Struct NullShaper 

pub struct NullShaper;

The shaper that shapes nothing.

Every run comes back empty, so text measures to a zero-sized box and no glyph is painted. A build with no text backend selected runs this, and a layout test that only cares about boxes can use it directly.

Trait Implementations

impl Clone for NullShaper

fn clone(&self) -> NullShaper

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for NullShaper

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

Formats the value using the given formatter.

impl Default for NullShaper

fn default() -> NullShaper

Returns the “default value” for a type.

impl TextShaper for NullShaper

fn shape( &mut self, _text: &str, _size_px: f32, _opts: ShapeOptions, ) -> Option<ShapedRun>

Shape text at size_px under the given ShapeOptions. Returns None when the input is empty, when no font can be resolved, or when shaping fails (rare).

fn measure( &mut self, text: &str, size_px: f32, max_width: Option<f32>, wrap: WrapMode, max_lines: Option<u32>, ) -> (f32, f32)

Measure a text run for layout. Returns the tight (width, height) in logical pixels of the shaped paragraph at size_px under the wrap / max_lines policy, clamped to max_width when Some.

fn measure_with_baseline( &mut self, text: &str, size_px: f32, opts: &ShapeOptions, ) -> (f32, f32, f32)

Same as Self::measure, plus the first-line alphabetic baseline offset from the top of the leaf box - the y at which Latin, Cyrillic, and Greek glyphs sit. FlexAlign::Baseline and the AccessKit text-position report consume it.

fn cache_len(&self) -> usize

Number of entries the backend currently holds in its shape cache. 0 for a backend that caches nothing.

fn set_capacity(&mut self, _entries: usize)

Resize the shape cache to the given entry count. The per-tick memory-budget sweep calls this when the cache outgrows lumen_core::components::MemoryBudget. No-op for a backend that caches nothing.

impl Copy for NullShaper