Struct TextSystem 

pub struct TextSystem { /* private fields */ }

The shaping and rasterization state of one window. The font database it shapes against is not in here — that is the session’s (crate::session::Session), passed in as fs — because a font registered in one window has to shape in every window of the session. What is here is coupled to this window’s glyph atlas: the shaped-buffer cache stamps its positioned glyphs with the atlas stamp they were packed against, and the frame lists are what TextId indexes.

Implementations

impl TextSystem

pub fn new() -> TextSystem

pub fn budget(&self) -> usize

The byte budget the cache is evicted to; see Core::set_text_cache_budget.

pub fn set_budget(&mut self, bytes: usize)

Sets the budget. Takes effect at the next frame’s start, where eviction runs; nothing is evicted here.

pub fn bytes(&self) -> usize

The estimated bytes the cache holds (see ENTRY_BASE_BYTES).

pub fn len(&self) -> usize

How many shaped texts the cache holds (a long line’s chunks each count; the line itself does not).

pub fn long_lines(&self) -> usize

How many long lines are held.

pub fn is_empty(&self) -> bool

pub fn add( &mut self, content: &str, style: &TextStyle, res: &Resources, fs: &mut FontSystem, ) -> TextId

Registers a text for this frame, shaping (or reusing) its buffer.

pub fn measure( &mut self, content: &str, style: &TextStyle, res: &Resources, fs: &mut FontSystem, max_w: Option<f32>, ) -> TextMetrics

Measures content in style without adding a node: its unwrapped size, or with max_w (logical px) its size once wrapped to that width. The answer is what layout would give a text node with the same content and style at the current scale, wrap / max_lines / ellipsis included.

pub fn measure_rich( &mut self, spans: &[Span<'_>], base: &TextStyle, res: &Resources, fs: &mut FontSystem, max_w: Option<f32>, ) -> TextMetrics

measure for a rich-text paragraph.

pub fn add_rich( &mut self, spans: &[Span<'_>], base: &TextStyle, res: &Resources, fs: &mut FontSystem, ) -> TextId

Registers a rich-text paragraph for this frame. Spans shape as one flow, so wrapping crosses style boundaries correctly; past the long-line threshold the flow is chunked like a plain line’s.

Trait Implementations

impl Default for TextSystem

fn default() -> TextSystem

Returns the “default value” for a type.