Struct FontLibrary 

pub struct FontLibrary { /* private fields */ }

A copy-on-write font database. Construction never discovers system fonts. Registered source bytes are retained; cloned libraries share snapshots.

Implementations

impl FontLibrary

pub fn new() -> Self

Creates an empty library with no filesystem access or discovery.

pub fn load_file( &mut self, path: impl AsRef<Path>, ) -> Result<Vec<FontIdentifier>>

Loads one explicit font file into immutable memory, never a lazy file source.

pub fn load_data(&mut self, data: Arc<[u8]>) -> Result<Vec<FontIdentifier>>

Registers bounded in-memory OpenType/TrueType data atomically, including collections and color fonts. At most 4096 faces / 256 MiB are admitted.

pub fn load_dir(&mut self, directory: impl AsRef<Path>) -> Result<usize>

Loads a sorted project directory tree atomically; symlink directories are not followed. At most 4096 entries are visited, independent of face count.

pub fn load_system_fonts(&mut self) -> Result<usize>

Explicitly indexes installed font metadata without retaining every file. Font discovery still performs I/O; bytes are loaded on first use.

pub fn load_system_family(&mut self, family: &str) -> Result<usize>

Explicitly discovers installed fonts, indexing only the requested family.

pub fn default_family(self, family: impl Into<String>) -> Self

Sets generic family aliases in a new snapshot, without font discovery.

pub fn database(&self) -> &Database

Borrows the frozen parser database for SVG/formula import adapters. Mutation still requires a new FontLibrary snapshot.

pub fn snapshot_id(&self) -> u64

Identity of this immutable environment for resource/layout cache keys.

pub fn len(&self) -> usize

Registered face count, including collection faces.

pub fn is_empty(&self) -> bool

Whether no fonts have been registered.

pub fn retained_bytes(&self) -> usize

Logical retained source bytes, excluding parser and platform overhead.

pub fn used_fonts(&self) -> Vec<FontIdentity>

Actual selected faces and non-cryptographic source hashes, in stable order.

Trait Implementations

impl Clone for FontLibrary

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for FontLibrary

fn fmt(&self, formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for FontLibrary

fn default() -> Self

Returns the “default value” for a type.

impl From<&FontLibrary> for FontEnvironment

fn from(fonts: &FontLibrary) -> Self

Converts to this type from the input type.

impl From<FontLibrary> for FontEnvironment

fn from(fonts: FontLibrary) -> Self

Converts to this type from the input type.

impl RefUnwindSafe for FontLibrary

impl UnwindSafe for FontLibrary