files write it: Thin 100, ExtraLight 200, Light 300, Regular 400, Medium 500, SemiBold 600, Bold 700, ExtraBold 800, Black 900, ExtraBlack 950.

Error types

Documented on the page of the helper that returns them.

Type	Returned by
FontError	font_count, read_font, read_font_at, to_sfnt