GodotUO

Classic Ultima Online on Godot 4 .NET

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Project maintained by DatMoshu Hosted on GitHub Pages — Theme by mattgraham

Feature Layers

Everything in GUO belongs to one of five layers. The layer decides what a change must prove before it is merged, whether it is on by default, and whether it ships in the game you download. The owner approved the layers on 2026-10-13; the binding text is the layer table in AGENTS.md and CONTRIBUTING.md.

Layer	What it holds	On by default?	In an exported game?
L0 Core port	ClassicUO’s own code, carried across	Yes	Yes
L1 Client options	GUO features a player switches on in Options	No	Yes, switched off
L2 Packs	Art, HD art, splats, screen effects, sounds, voices, zones, themes	Only what you install	Never bundled; installed from the Store
L3 Editor packages	The GodotUO editor: authoring, generation, AI, MCP, tours	Editor only	Never
L4 Labs	Experiments not ready to be an option	No, needs an opt-in build	Never

What each layer has to prove

• L0 is held to parity: it must behave exactly as ClassicUO does. Any deliberate difference carries a PORT DEVIATION (GUO) marker, and docs/upstream/GUO_DIVERGENCES.md lists them. See Parity and Drift.
• L1 options are off by default and need a profile field, an Options entry, proof that with the option off the game draws exactly as before, a scripted scenario and a section in docs/data_formats.md. Anything that changes how the world is drawn or how input works also needs an ADR. An option may not start another program, run Python or call a network service. Enhanced HD and Regional audio and recorded NPC voices are L1 options.
• L2 packs are typed content only: no code, and nothing runs when one is installed. See Content Packs.
• L3 editor code is compiled only into the editor (#if TOOLS), and every AI feature also sits behind the editor’s AI switch (Editor Settings > GUO > AI > Enabled). With it off, AI menus are hidden and no AI work runs; manual authoring always stays. See Editor.
• L4 Labs live in godot/GUO/src/Labs/<feature>/ and are compiled only into a Debug build made with -p:GuoLabs=true. Release and export builds leave them out even when the flag is set. Each Lab needs a README, a doctor launcher that says what to install, a scenario and a smoke line. The registry is empty today: no Lab ships yet.

Rules every change follows

1. A new chat command, profile field, Options entry, shader or edit to ported code starts with a short proposal or ADR that the owner decides. The first question: would ClassicUO ship it? If not, it belongs in a pack, the editor or Labs.
2. One feature per pull request, about 1,500 lines or 20 files at most unless agreed first.
3. Generating content belongs in the editor or Labs; the game only reads packs.
4. Anything that needs an outside program has a doctor launcher, and its failure text names that launcher.
5. Every L1 and L4 feature has a scenario under tools/scenarios/ and a line in the smoke.
6. Content that can be a pack goes to the Store.
7. Contributors and agents fill in the same review template: layer, toggle, parity proof, scenario, doctor and docs section.

Building with Labs

dotnet build godot\GUO\GUO.csproj -c Debug -p:GuoLabs=true

godot/GUO/src/Labs/README.md explains how a Lab registers its chat commands and Options rows.

See also

• Content Packs: what an L2 pack may carry
• Contributing: how to send a change
• Architecture: how the port is put together