Modern open-source C# .NET 10 Asheron's Call client. Faithful port of retail client behaviour to Silk.NET with a plugin API.
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Erik 3226c4bcab feat(net): message fragment header + fragment + assembler (Phase 4.3)
Ports the fragment layer of the AC UDP protocol. A UDP packet's body is
zero or more message fragments back-to-back; a logical GameMessage that
doesn't fit in ~448 bytes gets split across multiple fragments sharing
the same Id with differing Index values. The assembler handles
reassembly across arbitrary arrival ordering and duplicate fragments.

Added (all reimplemented from ACE's AGPL reference, see NOTICE.md):
  - Packets/MessageFragmentHeader.cs: 16-byte fragment header struct
    with Pack/Unpack, constants for MaxFragmentSize (464) and
    MaxFragmentDataSize (448). Bit-layout doc comment documents what
    each field is for.
  - Packets/MessageFragment.cs: readonly record struct bundling a
    header with its payload bytes; TryParse(source) parses one fragment
    from the start of a buffer and returns (fragment, consumed) for
    incremental parsing of multi-fragment packets. Refuses to parse
    fragments with impossible TotalSize (too small for header, too
    large for the 464-byte max, or larger than the source buffer).
  - Packets/FragmentAssembler.cs: buffers partial messages keyed by
    fragment Id. Ingest(frag, out queue) returns the assembled byte[]
    when the last fragment arrives, null while still waiting. Key
    correctness properties, all tested:
      * Single-fragment (Count=1) shortcut releases with no buffering
      * Out-of-order arrival (e.g. 2, 0, 1) releases on last arrival
        and assembles in INDEX order, not arrival order
      * Duplicate-fragment idempotence (re-sending same index is a no-op)
      * Missing fragments stay buffered; DropAll() forcibly clears them
      * Two independent messages can be assembled in parallel without
        interfering
      * messageQueue captured from first-arriving fragment (it's a
        property of the logical message, not individual fragments)

Tests (17 new, 37 total in net project, 114 across both test projects):
  - MessageFragmentHeader (4): pack/unpack round-trip, little-endian
    wire format, constants, size-check throw
  - MessageFragment (6): complete parse, insufficient header, oversized
    TotalSize, undersized TotalSize, incomplete body, two-back-to-back
    incremental parse
  - FragmentAssembler (7): single-fragment, in-order 3-fragment,
    out-of-order 3-fragment (tests index-order assembly), duplicate
    idempotence, missing-fragment buffered, two parallel messages,
    DropAll

Phase 4.4 (GameMessage reader + opcode handlers) next.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-04-11 14:20:53 +02:00
docs/plans docs(plan): Phase 3c terrain blending plan 2026-04-10 23:43:04 +02:00
src feat(net): message fragment header + fragment + assembler (Phase 4.3) 2026-04-11 14:20:53 +02:00
tests feat(net): message fragment header + fragment + assembler (Phase 4.3) 2026-04-11 14:20:53 +02:00
.gitignore chore: phase 0 — skeleton + dat asset inventory 2026-04-10 09:02:56 +02:00
AcDream.slnx feat(net): AcDream.Core.Net scaffold + ISAAC keystream (Phase 4.1) 2026-04-11 14:14:28 +02:00
CLAUDE.md docs(claude): project goal + lead-developer operating instructions 2026-04-11 13:39:21 +02:00
README.md chore: phase 0 — skeleton + dat asset inventory 2026-04-10 09:02:56 +02:00

acdream

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

Status: pre-alpha, not playable. Phase 0 only — dat file asset inventory.

Stack: .NET 10, Chorizite.DatReaderWriter for dat parsing. Silk.NET + Avalonia planned for rendering/UI (not yet wired up).

Requires: A retail Asheron's Call install (Turbine/Microsoft property — supply your own). Set ACDREAM_DAT_DIR environment variable to the directory containing client_portal.dat, client_cell_1.dat, client_highres.dat, and client_local_English.dat, or pass it as the first CLI argument.

Layout

  • src/AcDream.Cli/ — console app that dumps asset counts from a dat directory
  • references/ — local read-only reference material (ACE, ACViewer, WorldBuilder, DatReaderWriter, holtburger, retail AC install). Gitignored.

Run

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

Or set ACDREAM_DAT_DIR and run without args.