DiagramStudio.Core 0.1.0

DiagramStudio.Core

A dependency-light, UI-free engine for building, laying out, analysing, rendering and persisting node-link and swimlane diagrams in .NET — and for reading/writing Microsoft Visio .vsdx and GraphViz DOT files. Pure net8.0: no WPF, no commercial dependencies. Runs in an ASP.NET service, a console app, or a CI job just as happily as in a desktop app.

A drop-in WPF editor control built on this lives in DiagramStudio.Controls — but you don't need it. Core is genuinely useful on its own.

Use it standalone

• Generate Visio files from data, headless. Turn a database / JSON / domain model into a .vsdx your users open in Visio — from a web API, a CLI, or a nightly job. No Visio install, no WPF.
• Read .vsdx — pull shapes, connectors and Shape Data out of Visio files in C#.
• Render to PNG / SVG server-side — diagram thumbnails, report figures, embedded images.
• Convert between Visio .vsdx and GraphViz .dot.
• Lay out & analyse graphs programmatically — layered/tree/radial/force/circular/grid layouts; topological order, cycle detection, shortest path, connected components.

Install

dotnet add package DiagramStudio.Core

Example — data → Visio .vsdx, no UI

using DiagramStudio.Core.Model;
using DiagramStudio.Core.Layout;
using DiagramStudio.Core.Interop.Vsdx;

var doc = new DiagramDocument();
var a = doc.AddShape("Start", "startend");
var b = doc.AddShape("Review", "process");
var c = doc.AddShape("Approved?", "decision");
doc.AddLink(a.Id, b.Id);
doc.AddLink(b.Id, c.Id);
c.Data["owner"] = "Ops";                                  // travels as Visio Shape Data

LayoutCatalog.Create(LayoutCatalog.LayeredTb, new LayoutOptions()).Apply(doc);   // auto-layout

VisioBridge.Export(doc, "process.vsdx");                  // open this in Visio
var roundTrip = VisioBridge.Import("process.vsdx");        // …or read one back

What's in the box

• Document model — shapes, links, swimlanes, groups, and auto-resizing containers (DiagramDocument), with versioned JSON persistence.
• Rendering — a backend-neutral draw list (DiagramSceneBuilder) drawn by the shared Skia/SVG pipeline; arrowheads (both ends), dashes, bridges/line-jumps, rotation, image shapes.
• Routing — orthogonal, straight, and Bézier connectors, plus obstacle-avoiding orthogonal routing (A* over a Hanan grid).
• Layouts — layered (Sugiyama, via DotSharp), tree, radial-tree, force-directed, circular, grid, and lane-aware swimlane layout.
• Graph analysis — topological order, cycle detection, shortest path, connected components.
• Shape Data — arbitrary key→value metadata per shape, for data-aware diagrams.
• Interop — a GraphViz DOT bridge and a clean-room Visio .vsdx bridge (read & write shapes, connectors, kinds, colours, and shape data), built on the in-box System.IO.Packaging only.

License

MIT.