Struct FlexibleTextEngine 

pub struct FlexibleTextEngine {
    font_system: Arc<Mutex<FontSystem>>,
}

Cosmic-Text-backed layout engine.

Wraps a FontSystem (which loads system fonts on construction). Cosmic Text’s FontSystem is !Sync, so we wrap it in a Mutex so the engine can be shared across threads — necessary for caches (M-DYN.2-style) and the renderer’s &self access pattern.

Fields

font_system: Arc<Mutex<FontSystem>>

Implementations

impl FlexibleTextEngine

pub fn new() -> Self

Build the engine with a system-fonts FontSystem.

pub fn with_font_system(font_system: FontSystem) -> Self

Build the engine with a pre-existing FontSystem.

Useful for tests that want a deterministic font set, or for hosts that have already loaded a FontSystem for another purpose.

pub fn from_font_paths<P: AsRef<Path>>( paths: impl IntoIterator<Item = P>, ) -> Result<Self>

Build the engine with a FontSystem seeded from a list of font file paths. No system fonts are loaded — only the supplied files are available, and family-name lookups (WispText::with_font_family) resolve against this set.

Used by storybook exporters and tests that want byte-identical output across hosts (CI runners have different system fonts).

Errors

Returns io::Error if any path can’t be opened or isn’t a recognized font file.

pub fn from_font_bytes(bytes: impl IntoIterator<Item = Vec<u8>>) -> Self

Build the engine with a FontSystem seeded from raw font bytes. Useful for wasm32 targets (no FS access) and for crates that embed their bundled fonts via include_bytes! — see wisp_chart::chart_text for the canonical caller. No system fonts are loaded — only the supplied buffers are available, and family-name lookups (WispText::with_font_family) resolve against this set.

pub fn font_system_handle(&self) -> Arc<Mutex<FontSystem>>

Borrow the shared FontSystem handle. The FlexibleTextRenderer constructor uses this to wire layout + rasterization to the same font database (so glyph metrics agree).

pub fn layout_concrete(&self, text: &WispText) -> FlexibleTextLayout

Concrete-typed layout entrypoint — preserves the FlexibleTextLayout type so the renderer half can read the buffer without going through dyn downcasting.

Trait Implementations

impl Debug for FlexibleTextEngine

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

Formats the value using the given formatter.

impl Default for FlexibleTextEngine

fn default() -> Self

Returns the “default value” for a type.

impl WispTextEngine for FlexibleTextEngine

fn layout(&self, text: &WispText) -> Box<dyn WispTextLayout>

Lay out text. Backend returns a Box<dyn WispTextLayout> whose concrete type is recognized by the matching renderer.