Class SymbolicTextAtlas

Index

Constructors

Properties

atlasSize baselinePx canvas glyphPx rowHeight

Methods

getOrAddGlyph getVersion layoutString

Constructors

constructor

new SymbolicTextAtlas(opts?: GlyphAtlasOptions): SymbolicTextAtlas
Parameters
- Optionalopts: GlyphAtlasOptions
Returns SymbolicTextAtlas

Properties

`Readonly`atlasSize

atlasSize: number

`Readonly`baselinePx

baselinePx: number

Distance from glyph top to baseline, constant for the chosen font size.

`Readonly`canvas

canvas: HTMLCanvasElement

`Readonly`glyphPx

glyphPx: number

`Readonly`rowHeight

rowHeight: number

Methods

getOrAddGlyph

getOrAddGlyph(char: string): GlyphInfo | null
Get or lazily rasterise a glyph. Returns null when the atlas is full — callers should fall back to a missing-glyph quad (typically the space character or a small box).
Parameters
- char: string
Returns GlyphInfo | null

getVersion

getVersion(): number

Bumps each time a new glyph is rasterised so the renderer knows to re-upload.

Returns number

layoutString

layoutString(s: string): { glyphs: GlyphLayoutEntry[]; totalAdvancePx: number }
Layout a UTF-16 string against the atlas. Code points outside the BMP are passed through as surrogate pairs which Canvas2D renders correctly. Empty advance entries are emitted for missing glyphs so the layout cursor still progresses.

out is filled with one record per code point. Returns the total advance width in atlas pixels (caller uses this for alignment).
Parameters
- s: string
Returns { glyphs: GlyphLayoutEntry[]; totalAdvancePx: number }