PanoramicData.Render

A high-fidelity rendering engine for OpenXML (DOCX) documents, producing paginated SVG and PDF output.

What It Does

PanoramicData.Render is a virtual layout engine that reads .docx files and produces visually faithful SVG pages (one per document page) and PDF files. Unlike semantic converters that map document tags to HTML, this library calculates exact glyph positions, line breaks, and object anchors — acting as a layout engine comparable to a word processor's print path.

What It Is Not

• Not a DOCX editor. This is read-only, one-way conversion.
• Not an HTML converter. Output is SVG and PDF only; there is no HTML mapping.
• Not pixel-perfect. The goal is "visually indistinguishable at normal zoom." Sub-pixel identity with Microsoft Word is not claimed.
• Not a UI component. This is a library that produces files/strings. Visualization is the consumer's responsibility.

Quick Start

using PanoramicData.Render;

var options = new RenderOptions
{
    FontDirectories = ["/usr/share/fonts", "C:\\Windows\\Fonts"],
    FallbackFontFamily = "Liberation Sans",
    TargetDpi = 96
};

await using var stream = File.OpenRead("document.docx");
var renderer = new DocxRenderer(options);
var result = await renderer.RenderAsync(stream);

// Get SVG for each page
for (var i = 0; i < result.Pages.Count; i++)
{
    var svg = result.Pages[i].ToSvg();
    await File.WriteAllTextAsync($"page-{i + 1}.svg", svg);
}

// Or export as a single PDF
await using var pdfStream = File.Create("output.pdf");
await result.ToPdfAsync(pdfStream);

Key Design Decisions

Decision	Rationale
SkiaSharp for measurement & PDF	MIT-licensed, cross-platform, includes HarfBuzz for complex script shaping
Knuth-Plass line breaking	Produces paragraph-optimal line breaks matching Word's behaviour more closely than greedy algorithms
Twips as internal unit	Matches Word's internal precision (1/1440 inch), avoiding accumulated rounding errors
Full OOXML style cascade	Document Defaults → Theme → Numbering → Table → Paragraph hierarchy → Character hierarchy → Toggle properties → Direct Formatting

Supported Formats

Input	Output
.docx (OOXML)	SVG (one per page, fonts optionally embedded as WOFF2)
	PDF (single file via SkiaSharp PDF backend)

.doc (binary format) is not supported and never will be. Future versions may add .pptx and .xlsx support.

Requirements

• .NET 10.0+
• Access to .ttf and/or .otf font files used in the source document (system fonts, a directory, or embedded)

Documentation

• DESIGN.md — Architecture and technical design
• PLAN.md — Phased implementation roadmap
• docs/plans/ — Detailed per-phase deliverables

License

MIT — Copyright © 2026 Panoramic Data Limited

Contributing

See CONTRIBUTING.md for development setup and coding standards.