Struct FontAtlas 

pub struct FontAtlas { /* private fields */ }

A texture atlas containing font glyphs for efficient WebGL text rendering.

FontAtlas manages a WebGL 2D texture array where each layer contains a single character glyph. This design enables efficient instanced rendering of text by allowing the GPU to select the appropriate character layer for each rendered cell.

Architecture

The atlas uses a WebGL 2D texture array where:

• Each layer contains one character glyph
• ASCII characters use their ASCII value as the layer index
• Non-ASCII characters are stored in a hash map for layer lookup
• All glyphs have uniform cell dimensions for consistent spacing

Implementations

impl FontAtlas

pub fn load_default(gl: &WebGl2RenderingContext) -> Result<Self, Error>

Loads the default embedded font atlas.

pub fn load( gl: &WebGl2RenderingContext, config: FontAtlasData, ) -> Result<Self, Error>

Creates a TextureAtlas from a grid of equal-sized cells

pub fn bind(&self, gl: &WebGl2RenderingContext, texture_unit: u32)

Binds the atlas texture to the specified texture unit

pub fn cell_size(&self) -> (i32, i32)

pub fn underline(&self) -> LineDecoration

Returns the underline configuration

pub fn strikethrough(&self) -> LineDecoration

Returns the strikethrough configuration

pub fn get_symbol(&self, glyph_id: u16) -> Option<Cow<'_, str>>

Returns the symbol for the given glyph ID, if it exists

pub fn get_base_glyph_id(&self, key: &str) -> Option<u16>

Returns the base glyph identifier for the given key

pub fn glyph_tracker(&self) -> &GlyphTracker

Returns a reference to the glyph tracker for accessing missing glyphs.

Trait Implementations

impl Debug for FontAtlas

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

Formats the value using the given formatter.