# acdream

A modern open-source C# / .NET 10 Asheron's Call client.

Faithful port of the retail client's behaviour to Silk.NET with a modern,
plugin-friendly architecture. The code is modern; the behaviour is retail.

**Status:** playable pre-alpha. You can log in to an ACE server, walk and
run through Dereth, see other players animate correctly, watch the
day-night cycle, hear ambient audio, and take weapons out. Many systems
are still stubbed or in-progress — see roadmap.

## Stack

- **Language:** C# .NET 10
- **Graphics:** [Silk.NET](https://github.com/dotnet/Silk.NET) (OpenGL 4.3)
- **Audio:** OpenAL via Silk.NET
- **Dat parsing:** [Chorizite.DatReaderWriter](https://github.com/Chorizite/DatReaderWriter)
- **Networking:** Custom UDP + ISAAC cipher + game-message layer, wire-compatible
  with ACEmulator server

## What works

- Connecting to a local ACEmulator (ACE) server on `127.0.0.1:9000`
- Character selection and login
- Rendering Dereth terrain with retail-correct texture blending,
  per-vertex lighting, and road overlays
- Static scenery (buildings, trees, scenery objects) via EnvCell walker
- Animated characters (own + remote) with walk / run / strafe / jump /
  turn / attack motions sourced from the retail motion tables
- Network sync with remote players — you can watch other characters
  animate correctly, including speeds and directional motion
- Day-night cycle driven from the retail Region dat (0x13000000) —
  correct DayGroup picking via the retail LCG, correct keyframe
  interpolation, correct per-keyframe sky-object replace
- Weather (rain/snow particles synced from the server via the retail
  DayGroup name)
- Sky dome, stars, moon, clouds, sun — each rendered from the retail
  Region's SkyObjects with texture scrolling and alpha fade
- Plugin host with live event replay-on-subscribe

## What's stubbed or in-progress

- Indoor transitions (building interiors) — disabled, Phase B.3 pending
- Combat — animation works, damage math not wired
- Lightning visual — the retail PhysicsScript-driven flash is researched
  but not wired (see `docs/research/2026-04-23-lightning-real.md`)
- TimeSync drift — we only sync calendar on login, not periodically,
  so acdream's in-game clock gradually drifts from retail's
- Landscape draw distance — currently `ACDREAM_STREAM_RADIUS=2` (~400m)
  vs retail's several kilometres

See `docs/plans/2026-04-11-roadmap.md` for the ordered phase list.

## Building + running

**Requires:**
- .NET 10 SDK
- A retail Asheron's Call dat directory (Turbine/Microsoft property —
  supply your own). Contains `client_portal.dat`, `client_cell_1.dat`,
  `client_highres.dat`, `client_local_English.dat`.
- A running ACE (ACEmulator) server on `127.0.0.1:9000` (or override
  via env var)

**Launch (PowerShell on Windows — bash has trouble with the apostrophe
in "Asheron's Call"):**

```powershell
$env:ACDREAM_DAT_DIR   = "$env:USERPROFILE\Documents\Asheron's Call"
$env:ACDREAM_LIVE      = "1"
$env:ACDREAM_TEST_HOST = "127.0.0.1"
$env:ACDREAM_TEST_PORT = "9000"
$env:ACDREAM_TEST_USER = "testaccount"
$env:ACDREAM_TEST_PASS = "testpassword"
dotnet run --project src\AcDream.App\AcDream.App.csproj -c Debug
```

Offline CLI dat inspector (no server needed):

```
dotnet run --project src/AcDream.Cli -- "C:\path\to\Asheron's Call"
```

## Diagnostic env vars

| Variable | Effect |
|---|---|
| `ACDREAM_DUMP_SKY=1` | Per-second dump of the interpolated `SkyKeyframe` values + per-SkyObject draw info + texture alpha histograms |
| `ACDREAM_DUMP_MOTION=1` | Dump every inbound `UpdateMotion` + resulting `SetCycle` |
| `ACDREAM_STREAM_RADIUS=N` | Tune landblock visible-window radius (default 2 = 5×5) |
| `ACDREAM_NO_AUDIO=1` | Suppress OpenAL init |
| `ACDREAM_DAY_GROUP=N` | Force a specific DayGroup index for A/B-testing weather presets |
| `ACDREAM_RUN_SKILL=N` / `ACDREAM_JUMP_SKILL=N` | Client-side run/jump skill (default 200) |

## Layout

```
src/
  AcDream.App/                   rendering + audio + main loop (Silk.NET)
  AcDream.Core/                  game state, meshing, physics, sky, weather, lighting
  AcDream.Core.Net/              UDP + ISAAC + game-message layer
  AcDream.Cli/                   offline dat-inspector console app
  AcDream.Plugin.Abstractions/   plugin host interfaces
  AcDream.Plugins.Smoke/         example plugin

tests/
  AcDream.Core.Tests/            xUnit tests (742 passing)
  AcDream.Core.Net.Tests/        network-layer tests

tools/
  RetailTimeProbe/               Win32 P/Invoke ReadProcessMemory probe of
                                 the live retail acclient.exe — dumps
                                 TimeOfDay + sky-lighting globals so we
                                 can compare against acdream's state
  SkyObjectInspect/              dat-inspector for Region sky objects

references/                      vendored read-only reference code — ACE,
                                 ACViewer, WorldBuilder, holtburger,
                                 AC2D, Chorizite, DatReaderWriter.
                                 Gitignored.

docs/
  architecture/                  single-source-of-truth architecture doc
  plans/                         phase roadmaps + per-phase specs
  research/                      decompile-derived research, per-phase
                                 findings, deep-dive agent reports
  audit/                         phase-completion audits
```

## Development workflow

All AC-specific behaviour is ported from the decompiled retail client
(`docs/research/decompiled/`). The workflow is:

1. **Decompile first.** Find the matching function in the decompiled
   client.
2. **Cross-reference.** Check against ACE's C# port and ACViewer /
   WorldBuilder.
3. **Write pseudocode.** Translate C to readable pseudocode first.
4. **Port faithfully.** Translate line-by-line, preserving variable
   names and control flow.
5. **Conformance test.** Add tests using golden values from retail.
6. **Integrate surgically.** Minimise churn in the surrounding pipeline.

Guessing at AC-specific algorithms is explicitly forbidden — see
`CLAUDE.md` for the full workflow rationale and the list of failure
modes we've paid for in the past.

## Reference repos

We cross-reference five external projects for every retail behaviour:

- **ACE** (ACEmulator) — authoritative server-side protocol
- **ACViewer** — MonoGame dat viewer; good for character appearance
- **WorldBuilder** — Silk.NET dat editor; matches our stack
- **Chorizite.ACProtocol** — clean-room C# protocol library
- **holtburger** — most complete non-retail client; Rust TUI, full
  client-side behaviour
- **AC2D** — C++ AC-client emulator; has the real terrain split
  formula and 0xF61C movement packet format

See `CLAUDE.md` for which reference is authoritative for which domain.

## Licence

Not yet chosen. All external reference code is vendored under its own
licence; see `references/*/LICENSE`. The acdream source code itself is
unreleased — not yet distributed to the public. Once the licence
choice is made it will go in a top-level `LICENSE` file.

The AC dat files and the game's intellectual property remain the
property of Microsoft / Turbine. This project does not distribute any
of those files or assets — you must supply your own retail install.