Reduces the world-save freeze window from ~740ms to ~78ms (measured on a synthetic 10M-entity / 1.7GB world, 24 cores, through the real pipeline classes) by removing the per-entity handoff between the game loop and the serialization workers, fixing how large indivisible payloads are scheduled, rewriting the BufferWriter hot path, removing per-entity placement state entirely, and finally replacing the global serialized-types tracking with a per-file type table (idx v4) that also shrinks idx files by ~21% and speeds the background write phase. The pipeline has also been validated end-to-end on live-copy worlds in the multi-million-entity range, where the freeze is drain-bound (real `Serialize()` costs far more CPU per byte than synthetic writes) — the same structural wins hold, and entity/file round-trips are byte-clean across both load paths.
## The problem
The freeze window is `max(main-thread handoff, slowest worker drain)`:
1. **The producer was the bottleneck.** The main thread round-robined every entity through per-worker `ConcurrentQueue`s — two interlocked ops per entity, ~740ms of freeze floor at 10M entities before any serialization happened.
2. **Round-robin distributes count, not cost.** "Deep" systems (50MB generic persistence blobs) and "thick" entities (100K-item storage keys) landed on arbitrary workers, producing lopsided drain times on large worlds.
3. **Worst-case scheduling.** `GenericEntityPersistence.Serialize` pushed its self-payload *after* all entities, and generic persistences sort last in the registry — so the biggest indivisible blobs started serializing at the very end, extending the freeze by their entire duration.
## The fix
**Commit 1 — chunked handoff + LPT scheduling + heap pre-sizing:**
- Pooled 4096-entity chunks published to one shared queue; workers pull chunks and load-balance dynamically (a worker busy with a thick entity simply takes fewer chunks).
- `Persistence.SerializeAll` pushes systems largest-first (LPT) using the previous save's payload size (or loaded file size on first boot); self-payloads get dedicated single-entity chunks so they overlap the entity stream instead of ending it.
- Worker heaps pre-size from the loaded save's `.bin` totals, eliminating copy-on-grow inside the first save's freeze.
- `SpinWait` backoff in the drain loop (never `Sleep(1)`), per-worker balance stats logged in debug builds (the call site is compiled out of Release), 1MB snapshot write buffer.
**Commit 2 — workers iterate the dictionaries directly + main thread joins the drain:**
- `GenericEntityPersistence` publishes 4096-slot ranges over its dictionary's backing entries array; workers serialize occupied slots (`value != null`) directly through a `ShadowEntry<TValue>` struct mirroring the runtime's private `Entry` layout. Safe because the dictionary is frozen during `Saving` (mutations divert to the pending safety queues).
- The layout is **proven at startup before any code reads through it**: validation measures the true `Entry` stride via precise allocation accounting (guaranteeing all shadow reads are in-bounds), then verifies every key/value of a churned, resized, freelist-exercised dictionary — reading value slots as raw pointer bits only, never materializing a managed reference until the layout is proven. If a future runtime changes `Dictionary` internals, validation fails with a logged warning and saves fall back to the (fully maintained) enumerate-and-push path.
- The main thread joins the drain via an inline worker after publishing, instead of idling — worth a full worker share, proportionally more on low-core hosts.
**Commit 3 — 2.2x faster BufferWriter write path, single-pass short strings:**
- PGO already devirtualizes and inlines every `IGenericWriter.Write` callsite (interface vs concrete measured identical) — the real per-write cost was the non-inlinable `Index` setter (range-check throw path + per-write high-water tracking) plus span bounds checks. Writes now reserve capacity once, then do an unaligned store through a ref with a raw index increment; the high-water mark folds at Seek/Resize instead of per write.
- Class-level implementations of the hottest default interface methods keep nested writes inlined (a DIM re-dispatches on `this` even at a devirtualized callsite).
- Strings of 85 chars or fewer encode once into a stack scratch instead of walking the string twice (`GetByteCount` + `GetBytes`). Byte output is identical.
- Measured: 34.4 → 15.7 ns/entity on a generated-style write mix; end-to-end freeze ~99ms → ~74-82ms.
**Commit 4 — branch-free fallback push loop:**
- A bare `foreach { PushToCache(entity); }` runs at 2.3ns/entity; the same loop carrying a per-entity heavy-check runs 2.3x slower — the cost is the fatter loop body defeating tight-loop codegen. Entity-level >1MB payloads are rare enough to ride in shared chunks; system self-payloads (the large ones) are still explicitly scheduled largest-first.
**Commit 5 — drop the 9-byte per-entity placement state; snapshots write from worker segment logs:**
- Every `ISerializable` carried `SerializedThread/SerializedPosition/SerializedLength` so `WriteSnapshot` could gather each entity's bytes from the worker heaps in dictionary order. But the idx records absolute positions — bin order is free — so the snapshot is now written in worker-heap order and the join inverts: workers log segments (owner, slot range, heap start) plus one length per record as they serialize; positions are implicit because a worker's writes are contiguous, and identity comes from re-walking the same snapshot slots in the same order (stable until `PostWorldSave`).
- Chunks are persistence-homogeneous (the partial chunk publishes at each `SerializeAll` boundary) so segments route to files by owner with zero per-entity state. Self-payloads keep placement as three private fields on the handful of persistence instances.
- Net: 9 bytes (plus padding) of resident state removed from every item, mobile, guild, and account on every shard; three interface-property stores per entity leave the drain hot path (stamping dirtied one cache line per entity mid-freeze — the lengths log is one sequential stream); each segment's bytes hit the bin as a single span write instead of one copy per entity, speeding the background write phase; and `IGenericSerializable` shrinks to just `Serialize(IGenericWriter)`. Transient cost: ~4 bytes per entity in pooled per-worker logs, released after each write. The save format was unchanged at this point (idx v3, same loader); the v4 bump comes later in the branch.
**Commit 6 — staged file writes replace memory-mapped snapshot writing:**
- `MemoryMapFileWriter` is removed. `FileBufferWriter` composes through the full `BufferWriter` raw write path into a pooled staging block that drains to the file as large sequential positional writes (`RandomAccess.Write`); seeks flush the block and move the file offset, so backwards patches (the idx entity count) become small positional writes.
- Memory-mapped composition paid a soft page fault on every composed page plus unpredictable dirty-section teardown stalls at dispose — measured ~4x slower end-to-end than staged writes at snapshot sizes.
**Commits 7–11 — idx v4: per-file type table replaces SerializedTypes.db and all runtime type tracking:**
- Previously every `Write(Type)` from every worker enqueued into a shared `ConcurrentQueue<Type>` during the freeze (interlocked writes on a shared cache line, millions of mostly-duplicate entries), the background phase drained and deduped it all into a `HashSet`, and the snapshot recomputed `xxHash64(Type.FullName)` once per entity record (~5.4M redundant hashes per save on a large world) to write 9-byte tag+hash idx records plus a global `SerializedTypes.db`.
