@vyaz/core

Rich text layout engine — TypeScript, isomorphic (browser + Bun/Node.js), pixel-perfect typography.

The engine operates on a TextFrame → Paragraph → TextRun hierarchy, following W3C CSS Text and CSS Inline Layout.

Features

• Text frame layout — multi-paragraph frames with padding, wrapping, and vertical alignment
• Multi-font, multi-style text — bold, italic, size, colour, background, sub/superscript, letter-spacing, underline, strikethrough, text-transform
• Text alignment — left, center, right, justify, per paragraph
• Line wrapping — soft/hard breaks, white-space (normal nowrap pre pre-line pre-wrap)
• Lists — nested bullet / numbered, outside / inside markers, custom bullet char, roman / alpha
• Multi-column — balanced or auto fill
• Auto-fit — scale text proportionally to fit the container
• Shaping — opt-in { shaping: true } for GPOS kerning + GSUB ligatures (browser-metrics parity)
• Inline widgets — reserve width for embedded objects (type: 'inline-box') inside the text flow
• TextRun.data — open-ended metadata the layout engine ignores, for cross-cutting features like a hyperlink's href
• Tables — TableFrame grid layout alongside TextFrame: measured column widths/row heights, colSpan/rowSpan, per-side borders (dash patterns, rounded corners), before/after slots, nested tables — see the Tables guide
• Office-compatible mode — mode: 'office' for PowerPoint / DrawingML line boxes
• Font metrics — fontkit-based metric extraction; variable-font instancing; optional system font registry (Node)

Module Structure

src/
├── compile/        — DocumentCompiler, paragraph→token compilation
├── layout/         — Layout engines (Paragraph, TextFrame, Positioning, AutoFit)
├── measure/        — Font metrics, fontkit integration, system font registry
├── types/          — TypeScript type definitions (Document, Font, Layout)
└── utils/          — Helpers (font, list, text transform, env detection)

Generated API Reference

Full API documentation generated from source code — every class, interface, type alias and function, one page per symbol:

• Package index