Module fonts 

Fonts, font families and a font cache.

Before you can use a font in a PDF document, you have to load the FontData for it, either from a file (FontData::load) or from bytes (FontData::new). See the rusttype crate for the supported data formats. Use the from_files function to load a font family from a set of files following the default naming conventions.

The FontCache caches all loaded fonts. A Font is a reference to a cached font in the FontCache. A FontFamily is a collection of a regular, a bold, an italic and a bold italic font (raw data or cached).

Add fonts to a document’s font cache by calling Document::add_font_family. This method returns a reference to the cached data that you then can use with the Style struct to change the font family of an element.

There are two methods for using fonts in a PDF font: You can either embed the font data into the PDF file. Or you can use one of the three built-in font families (Builtin) that PDF viewers are expected to support. You can choose between the two methods when loading the font (from_files, FontData::load, FontData::new).

If you choose a built-in font family, you still have to provide the font data so that genpdfi has access to its glyph metrics. Note that it is sufficient to use a font that is metrically identical to the built-in font. For example, you can use the Liberation fonts instad of the proprietary Helvetica, Times and Courier fonts.

Built-in fonts can only be used with characters that are supported by the Windows-1252 encoding.

Note: The Font and FontFamily<Font> structs are only valid for the FontCache they have been created with. If you dont use the low-level render module directly, only use the Document::add_font_family method to add fonts!

Internals

There are two types of font data: A FontData instance stores information about the glyph metrics that is used to calculate the text size. It can be loaded at any time using the FontData::load and FontData::new methods. Once the PDF document is rendered, a printpdf::IndirectFontRef is used to draw text in the PDF document. Before a font can be used in a PDF document, it has to be embedded using the FontCache::load_pdf_fonts method.

If you use the high-level interface provided by Document to generate a PDF document, these steps are done automatically. You only have to manually populate the font cache if you use the low-level interface in the render module.

Structs

Font

A reference to a font cached by a FontCache.

FontCache

Stores font data that can be referenced by a Font or FontFamily.

FontData

The data for a font that is cached by a FontCache.

FontFallbackChain

A font fallback chain for handling mixed-script documents.

FontFamily

A collection of fonts with different styles.

GlyphCoverage

Statistics about glyph coverage for a given text.

Metrics

The metrics of a font at a given scale.

Enums

Builtin

A built-in font family.

FontStyle 🔒

RawFontData 🔒

Functions

from_file 🔒

from_files

Loads the font family at the given path with the given name.