- The db's only real job was diagnostics: the string name behind "Type `<X>` was not found. Delete all of those types?" during idx loading. That map now lives in the idx itself: each `GenericEntityPersistence<T>` keeps an insertion-ordered `Type -> ushort` table, hydrated at `AddEntity` and on every deserialize path — one dictionary `TryAdd` per entity add on the game thread, amortized across gameplay, and provably immutable while the background writer reads it (adds divert to the pending queues during saves).
- idx v4 layout: the table (names only) is written before the records; records reference it by 2-byte index, shrinking from 33 to 26 bytes (−21%). The loader resolves each table name **once** (`FindTypeByHash(ComputeHash64(name))` — semantically identical to v3 resolution, `TypeAlias` included) into a constructor array, and each record becomes an array index instead of an 8-byte hash read plus dictionary probe. The unresolved-type prompt now surfaces once per type, with the name.
- Deleted outright: `World.SerializedTypes`, the drain/dedupe pass in `WriteFiles`, `BufferWriter`'s type tracking (its `Write(Type)` is now pure — payload format unchanged: tag byte + xxHash64), `FileBufferWriter`'s typeSet parameter, `Persistence.WriteSerializedTypesSnapshot`, and the adhoc db write. SerializedTypes.db is no longer produced.
- **Backward compatibility:** v0–v3 saves (including their SerializedTypes.db and legacy tdb files) load exactly as before, and every legacy load path hydrates the new table so the first v4 save after an upgrade is complete. Stale db files in existing save folders are simply ignored. Verified live: a v3 save boots, saves as v4 (Items.idx −20.2% on a dev world), and reloads with identical entity counts.
## Measured (synthetic 10M entities / 1.7GB, 64+64+32MB system blobs, 24x 2MB thick entities, dense write profile, 24 cores)
| Metric | Before | After |
|---|---|---|
| Steady-state freeze | ~740 ms | **~78 ms** |
| Main-thread publish cost | ~740 ms | **~0.1 ms** |
| Steady-state allocations | 0 | 0 (by iter 2) |
| Worker byte-load spread | 2x | ~1.15x |
The freeze is now bound by pure serialize throughput (payload / cores).
## Tests
- 779 Server.Tests + 501 UOContent.Tests pass.
- New across the branch: chunk fill/flush/owner-boundary tests, pool reuse/clear tests, an end-to-end multi-worker drain through the real wake/push/flush/pause protocol, a 50K-entry churn equivalence test for the shadow iteration re-walk (the exact pairing the snapshot writer relies on), byte-level BufferWriter output/position pins, `RuntimeLayoutIsSupported` so a silent fallback on a future runtime upgrade fails loudly in CI, and a full snapshot **round-trip test** that serializes 25K entities plus a self-payload through real workers, writes the idx/bin from the segment logs, and reloads them through the standard loader (now in v4 format).
- For idx v4 specifically: `FileBufferWriter` staging/drain/seek-patch and oversized-item tests, type-table registration tests, a hand-written v4 fixture proving an unresolvable type name skips only its own records through the console confirmation flow, and a hand-written **legacy v3 fixture** proving old saves still load and hydrate the type table for their next save.
## Trade-offs
- Chunk scheduling is nondeterministic, so worker heaps ratchet to each worker's max-ever draw rather than a fixed share. With slot ranges the balance is tight (~1.15x), so the effect is small; a shared slab pool remains an option if production shows retention creep.
- Entity-level heavy items inside slot ranges are serialized wherever they're encountered (no LPT for them); worst-case tail is one thick entity's serialize time (~ms). System self-payloads — the large ones — are still explicitly scheduled largest-first.
- Snapshot-write error granularity is per segment rather than per entity (heap-bounds bugs were the only thing the per-entity catch ever caught; idx metadata reads keep per-record granularity).
- idx v4 is a save-format version bump: old saves load unchanged through the preserved legacy paths, but saves written by this branch require this loader. Per-persistence type tables cap at 65,535 distinct entity types per boot (hard throw, orders of magnitude of headroom), and a type's table slot persists until restart even if its last entity is deleted — a few stale name entries per file, by design.
## Problem
On headless Linux deployments (systemd service, Docker without a TTY, `nohup`), the ModernUO process pegs a full CPU core even when idle. It does not reproduce on Windows because that runs with an interactive console.
## Root cause
`ConsoleInputHandler` runs a background thread (named "Console Input Handler") that loops on `Console.ReadLine()`. When stdin is **not** an interactive terminal, `Console.ReadLine()` returns `null` at end-of-stream **immediately** on every call, so the loop `continue`s in a tight spin — one core at 100%.
Reproduced in a container running the actual distribution: the "Console Input Handler" thread sat at ~90% CPU on a headless boot; with a blocking stdin it dropped to idle.
## Fix
1. **Detect headless once at startup:** `Core.Headless = Console.IsInputRedirected`.
2. **Extract a testable `ConsoleInputPump`** that owns the input stream: per line read, it *atomically* (under one lock) either delivers the line to a waiting prompt or dispatches a console command, and it **ends on EOF instead of spinning**. Cleanup runs unconditionally in a `finally`, so a pending prompt is always released (never hangs). Replaces the old `async void` loop and the fragile `_expectUserInput` / two-`AutoResetEvent` / `_input` handshake.
3. **`ConsoleInputHandler` becomes a thin headless-aware facade** over the pump. Headless: the reader thread never starts (`Console input disabled (headless: stdin is not a TTY).`), and `ReadLine()` throws a fatal `HeadlessConsoleInputException`.
4. **Data-gating and first-boot prompts** (deserialization "delete bad types? y/n", save-conflict, config/expansion setup) now route through `ConsoleInputHandler.ReadLine()`, so a headless server crashes fatal with a clear message instead of reading `null` (previously an NRE or a silent wrong branch).
Design decision (model b): headless servers are expected to be supplied with configuration/save data (including the owner account); interactive prompts when headless are fatal by design.
## Testing
- New `ConsoleInputPumpTests` (5 tests): EOF ends the loop without spinning; command dispatch; a pending prompt receives the next line; EOF while a prompt is pending completes it with `null` (no hang); a throwing command lookup does not hang a pending prompt. The tests synchronize on real pump state (no `Thread.Sleep`), so they are deterministic on slow CI.
- Full `Server.Tests`: no new failures introduced.
## End-to-end verification (Docker, real distribution)
| | Console Input Handler thread | Container CPU |
|---|---|---|
| Before fix (headless boot) | ~90% | ~199% (2 cores) |
| After fix (headless boot) | **not started** | **~11%** |
After the fix, a headless boot logs `Console input disabled (headless: stdin is not a TTY).`, loads the world normally, and idles instead of spinning.
## Problem
Items dropped on the ground never decay. Corpses do, which makes the breakage look selective — but corpses are unaffected only because `Corpse.BeginDecay` runs its own `InternalTimer` and never touches `DecayScheduler`. Ordinary items are the only things that depend on the scheduler.
## Root cause
`Item.MoveToWorld` called `SetLastMoved()` — which triggers `UpdateDecayRegistration()` — at the *top* of the method, before detaching the item from its parent and before assigning the new map. `CanDecay()` reads `Decays`, `Parent`, **and** `Map`, so registration was evaluated against the item's *pre-move* state.
