Classic Ultima Online on Godot 4 .NET
GUO can draw the sea, rivers and lakes as moving water instead of the still tiles of the original client. It is off by default: Classic tiles draws the water exactly as ClassicUO does.
The water keeps the tiles’ own colours, so hued water, night and the seasons look as they did. On top of that a slow swell crosses it, crests catch the light, and surf breaks where the water meets the shore. Anything in the water moves it: a creature or a wading character sends out rings, a boat under way leaves a bow wave and a wake, and something that lands in the water splashes. It changes only how water is coloured: what is drawn, in which order, and what a click picks are the same as with Classic tiles.
ClassicUO’s own Animated water effect option still works with Classic tiles. A water style replaces it while the style is on.
Four more styles come as Store packs:
guo-water-pixel): chunky dithered water with whole-pixel
surf and glints, like a game from the early nineties.guo-water-cel): flat cartoon colour, bold bands of light,
white surf with a dark outline, ripples drawn as rings.guo-water-realistic): smooth light, deeper colour out
at sea, a sharp sun highlight with sparkles and soft surf. In the web build
it is a little plainer (no fine chop or sparkles), to keep it fast.guo-water-classicplus): the native water art and its fine dither,
with a quiet shimmer and small shore lap. It keeps the original colours
instead of adding white foam or broad highlights.Surf follows a continuous shore contour in all styles, with no surf below high cliffs.
Install one from the Store, select a deployment that contains it in the Store’s Configure deployment window, restart, then pick it under Options > Video > Water. A pack style is only numbers for one of the looks built into GUO: it carries no code. If its pack is removed, the water goes back to Classic tiles.
A setting a shard owner can use to choose which styles their players may use.
The decision behind all of it is ADR-0037 in docs/architecture/.
--water-style uo turns the style on for one run without saving it. The
scenario client.render.water visits the Britain docks and the Trinsic bay,
checks the draw list against ClassicUO’s, and takes stills. The perf probe has
britain-docks and trinsic-bay scenes for frame time with the style off and
on. For the pack styles, python tools/asset_store/water_packs.py --deploy DIR
installs all four and prints what to set for the scenario
client.render.water_pack, which is run once per style.
The pack scenario also checks a low sandy beach and holds the east docks
shore and bay cameras for motion review. Run it with --var style=classic for the native
comparison. The synthetic res://src/Render/Water/WaterShoreProbe.tscn
checks 48 synthetic coast cases: axis-aligned and diagonal shores in four
directions, mask windows at positive and negative world coordinates (including
ring-texture seams), falloff, dry-art overlaps, and the beach/cliff cutoff at
8/9 units above three water heights. It also checks Classic byte parity with
all five style models bound and verifies that setting the water bit reaches
the hue core’s debug branch. These checks use
rendered pixels; run it using godot-console --path godot/GUO
--rendering-method forward_plus res://src/Render/Water/WaterShoreProbe.tscn
and again with gl_compatibility. It needs a real renderer, without --headless.