UORegionEditor

Visual region editor for custom UO maps.

Draw regions straight on the world map and export them as Sphere AREADEF/ROOMDEF, CentrED cedserver.xml, ServUO Regions.xml or ModernUO regions.json — the exclusive/inclusive edge conventions are handled for you.

Download

Two builds of the same app — take whichever suits you:

standalone	one exe, nothing to install
dotnet10	small download, needs the .NET 10 Desktop Runtime

Unzip and run UORegionEditor.exe. Point it at your shard's muls (File > Muls...), or connect to a region server and it downloads them for you. The map render is cached, so later starts are instant.

Build from source with dotnet build -c Release (.NET 10 SDK), or build-release.ps1 to produce both zips.

Tools

Select F1	drag boxes, resize with the handles, arrows nudge (Shift = 8), Del removes
Draw box F2	drag a rectangle, or click two opposite corners
Lasso F3 · Brush F4	freehand areas
Quick select F5	click takes the whole matching area — by colour or Tile type. Drag to limit the radius, Fill gaps to include clearings inside
4 corners F6	click corners, Enter finishes
F7–F10	the same four as erasers

Every tool follows the Z filter: lower Max Z to see inside a mountain and quick select takes the cave floor, not the roof above it. Don't overlap other regions makes the add tools stop at the edge of other visible regions. Add to selected region keeps adding boxes to one region instead of starting a new one each time.

WASD pans, the wheel zooms, Esc cancels — pressed again it clears the selection. Everything is undoable (Ctrl+Z / Ctrl+Y, or the History window).

Export

• Sphere .scp — right/bottom edges written exclusive (+1), as Sphere expects
• CentrED xml and Merge cedserver... — inclusive edges; merging replaces same-name regions and preserves the rest, with a timestamped .bak (stop the CentrED server first)
• ServUO Regions.xml — region class, priority and music
• ModernUO regions.json — same fields; edges written exclusive, as ModernUO expects
• Map image (PNG) — a shareable player map: every visible region as one silhouette in its own colour, with labels

Import reads all four back in, so moving a shard from one server to another is an import and an export.

Editing for picks the server your shard runs, and the region panel then asks only for that server's fields — Sphere events, flags and groups, or a region class, priority and music for ServUO/ModernUO. It sits in the connect dialog (saved per profile) and in Options for offline work, and marks its format in the Import/Export menus. Every format stays available whichever you pick.

Why it exists

Target	Right/bottom edge	The tool
Sphere RECT=x1,y1,x2,y2,0	exclusive	+1 on export, −1 on import
CentrED <Rect x1.. y2..>	inclusive	written as-is

Internally everything is inclusive tiles, so what you see highlighted is exactly what the region covers.

Region server

UORegionServer.exe shares one region list with your team. First run asks for the port, muls folder, map size (detected from the map file) and the owner account.

Startup prints one line — muls: 10 files, 1.2 GB - complete. check shows the detail:

  [x] map0LegacyMUL.uop         85 MB  terrain
  [ ] statics0.mul             MISSING  buildings, trees, roads
  [-] optional: artLegacyMUL.uop, MainMisc.uop, hues.mul, texmaps.mul, texidx.mul

Required: the map file, radarcol.mul, staidx0.mul, statics0.mul. Optional: tiledata.mul for Tile type mode, and the art files for the isometric view. The server hands them all to clients, so the whole team renders the same world.

Commands: adduser, passwd, setaccess, users, mapsize, check, logs, export. Regions persist to regions.json with .bak rotation, and every change also writes regions.scp, regions.centred.xml and regions.servuo.xml.

In the editor, Connect to server...: everyone sees each other's edits live and can jump to a teammate's view, and if the connection drops you keep working locally.

Selftest

UORegionEditor.exe --selftest report.txt runs ~100 headless checks — coordinate conversions, script round-trips, region maths, server sync and map rendering.

Credits

• ClassicUO — andreakarasho and contributors; its loaders read the art, tiledata and hues for the isometric view.
• CentrED# — Kaczy and contributors, and Andreas Schneider for the original CentrED, whose design informed a lot of this one.
• ServUO — Voxpire and the ServUO team, whose Data/Regions.xml format the ServUO export follows.
• Source-X — where the exact AREADEF parsing rules behind the exports were verified.
• False — testing and feedback.

Disclaimer

An unofficial fan-made tool, not affiliated with, endorsed by or sponsored by Electronic Arts Inc. or Broadsword Online Games. Ultima Online is a trademark of Electronic Arts Inc.

No Ultima Online client data is included here or in the releases — you supply your own muls.