Because the `Item` constructor sets `m_Map = Map.Internal`, and `Mobile.Lift` calls `item.Internalize()` to put an item on the cursor, registration was consistently one step behind:
| State | Tracked for decay? | |
|---|---|---|
| Item on the ground | **No** | never decays |
| Item held on the cursor | **Yes** | backwards |
Nothing corrected it afterwards: the later `m_Map = map` assigns the field directly, bypassing the `Map` property setter, and that setter does not refresh registration either. With no parent, `RemoveItem` (which *does* re-register) never runs.
World load masked this — `ItemPersistence.PostDeserialize` re-registers every item against its final state, so decay appears to work for items that survive a restart. Only freshly dropped items are affected.
**Fix:** stamp `LastMoved` up front so decay math stays correct, then call `UpdateDecayRegistration()` once the parent, map, and location are final.
## Audit of the rest of the call sites
All 16 `SetLastMoved()` call sites were reviewed. `SetLastMoved()` must keep refreshing registration — `LastMoved` feeds `ScheduledDecayTime` and therefore which bucket an item belongs in — but it may only run once parent/map are final. The vendor, house, lift and drop sites already satisfy that. The rest of this PR fixes the ones that did not, plus what the audit turned up:
- **`Item.Deserialize`** stamped via `SetLastMoved()` before the version data was read, registering against an unread `Map`/`Parent`. Safe only by accident (the `Item(Serial)` ctor leaves flags at 0, so `Decays` is false), and it cost an unregister per item per world load. Now stamps only; `PostDeserialize` does the registration.
- **`Item` constructor** registered then immediately unregistered every item — the `Movable` setter saw `m_Map` still null, so `CanDecay()` was true. Also removes a `Configure`-order landmine: constructing an `Item` before `DecayScheduler.Configure()` would have thrown in `Shared.Start()`.
- **`Container.Destroy`** stamped `LastMoved` immediately before `MoveToWorld`, which now stamps it itself.
- **`Unregister` was documented O(1)** but scanned twelve buckets and did a linear `PriorityQueue.Remove`, on every construction, deserialize and move. Items now record where they are tracked in `Item.DecaySlot` (1 byte), so untracked items — the common case — leave in O(1).
- **A refused decay silently dropped the item.** `ProcessActiveQueue` deleted on `OnDecay() == true` but did nothing when a region refused, leaving the item dequeued, untracked and on the ground forever. It now restarts the decay clock; re-registering as-is would spin, since `ScheduledDecayTime` is already past.
## Two content bugs of the same class
The decay system replaced a polling sweep. Under polling, a `Decays`/`DecayTime` override could read live state every pass. Under a registration model it cannot — the scheduler drops items that stop being eligible, but nothing enrols one that becomes eligible while untracked.
- **`TreasureChestLevel1-4`** overrode `DecayTime` as `Utility.Random(15, 60)` — a fresh roll on every read. `ScheduledDecayTime` is read repeatedly (to bucket, to re-bucket on rotation, to test whether due), so those reads disagreed: the chest re-bucketed every tick and decayed early instead of after its intended interval. Now rolled once per chest. Distribution unchanged — `Utility.Random(from, count)` is RunUO's `from + Next(count)`, so this is 15–74 minutes, as before.
- **`StrongBox`** overrode `Decays` with a live check on `_house`, `_owner.Deleted` and `IsCoOwner`. Nothing notifies the box when any of those change, so it was never enrolled and the override never decayed anything — and it could not have: `HouseRegion.OnDecay` refuses a secured item inside a standing house, and the box is in `Secures`. Decay was never the mechanism here.
- A strongbox is only ever its owner's. Without a house, or without an owner still co-owning that house, it would be a free container anyone could loot, so `Validate()` destroys it. The old check missed exactly those two cases — it required a non-null owner and treated a null house as valid. A deleted owner deserializes back as null, which `IsCoOwner` rejects. The now meaningless `Decays`/`DecayTime` overrides and an unhelpful `Console.WriteLine` are gone.
`DecayScheduler` now documents both constraints.
## Tests
`DecayRegistrationTests` (Server) covers world placement, lift/drop, container round-trip, cursor-held (must *not* track), `Container.Destroy` spill, `DecaySlot`/structure agreement, refused decay, and a full decay lifecycle driven through the scheduler. `TreasureChestDecayTests` (UOContent) locks `DecayTime`/`ScheduledDecayTime` stability across all four chest levels.
To make the lifecycle testable deterministically, `DecayScheduler` gains `internal` members (visible only via existing `InternalsVisibleTo`): `IsRegistered()`, `ProcessTick(now)` — extracted from `OnTick()` with no behaviour change — and `ResetForTests()`.
Red/green verified. Without the `MoveToWorld` fix, 5 of 6 of the original tests fail, including `ItemOnGround_ActuallyDecaysAfterDecayTime`, which shows a ground item never decays even after a full simulated hour. Without the chest fix, 8 of 8 chest tests fail. Without the refused-decay fix, that test fails.
Server.Tests 737/737 and UOContent.Tests 509/509 pass.
## The bug
#2522 rewrote the outgoing huffman table in `NetworkCompression.cs` and transposed symbol `0x19`'s code from `0x1CE` to `0x12E` (both 9 bits, so the length distribution — and the Kraft sum — stayed valid, which is why nothing obvious tripped).
The real damage is that it broke prefix-freeness. `0x12E` is `100101110`, and symbol `0x0D`'s 8-bit code is `10010111` — a proper prefix of it. The client's decoder walks the tree bit by bit, so it hit a valid leaf at `0x0D` after 8 bits, emitted the wrong byte, and then reframed every subsequent code.
That is exactly what the reporter's capture shows. Server sends `BF 00 0C 00 19 02 00 00 00 01 00 00`; the client's post-decompression stream reads `BF 00 0C 00 0D 55 00 00 01 00 00` — the literal `0D` is the mis-decoded `0x19`, and the packet is now one byte short, so framing desyncs from there on.
## Impact
Any outgoing packet with byte `0x19` anywhere in its body (serials, coordinates, hues, lengths, text) corrupted the stream. Because the desync is in framing rather than a single field, the client silently stops applying server updates while still being able to send — no disconnect, no error.
`StatLockInfo` (`0xBF` subcommand `0x19`) is sent during login, so it reproduces on essentially every connection. This is also #2526: "can only walk a few steps, then the client stops responding" is the same desync, not a VPS sizing problem.
## Fix
One entry, restored to the canonical value:
```diff
- 0x9, 0x191, 0x9, 0x12E, 0x7, 0x03F, ...
+ 0x9, 0x191, 0x9, 0x1CE, 0x7, 0x03F, ...
```
## Validation of the whole table
Rather than eyeball 257 entries, I diffed the current table against **every revision of it in this repo's history** — all 34, back through the renames to the original import. All 34 agree with each other, and `0x19` is the sole disagreement with #2522's rewrite. No other entry has ever changed.
I also validated the table structurally: all 257 lengths in `[2,11]`, every value fits its declared bit-length, Kraft–McMillan sum exactly 1, and no code is a prefix of any other. It passes on all counts now, and the prefix check is what located the bug in the first place.
Both checks were one-off validation scripts, not committed — see below.
