Scrivr

Because Scrivr renders off-DOM, it maps text dimensions manually via hardware-accelerated Canvas interactions wrapped in strict LRUCache architectures to guarantee 60fps throughput.

Constructor

new TextMeasurer({ lineHeightMultiplier?: number })

Accepts a multiplier variant (default 1.2) defining global vertical spacing limits mathematically calculated over maximum glyph heights natively.

Type Interfaces

`FontMetrics`

export interface FontMetrics {
  ascent: number;
  descent: number;
  lineHeight: number;
  xHeight: number;
}

`RunMetrics`

export interface RunMetrics {
  totalWidth: number;
  charPositions: number[];
}

API Methods

`measureWidth()`

measureWidth(text: string, font: string): number

Runs a hyper-cached simple measurement resolving the raw pixel width of an identical string and font matrix. (Uses Map<font, Map<text, width>>).

`getFontMetrics()`

getFontMetrics(font: string): FontMetrics

Retrieves fontBoundingBoxAscent/Descent ensuring a heavily stabilized string box. Rather than lines constantly bumping natively based on j, y, or p tails, the layout remains rigidly uniform across the entire document organically. Falls back to measuring "Hg" internally on unsupporting Chromium implementations.

`measureRun()`

measureRun(text: string, font: string): RunMetrics

Kerning check. Measures the string entirely via cumulative concatenation tracking accurately how the browser naturally merges specific characters tightly (AV). Because it calculates recursively, this resolves inside a bounded LRUCache<RunMetrics> limited safely to 2000 total keys aggressively.

`invalidate()`

invalidate(font?: string): void

Triggered manually following successful document.fonts.ready promises, throwing out prior cached font limits to force accurate Word-Wrap breakpoints to restart calculation cleanly.

Text Measurer