Highly Performant & Scalable Ultima Online Server Emulator
https://www.modernuo.com
c-sharpcsharpcsharp-coredotnetdotnet-coreemulatorgplgplv3mmommo-enginemmorpgmmorpg-serveronlinerpgrunuoserverservuoultimaultima-onlineuo
a28a32f46d
## Summary
`Rectangle3DConverter.Write` corrupts a rectangle's Z range for certain bounds. The omit-z guard was:
```csharp
var writeZ = value.Start.Z is > sbyte.MinValue and < sbyte.MaxValue
|| value.End.Z is > sbyte.MinValue and < sbyte.MaxValue;
```
This drops `z1`/`z2` whenever **both** Z bounds sit at/outside the sbyte extremes — but `Read` reconstructs absent Z as exactly `z1 = -128, z2 = 127` (depth 255). So any rectangle that trips the omit condition without *being* that sentinel round-trips to depth 255 and is corrupted.
The concrete case: a **homeRange-style** bound `Start.Z = -128, End.Z = 128` (depth 256, the full vertical range used by spawners) gets `z1`/`z2` omitted on write, then reads back as depth **255** — silently losing the top z-level on every re-serialize.
(Spotted while working on #2505; spawners now prefer the `homeRange` form so most square bounds avoid this path, but any non-square `spawnBounds` or other `Rectangle3D` JSON is affected.)
## Fix
Omit Z only for the exact sentinel `Read` produces (`z1 == -128 && z2 == 127`); write it for anything else:
```csharp
var writeZ = value.Start.Z != sbyte.MinValue || value.End.Z != sbyte.MaxValue;
```
`Read` is unchanged, so existing `regions.json` rectangles that omit Z keep loading identically.
## Tests
New `Rectangle3DConverterTests`: round-trips the homeRange depth-256 case, the depth-255 sentinel, and ordinary/edge z values; asserts the sentinel omits Z while homeRange bounds write it. Server.Tests 717/717, UOContent.Tests 487/487.
|
||
|---|---|---|
| .config | ||
| .github | ||
| branding | ||
| dev-docs | ||
| Distribution/Data | ||
| Projects | ||
| .cursorrules | ||
| .editorconfig | ||
| .gitattributes | ||
| .gitignore | ||
| AGENTS.md | ||
| azure-pipelines.yml | ||
| CLAUDE.md | ||
| CODE_OF_CONDUCT.md | ||
| CONTRIBUTING.md | ||
| Directory.Build.props | ||
| FAQ.md | ||
| GEMINI.md | ||
| global.json | ||
| LICENSE | ||
| ModernUO.slnx | ||
| publish.cmd | ||
| publish.ps1 | ||
| publish.sh | ||
| README.md | ||
| rider-settings.zip | ||
| Rules.ruleset | ||
| SPONSORS.md | ||
| stylecop.json | ||
| THIRD-PARTY-NOTICES | ||
| version.json | ||
ModernUO 
Ultima Online Server Emulator for the modern era!
Requirements
Supported Operating Systems
Required Frameworks
All Operating Systems
Windows
Development
Supported IDEs
Getting Started
- Install prerequisite requirements
- Clone this repository (or download the latest):
git clone https://github.com/modernuo/ModernUO.git
- Open
ModernUO.slnto start developing
Building/Publishing
Interactive Mode (Recommended for new users)
Run ./publish.cmd (Windows) or ./publish.sh (Linux/macOS) with no arguments to launch the guided build tool. It will:
- Check prerequisites (.NET SDK, native libraries)
- Walk you through configuration and platform selection
- Build and publish the server to the
Distributiondirectory - Show deployment instructions for cross-compiled builds
Command Line
./publish.cmd [release|debug] [os] [arch]
os- Supported operating systemsarchx64- Intel/AMD 64-bitarm64- ARM 64-bit
Linux Prerequisites
Fedora, CentOS, RHEL, etc
dnf upgrade --refresh -y
# CentOS does not come with EPEL enabled
dnf install -y epel-release epel-next-release
dnf install -y findutils libicu libdeflate-devel zstd libargon2-devel liburing-devel
Ubuntu, Debian, etc
apt-get update -y
apt-get install -y libicu-dev libdeflate-dev zstd libargon2-dev liburing-dev
OSX Requirements
brew install icu4c libdeflate zstd argon2
Running the Server
- Follow the publish instructions
- The
Distributiondirectory is portable — copy it to your production server for deployment - Run
ModernUO.exeordotnet ModernUO.dllfrom theDistributiondirectory - On first run, the server will prompt you to configure game data file locations
Troubleshooting / FAQ
- See FAQ
Want to sponsor?
Thank you for supporting us! You can find out how by visiting the sponsors page.
Collaborators
Thanks
- RunUO Team & Community
- Voxpire, the ServUO Team & Community
- Karasho, Jaedan and the ClassicUO Community
Development Tools & Plugins provided with ♥ by
Code Signing Policy
Free code signing provided by SignPath.io, certificate by SignPath Foundation.
This program will not transfer any information to other networked systems unless specifically requested by the user or the person installing or operating it
Teams & Roles
Approvers & Committers: Development Team