## Test
A single known-answer test (`~10ms`) that compresses all 256 symbols and asserts the exact output bytes. The expected bytes were generated from the canonical table, *not* from the implementation, so the test isn't circular. Any single wrong table entry changes the output, so it pins all 256 entries plus the terminal code, and it exercises the encoder end to end.
A round-trip test would **not** catch this class of bug — encoder and decoder built from the same table agree with each other even when the table is wrong. The contract being violated is with the client's hard-coded tree, so the expected bytes have to come from outside the implementation.
The structural prefix-free check and a second `StatLockInfo` vector were deliberately dropped after they'd served their purpose: the table is now verified and effectively frozen, so the structural check was guarding a constant, and the `StatLockInfo` vector is a strict subset of the all-symbols one. What remains covers the risk that's still live — `Compress` is a hand-unrolled bit-packing loop that will get optimized again, and this is the guard against that rewrite silently corrupting the wire format, which is precisely what happened here.
Verified the test fails when the bug is reintroduced and passes when fixed. Full `Server.Tests` suite green: 727 passed.
## At a glance
```csharp
public override void GetProperties(IPropertyList list)
{
base.GetProperties(list);
// Accumulate any number of free-text lines. On dispose the block flushes via
// AddChunked, splitting across as many OPL properties as needed so none can
// overflow the legacy 2D client's per-property buffer (which would crash it).
using var block = list.TextBlock();
if (luck > 0)
{
block.Add($"Luck Bonus: +{luck}%"); // zero-alloc interpolation
}
block.Add("Cannot be repaired".AsSpan()); // plain text, no string allocation
// Already holding a '\n'-joined string? Skip the builder and chunk directly:
// list.AddChunked(description);
}
```
## What
Adds a safe path for emitting **variable-length, free-form (non-cliloc) tooltip text**:
- **`ObjectPropertyList.Add(ReadOnlySpan<char>)`** overloads — append raw text with no string allocation. Makes the old single-arg `Add(string)` redundant (a `string` binds to the span overload implicitly), so it's dropped.
- **`AddChunked(ReadOnlySpan<char>)`** on `IPropertyList` — splits newline-joined text at `\n` boundaries across as many passthrough-cliloc properties as needed, so no single property exceeds the cap.
- **`OplTextBlock`** (`ref struct`) + **`IPropertyList.TextBlock()`** — an ergonomic builder that accumulates `\n`-joined lines (with a zero-alloc interpolated `Add($"...")` overload) and flushes via `AddChunked` on dispose. Usage: `using var block = list.TextBlock();`.
- **`MaxArgumentLength` (504)** — per-property cap with a hard backstop that clamps + logs anything that slips through.
## Why
The legacy 2D client copies each OPL property's text into a fixed ~512-char (1024-byte) buffer. A single property longer than that smashes an adjacent world object's vtable on the client heap and crashes the client. `AddChunked`/`OplTextBlock` keep multi-line content safely under the cap instead of risking one oversized `Add`.
## Docs
- `dev-docs/property-lists.md` — new "Multi-Line Free Text" deep-dive section; corrected the stale `IPropertyList` listing.
- `dev-docs/claude-skills/modernuo-property-lists.md` — condensed pattern + anti-pattern.
## Tests
9 tests pass (`OplTextBlockTests`, `ObjectPropertyListSpanAddTests`): line joining, empty-line skipping, no-line no-op, zero-alloc interpolation, and long-content chunking staying under `MaxArgumentLength`. Full `UOContent` build is green, confirming dropping `Add(string)` breaks no call sites.
## 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.
## Summary
Removes the dated `DynamicJson` JSON helper and migrates spawner JSON (de)serialization to a polymorphic `record SpawnerDto` hierarchy. `DynamicJson` was the last remaining consumer (regions moved off it in #1400).
The key correctness improvement: **System.Text.Json deserializes plain DTO records, never a live `Item`.** Previously, deserializing directly into an `Item` meant STJ constructed world-registered objects *before* the data was validated — a malformed/hand-edited spawn file could leave orphaned spawner Items in the world save. Now a parse failure is GC-only; `dto.ToSpawner()` constructs the spawner only from a fully-validated DTO and self-cleans on failure.
## What changed
- **New:** `SpawnerDto` (abstract) + `SpawnerDataDto` / `RegionSpawnerDto` / `ProximitySpawnerDto`, each marked with a reusable `[JsonDiscoverableType]` opt-in attribute. Auto-discovered at the `Configure` phase — no manual registration list (avoids the regions `Register<T>()` footgun), open to custom spawner subtypes.
- **Symmetric mapping:** `BaseSpawner.ToDto()` (export) ⇄ `SpawnerDto.ToSpawner()` (import). `ToSpawner()` deletes-and-rethrows on any failure, so the importer can never orphan an Item.
- **`SpawnerJsonSerializer`** wires `$type` polymorphism on the `SpawnerDto` root with loud collision/constructibility validation.
- **Import/export commands** rewired to the typed DTO path (reflection `FindTypeByName`/`CreateInstance` removed).
- **Data migration:** the 109 `Distribution/Data/Spawns/**` files moved from `"type"`→`"$type"` and legacy `homeRange`→`spawnBounds`. The runtime still *reads* legacy `homeRange` for external files. The `homeRange→spawnBounds` formula is proven equivalent to the runtime conversion (`BoundsEquivalenceTests`, hr=0/1/3/7).
- **Deleted:** `Projects/Server/Json/DynamicJson.cs`.
Sparse export output matches the legacy `ToJson` (nullable DTO properties + `WhenWritingNull`). Binary world-save serialization is untouched.
## Tests
- DTO round-trip per spawner type; sparse-default omission; legacy `homeRange` read; export/import file round-trip.
- `Import_MalformedFile_LeaksNoWorldItems` — proves a mid-array parse failure constructs zero world Items.
- `AllSpawnFilesLoadTests` — every migrated spawn file deserializes and builds.
- Duplicate-discriminator validation.
- UOContent.Tests 485/485, Server.Tests 710/710, build clean.
## Follow-up (not in this PR)
`Rectangle3DConverter.Write` (in `Projects/Server/`) omits `z1/z2` when `Start.Z == -128`, so a future server-side export of a `homeRange`-style spawner round-trips depth 256→255. Pre-existing and out of scope here (Server change); the migrated data reads correctly. Worth a separate small converter PR.
## Problem
A creature equipped with two items that resolve to the **same layer** can crash the legacy EA 2D client (use-after-free). Equipment `Layer` comes from tiledata (`Layer = (Layer)ItemData.Quality`), so a **two-handed weapon and a shield both resolve to `Layer.TwoHanded`**. `Mobile.FindItemOnLayer` even documents the invariant: *"We only allow 1 item per layer. Its an implicit contract."*
## Root cause
- `SendMobileIncoming` (0x78) **dedupes by layer** (the `layers` span) and sends only the first item per slot — so a static creature is fine.
- But the per-item **`SendEquipUpdate` (0x2E)** and the item **OPL** sends do **not** dedupe. On any equip/property delta (`Item.ProcessDelta`) they fire per item and leak the second same-layer item on its own.
- The client then holds two items on one equipment slot; when that slot is torn down (e.g. a large group of such creatures and the player runs out of range → mass remove) the legacy 2D client frees one and dereferences it → UAF. ClassicUO bounds-checks and is unaffected, but the server is emitting an invalid, self-contradictory stream either way.
## Fix
Make per-item equip/OPL sends honor the same first-item-per-layer rule `SendMobileIncoming` already uses:
- `Item.IsDupedEquipLayer()` — `m_Parent is Mobile m && m.FindItemOnLayer(m_Layer) != this` (reuses the existing helper; true when an earlier item already holds this items layer).
- `Item.ProcessDelta`: early-return before the per-client loop for a duped equipped item (skips the EquipUpdate and OPL to everyone).
- `Mobile` lift-reject re-show: skip the EquipUpdate and OPL for the dupe.
No behavioral change for valid equipment (distinct layers → never duped). For the invalid duped-layer case the second item was already omitted by the 0x78 packet; this just stops it leaking back via the per-item paths.
## Problem
Houses and boats (multis) were pathed correctly only by **delegation to the slow path**: `StepCache.TryGetMask` returns `Fallthrough_Multi` for any multi-covered cell, and `GetSuccessors` ran `CheckMovement` **8× per cell** (each re-resolving the tile stack via `GetStaticAndMultiTiles`) — a sustained per-step cost near every house/boat. There was also no automated test pinning multi pathfinding.
This branch is the full multi-pathfinding effort in phases on one branch.
## Phase 1 — characterization tests (the oracle)
Implementation-agnostic invariants: a cache-on≡cache-off whole-path invariant, a per-cell sweep vs `CheckMovement` over footprint+halo (incl. destination Z), hand-verified routing (around walls, demolish-reopens, foundation-redesign-honored), classic-house / foundation / boat fixtures, non-vacuity guards. These gate every later phase byte-for-byte.
## Phase 2 — live single-pass synthesizer
`StepProbe.ComputeMultiMaskAt` synthesizes a covered cell's full 8-direction `StepMask` in one pass (the existing surface/step logic over `GetStaticAndMultiTiles` instead of 8× `CheckMovement`). `GetSuccessors` routes `Fallthrough_Multi` cells through it. No new cache, no `.swb` change. **~1.5×**, zero added allocations.
## Phase 3 / 3.1 — warm per-`multiID` interior cache (airtight)
`MultiMaskCache` caches each fixed multi's local-frame `StepMask` for **interior** cells (cell + all 8 neighbours covered → terrain-neighbour-free → position-invariant), keyed by `multiID & 0x3FFF`, built lazily from the MCL. Interior cells become ~20 ns lookups.
The cache is gated on a **per-instance footprint-clean flag** (`BaseMulti.PathInteriorCacheState`): an instance whose whole footprint terrain is below its floor (`maxTerrain < minFloor`) serves from the cache; a **dirty** instance (terrain intrudes — a contrived/GM placement) **degrades to live-synth, never a wrong mask**. This closes a cross-instance soundness gap (the cached mask depends on neighbour terrain too) found in a holistic review. The gate resets whenever the footprint's world-terrain relationship can change — **location, map, or ItemID** (a boat's heading swaps the MCL).
**Boats are cached too.** Their per-`multiID` deck masks are movement-invariant (built once per heading), so a sailing boat never rebuilds them; only the cheap clean-flag rescan repeats per move (and only when pathed near). Narrow existing boats have little interior; wide galleons (`multi.mul`) would gain Castle-class. `HouseFoundation` (per-instance runtime `DesignState`) is the one type that stays on the live path.
## Verification
- `UOContent.Tests` **454/454**, `Server.Tests` **708/708**, 0 failures.
- The Phase-1 oracle (`MultiPathInvariantTests`, cache-on ≡ cache-off) stays **byte-identical** with the synthesizer + interior cache active.
- Tests pin: footprint-cleanliness (clean vs sunk), dirty/cluttered placement degrades to live-synth while still pathing, clean placement serves, and the gate resets on move/ItemID change.
## Performance (modernuo/ModernUO-Benchmarks#8, full-fixture)
Houses at **Green Acres** (flat staff region → clean footprints, the legit-placement case):
| Route | Slow path | Phase 3.1 (interior cache) | Speedup |
|-------|----------:|---------------------------:|--------:|
| `around_a` (29 steps) | 238.3 µs | **49.1 µs** | **4.85×** |
| `around_b` (29 steps) | 224.3 µs | **49.5 µs** | **4.53×** |
~130 of ~167 multi cells/route serve from the cache (~20 ns) vs 37 live-synth. Per-cell, the slow path's 8× `CheckMovement` grows with multi complexity (GuildHouse ~857 ns → Castle ~1,194 ns), the synthesizer is a flat ~780 ns, and the cache serve is ~20 ns — so big/tall multis (and wide galleons) gain most. Identical allocations throughout.
## Summary
`Mobile.SayTo(Mobile to, int number, string args = "")` always sends the localized message using `SpeechHue`. This adds a parallel overload that accepts an explicit `hue`:
```csharp
public void SayTo(Mobile to, int number, int hue, string args = "") =>
to.NetState.SendMessageLocalized(Serial, Body, MessageType.Regular, hue, 3, number, Name, args);
```
It mirrors the existing localized overload exactly, only substituting the caller-provided `hue` for `SpeechHue`, so content can send a cliloc message to a single mobile in a chosen color without dropping down to `NetState.SendMessageLocalized` directly. This restores the hued-cliloc `SayTo` that RunUO/ServUO content commonly relied on (e.g. `SayTo(from, 1042205, 0x3B2)`).
## Notes
- Purely additive; no behavior change to existing call sites.
- No overload ambiguity: `SayTo(m, num)` and `SayTo(m, num, "args")` still bind to the existing overload; `SayTo(m, num, hue)` binds to the new one (the third positional arg is `int` vs `string`).
- Null-safe to the same degree as the existing overload (`SendMessageLocalized` guards via `CannotSendPackets()`).
## Test Plan
- [x] `dotnet build Projects/Server` — 0 warnings, 0 errors.
- One-line additive overload mirroring an existing (untested) method; no existing `Mobile.SayTo` unit tests to extend. Happy to add coverage if preferred.
## Summary
Fixes the pathfinding step-cache (`.swb`) prebake so it bakes **once** and skips when a valid cache already exists, instead of re-baking on every boot. The root cause was the staleness fingerprint hashing mutable in-memory tile data rather than the on-disk files. This PR makes the fingerprint a pure function of the client data files and separates dynamic multis (houses/boats) from the static cache.
> This branch builds on the `ConfigurePrompts` first-boot-prompt unification (commit `5df8d0bd`, also included here) — that commit accounts for the `ServerConfiguration.cs` and `dev-docs/server-lifecycle.md` changes in the diff.
## The bug
With `pathfinding.prebakeMaps` set, the cache re-baked on **every** boot. The `.swb` staleness fingerprint hashed the live `TileData.LandTable`/`ItemTable` flags, which the server patches at runtime (`ItemFixes`, `LOSBlocker`, `PotionKeg`, `CTF`) at nondeterministic lifecycle points (Initialize-phase methods share a priority; static ctors fire lazily). So a fingerprint stamped at runtime (`[PathBake`) never matched the one recomputed during startup `Initialize()`, and the cache rebaked every time.
## Changes
**1. Fingerprint the files, not the in-memory tables** (`fix`)
Hash `tiledata.mul` (cached, computed once) plus the per-map `.mul`/`.uop` files — never the runtime-mutated `TileData` tables. The fingerprint is now lifecycle-stable. Existing `.swb` files rebake once after deploy, then stay stable.
**2. Compute the fingerprint once per boot** (`refactor`)
`Configure()`'s `AutoLoadAtStartup()` already opens and fingerprint-validates a reader for every up-to-date `.swb`. `Initialize()` now skips baking any map that already has an open reader (`StepCache.HasLazyReader`) instead of recomputing the fingerprint a second time.
**3. Bake static-only; route multis to the live path** (`refactor`)
Multis (houses/boats) are dynamic, so they're no longer baked into the static chunk cache — they were tagged with `BuiltMultisVersion`, a non-persisted session counter, which made persisting them unsafe (false matches / wasted re-bakes).
- Chunks bake land + `statics.mul` only.
- At query time, any cell whose sector (or its 1-cell halo) contains a multi routes to `Fallthrough_Multi` → the existing live, multi-aware `CheckMovement` path. The halo prevents a cell proposing a walkable edge into a neighbouring wall; interior (multi-free) cells pay one sector lookup.
- Adds `Sector.HasMultis` (one engine accessor); `.swb` format → v9 (rejects old multi-baked files); new `Fallthrough_Multi` telemetry.
- Behaviour-preserving: multis use the same live path the engine used before the cache existed.
**4. Comment polish** (`style`) — no behaviour change.
## Testing
All green: **92** pathfinding (incl. a new fingerprint-stability test and a multi-halo fallthrough test), **423** UOContent, **708** Server.
## Follow-ups (not in this PR)
- **Background bake worker** — make `[PathBake` and the boot prebake non-blocking (game thread serves tile reads to an off-thread worker).
- **Per-multi MCL cache** — cache walkability in each multi's own frame (keyed by multiID, movement-invariant) so houses/boats get a fast path instead of the live fallback.
- **House-pathfinding equivalence tests** — the one area not yet covered by a dedicated automated test; multi pathing is currently correct by delegation to the live path.
Stacked on #2475 (the `ConfigurePrompts` phase). Base will switch to `main` once #2475 merges.
## What
Move the engine's own first-boot prompts — data directories, listeners, server name, expansion + map selection — out of `ServerConfiguration.Load` and into **`ServerConfiguration.ConfigurePrompts()`** (`[CallPriority(0)]`), so **all** first-boot prompting (engine and content) runs through the single `AssemblyHandler.Invoke("ConfigurePrompts")` phase. `Load` now only reads/creates the config file.
## Why it's safe
- **Assembly loading uses `AssemblyDirectories` (default `./Assemblies`), not `DataDirectories`** — so assemblies load fine before the now-later data-dir prompt. This is the linchpin that makes the move possible.
- **`UOClient.Load()`** (client-file discovery via `Core.FindDataFile`) needs `DataDirectories`, so it moved *with* the data-dir prompt into `ConfigurePrompts`.
- **`Core.Expansion`** is now assigned in `ConfigurePrompts` (every non-mocked boot). Nothing between `LoadAssemblies` and that phase reads it — type initializers run lazily on first use, not during `LoadAssemblies`.
- **`[CallPriority(0)]`** keeps the engine prompts (including map selection) ahead of content prompts such as the pathfinding pre-bake (priority 50), preserving "after map selection".
- `Main.cs` already invokes the phase — **no startup-ordering edit** here.
## Tests
`Server.Tests` **708/708**, `UOContent.Tests` **418/418**, build clean. Fixtures are unaffected: they call `Load(true)` (now just reads config) and set expansion/data dirs directly; `ConfigurePrompts` is gated on `m_Mocked`.
## ⚠️ Needs first-boot runtime verification
`Main.cs` startup ordering is **not** covered by the fixture-based suite (the fixtures bypass `Main`). Please boot once with a fresh `modernuo.json` to confirm the first-boot prompt sequence (data dirs → … → expansion/maps → pathfinding pre-bake) and that `Core.Expansion` resolves correctly. Docs updated in `dev-docs/server-lifecycle.md`.
## Summary
Adds authentic **T2A-era (pre-UO:Third-Dawn) packet-based crafting menus**, enabled via the **`t2aCraftMenus` server setting** (read once at startup; default **`!Core.UOTD`**, so a pre-UO:TD shard gets them automatically). When enabled, double-clicking a crafting tool opens the classic `0x7C`/`0x7D` item-list menu — skill- and material-filtered — instead of the modern gump, covering all 8 tool/skill crafts (blacksmithy, tailoring, tinkering, carpentry, alchemy, bowcraft/fletching, inscription, cartography). It is **not** a runtime/admin-flippable feature flag.
This is the **definitive, reconciled** branch and **supersedes**:
- **#2181** (Delphi — `T2A_CraftingMenus`): the original effort.
- **#2381** (Jack/UOLL — `t2a_crafting_menus`): the research-grounded superset (Delphi's base + 12 corrections), rebased onto current `main`.
Original authorship is preserved across the cherry-picked history: foundation commit **@Delphi79**, mechanic fixes **@jackuoll (Jack Ward)**, reconciliation/fixes/docs mine.
## How it was built
1. Cherry-picked Jack's 13 commits onto current `main` (superset of Delphi's; only 2 trivial FeatureFlags conflicts).
2. Applied targeted fixes (below) with tests.
3. Full convention audit, build, and test pass.
Grounded in independent historical research plus Jack's deep dive. Maintainer reference: `dev-docs/t2a-crafting.md`.
## Mechanics (highlights)
- Double-click tool → target resource → skill/material-filtered menu → craft. Resource pre-selection per skill; make-last by targeting the tool.
- **Stacked-gem jewelry:** target a gem stack → the **full stack** is consumed and the piece is named by count ("a 1000 diamond ring"); count persists (`BaseJewel` serialization **v4 → v5**, new `_gemCount`).
- **Tool-less inscription & cartography** (skill-list invoked; no pen/sextant); inscription consumes reagents+scroll on success and failure, mana only on success.
- **Tailoring matching-hue consumption:** targeting hued cloth/leather consumes only that hue. Crafted items take color from their **`CraftResource`** (not the dyed hue), so dyed leather/cloth don't tint the product; in T2A only colored ingots/ore color items (metal armor/shields).
- **Half-resources on failed non-scroll crafts** (pre-UO:TD).
- **Maker's mark** always prompted for exceptional items, via the shared `QueryMakersMarkGump`.
- Server-side menu infra changes are additive (`ItemListEntry.CraftIndex`, `Entries` setter, `HasSent`).
## Notable changes on top of the cherry-pick
- **Toggle is a startup server setting, not a feature flag.** Removed `ContentFeatureFlags.T2ACraftMenus` (and its admin-flippable plumbing); the value is read once via `ServerConfiguration.GetSetting("t2aCraftMenus", !Core.UOTD)` into `T2ACraftSystem.Enabled`. Since the default tracks the era and it can't be flipped at runtime, there's no incoherent "menus-on / UO:TD-era" state.
- **Stacked-gem consumption (B3a/B3):** consume the full `PendingGemCount` (was deliberately consuming 1 while naming by the stack), null-safe gem type, plain-piece fallback + message. New `T2AJewelGemCraftTests`.
- **Convention audit:** `new List<Item>()` → `PooledRefList<Item>` on the hue-aware consume path; removed dead code.
## Decisions & deviations
- `make-last` kept as **QoL** (post-T2A gump-era feature).
- `half-on-failure` (non-scroll) kept as a **reconstruction** (not OSI-confirmed).
- **Stacked-gem** behavior set per shard authority (overrides the "single gem" reconstruction).
- **Cooking** out of scope (no T2A crafting menu existed for it).
- **No colored items from dyed materials:** crafted color comes from the `CraftResource` type. Pre-AOS leather has no colored variant, so leather is always uncolored; weapons retain resource color only in AOS+ (unchanged, intended).
## Test plan
- Automated: `dotnet build ModernUO.slnx -c Debug` clean; `dotnet test Projects/UOContent.Tests` → **421 passed** (incl. 3 new jewelry tests).
- Manual (needs a running T2A shard + client):
- [ ] Each of the 8 skills opens the correct menu; empty-menu guard fires.
- [ ] Make-last repeats the last craft (jewelry re-prompts gem).
- [ ] Jewelry consumes the full targeted gem stack and names by count.
- [ ] Cartography consumes blank maps only with T2A enabled / maps+scrolls when disabled.
- [ ] Tailoring consumes only the targeted-hue material; crafted items are not tinted by dyed cloth/leather.
- [ ] Maker's-mark prompt on exceptional.
- [ ] Failed non-scroll craft consumes half resources.
- [ ] Inscription: reagents+scroll on success/failure, mana only on success.
- [ ] T2A disabled: gump crafting unchanged.
## Credits
Co-authored-by: @Delphi79
Co-authored-by: @jackuoll
## What
On **first boot** (right after map selection), offer to pre-bake the pathfinding `.swb` cache for the selected maps. This removes first-pathfind-after-boot latency and is now cheap — ~18 MB/facet after the v8 format work (the old ~565 MB is gone). The answer persists in `modernuo.json` as **`pathfinding.prebakeMaps`** (default **false**): asked exactly once, and skipped on headless/CI boots (redirected input) where operators can set the flag directly.
## How — a generic startup phase, not pathfinding hardcoded in the engine
The clean-console (pre-Serilog) prompt window is inside the engine startup, but UOContent isn't loaded until after `ServerConfiguration.Load`. So rather than coupling the engine to pathfinding, this adds a generic lifecycle phase:
- **`Main.cs`**: new `AssemblyHandler.Invoke("ConfigurePrompts")` — runs **after** `LoadAssemblies` (so content can participate) but **before** the first `logger.Information` (so console prompts aren't interleaved with the async console sink). The first log line moves below it. Any class can hook in with `public static void ConfigurePrompts()` and self-gate on first-boot state. No `ServerConfiguration` or pathfinding coupling added to the engine.
- **`PathCacheCommands.ConfigurePrompts()`**: the first-boot prompt (interactive-only, flag-absent-only); persists the answer.
- **`PathCacheCommands.Initialize()`** (`Invoke("Initialize")` phase, after the tile matrix loads — which the bake walks): when the flag is set, bakes any map whose `.swb` is **missing or stale** (tile-data fingerprint mismatch, via `StepCache.ComputeLiveFingerprint` / `TryReadFingerprintFromFile`). A fresh cache is a no-op, so only the first boot — or a post-client-update boot — pays the several-minute cost.
## Docs
Fixed the now-stale "~565 MB / ~1.5–2 GB / do not bake by default" section in `dev-docs/pathfinding.md` (it's 17.9 MB for Trammel, tens of MB for all six facets after v8), added a "First-boot pre-bake prompt" section, and added the `pathfinding.prebakeMaps` lever row.
## Verified
- `dotnet build UOContent -c Release` → 0 errors (rebased on #2474).
- Pathfinding/StepCache tests: **90/90 pass**.
- Bootstrap streamlining of the startup phases is intentionally left as a follow-up.
## Problem
Running the full `UOContent.Tests` suite, the test host **hangs ~2.5 minutes at shutdown and then crashes** (`Test host process crashed` / run aborted). The tests themselves are fine — they complete in ~1s — but the process can't exit.
Captured via `--blame-hang` dump. The blocking thread:
```
System.Threading.WaitHandle.WaitOne()
Server.SerializationThreadWorker.Sleep() SerializationThreadWorker.cs:54 (_stopEvent.WaitOne())
Server.SerializationThreadWorker.Exit() SerializationThreadWorker.cs:61
Server.World.ExitSerializationThreads() World.cs:429
Server.Tests.UOContentFixture..ctor()
```
### Root cause
Both collection fixtures (`UOContentFixture` and `PathfindingTestFixture`) each run the **full process-global ModernUO bootstrap**. `World.Load()` is guarded to run once per process, so the **second** fixture's `World.Load()` is a no-op and does **not** respawn the serialization workers — but `World.ExitSerializationThreads()` is **not** guarded, so the second fixture calls `Exit()` on workers whose threads have already terminated. `Exit()` → `Sleep()` → `_stopEvent.WaitOne()` then blocks forever (a dead thread never sets the event). The first collection's tests run; the second collection's fixture deadlocks in its constructor; the host eventually gets killed.
This is why single-collection (filtered) runs were fine — only one fixture ever bootstraps — but the full suite hangs. It's not a parallelization race: even strictly sequential, the second fixture deadlocks.
## Fix
**(a) Engine — idempotent `SerializationThreadWorker.Exit()`**
A second `Exit()` is now a safe no-op instead of a permanent block. Only the owning (main) thread calls `Exit()`, so no synchronization is needed, and the single-call production shutdown path is unchanged.
**(b) Tests — one shared bootstrap, strictly sequential collections**
- New `TestServerBootstrap.EnsureInitialized()` runs the superset global init **exactly once per process** (lock + once-flag).
- `UOContentFixture` / `PathfindingTestFixture` slim down to delegate to it and no longer tear down global state (which the single-bootstrap model owns for the host's lifetime).
- `[assembly: CollectionBehavior(DisableTestParallelization = true)]` so collections never overlap.
## Result
| | Before | After |
|---|---|---|
| Tests run (full suite) | 258 (UOContent collection deadlocked) | **418** |
| Outcome | 2.5-min hang → host crash | **418 passed, clean exit** |
| Wall time | killed | **~7s** |
## Summary
Phase #3b (final roadmap item), stacked on #2470. Compacts the index trailer from 20 to 8 bytes/chunk.
Trammel: 19.2 MB → 17.9 MB. Roadmap total: 565 MB → 17.9 MB (−96.8%).
## Details
- Trailer stores `{ u32 packedKey = (ChunkX << 16) | ChunkY, u32 recordLength }` per chunk, in record write order; the file offset is dropped and reconstructed by cumulative recordLength from HeaderSize.
- No record reordering, no varint; fixed-stride, TryReadChunk unchanged.
- Also simplifies the accumulated `.swb` code comments across the stack.
- Format v8; v7 files rejected and re-baked once.
## Tests
v8 multi-chunk round-trip (cumulative offset reconstruction) + the v6/v7 suite; full pathfinding suite green; Release build clean.
## Summary
Phase #3a, stacked on #2469. Compresses each chunk record independently with libdeflate (random access preserved).
Trammel: 124.7 MB → 19.2 MB (−85%).
## Details
- Whole-record framing `[u32 UncompressedLen][payload]`; records that don't shrink (tiny Uniform) are stored raw, detected as payload length == UncompressedLen.
- Codec chosen by full-Trammel spike: libdeflate VeryHigh (16.5 MB, 1.83 µs/chunk decompress) over zstd L19/22 (17.4 MB) and managed Brotli q11 (16.4 MB) — best native ratio, fastest decompress, already the repo's packet codec (no new dependency).
- Reuses cached thread-static bindings: `Deflate.Maximum` for bake, `Deflate.Standard` for reads.
- Compression is bake-time only; decompression is one-time per chunk (LRU-cached).
- Format v7; v6 files rejected and re-baked once.
## Tests
v7 unit tests + the v6 suite run through the compression path; full pathfinding suite green; Release build clean.
Fixes#2462
## Summary
Removes the per-object `VirtualHairInfo` heap wrapper for mobile/corpse hair. Hair is now stored **inline** on `Mobile` and `Corpse` as `int _hairItemId` / `int _hairHue` plus a lazily-allocated, **non-serialized** ephemeral `Serial _hairSerial` (in the high virtual-serial range) — and likewise for facial hair. The `VirtualHairInfo` class is deleted, with a **lossless** save migration.
This delivers three things:
1. **Fixes a hair-removal bug.** `Delta(MobileDelta.Hair)` is deferred (it enqueues; `ProcessDeltaQueue` runs later in the tick). The old `HairItemID = 0` setter nulled `_hair` *immediately*, so by the time `ProcessDelta` built the remove packet the equipped virtual serial was already gone — the old `??=` code then re-materialized a **fresh** serial (≠ the equipped one), so clients never removed the right entity, and it left a phantom ItemId-0 object behind. The serial now lives on the entity and **persists across removal**, so remove packets carry the correct serial.
2. **Lightens the entity.** No heap hair object; bald mobiles allocate nothing (the serial is minted lazily only when hair is present). This was the original reason `HairItemID`/`HairHue` exist.
3. **Removes `VirtualHairInfo` entirely**, keeping the high-range virtual serial behavior.
## How
- **Mobile** (manual serialization): inline `_hairItemId/_hairHue/_hairSerial` (+facial); lazy `HairSerial`/`FacialHairSerial`; `ProcessDelta` reads those. Serialization **v36 → v37** — the v30-v37 deserialize is unified, reading the legacy per-hair `VirtualHairInfo` version int only when `version < 37`. Setting item id to 0 clears the hue (matching the old object-nulling) while retaining the serial.
- **Corpse** (codegen serialization): decomposed to `[SerializableField] int _hairItemId/_hairHue` (+facial) + ephemeral serial; **v16 → v17** with `MigrateFrom(V16Content)`.
- **Lossless migration:** the loader validates exact byte length, and the old corpse hair is a presence-bool-gated block, so a tiny **migration-only** `LegacyHairInfo` reader (no runtime role) consumes the legacy `[bool][int ver][int itemId][int hue]` bytes. Frozen `Corpse.v14/v15/v16.json` are retyped to it; `v17.json` describes the new int fields.
- All consumers updated to discrete accessors: `OutgoingMobilePackets`, `CorpsePackets`, corpse subclasses (`MilitiaFighterCorpse`, `SchmendrickApprenticeCorpse`), and the packet test mirrors.
- `VirtualHair.cs` renamed to `OutgoingVirtualHairPackets.cs` (the only type left in it after `VirtualHairInfo` was removed).
## Test Plan
- [x] Full solution build: **0 warnings, 0 errors** (`TreatWarningsAsErrors`).
- [x] `Server.Tests`: **708 passed** (incl. new `RemoveHairUsesEquippedSerial` / `RemoveFacialHairUsesEquippedSerial` proving the serial survives removal + hue clears).
- [x] `UOContent.Tests` corpse/hair: **6 passed** (incl. `CorpseHairMigrationTests` asserting the legacy hair bytes are consumed exactly — the loader's length invariant).
- [x] Generated migration code inspected: V14/V15/V16 readers consume the legacy block byte-for-byte; serial never written to disk.
## Upgrade notes
- Old Mobile (v30–v36) and Corpse (v13–v16) saves load losslessly.
- Minor cosmetic-only change: `SchmendrickApprenticeCorpse` hair/facial-hair RNG draws shift order within each pair (same draw count); irrelevant for a quest NPC corpse.
## Summary
Adds two pieces of pathfinding tooling on top of PR #2448's lazy `.swb` infrastructure:
- **`PathfindRecorder`** — admin-toggled JSONL telemetry capture; one record per `BitmapAStarAlgorithm.Find` call. Output format matches the BDN harness corpus, so production traffic can be captured and replayed in benchmarks without an adapter.
- **Public bake helpers on `StepCache`** — `ComputeLiveTileDataHash`, `TryReadTileDataHashFromFile`, `BakeMap`, `ClearResidentChunks`. Lets the benchmark project (and any future bake utility) drive cache fill + persist without exposing internal types.
The companion BDN harness update lives in [ModernUO-Benchmarks#kb/pathfinding-pr4-bench](https://github.com/modernuo/ModernUO-Benchmarks/tree/kb/pathfinding-pr4-bench): porting `Benchmarks/PathfindInGame/` from the `kb/ai_pathfinding` branch to the API shipped in #2446–#2448.
## What's in this PR
### `PathfindRecorder` (`PathfindRecorder.cs`)
- Holds a single `StreamWriter` open while recording; its internal buffer absorbs per-record writes without per-call `File.AppendAllText`.
- Single `bool` check on the hot path; cheap when disabled.
- Disabling flushes + disposes; an IO failure during write also disables the recorder.
- Server config:
- `pathfinding.recorder.enable` — bool, default `false`. Read on boot via `GetOrUpdateSetting`.
- `pathfinding.recorder.path` — default `<basedir>/Data/Pathfinding/recordings/pathfinds.jsonl`.
- Hooked into `BitmapAStarAlgorithm.Find` — runs once per call, does nothing when disabled.
- Admin command: `[PathRecord [on|off|flush|status]` (default `status`).
### Public cache helpers
- `static ulong StepCache.ComputeLiveTileDataHash()` — wraps the file module's hash function for staleness checks.
- `static bool StepCache.TryReadTileDataHashFromFile(string, out ulong)` — peeks at a `.swb` file's hash field (20 bytes).
- `int StepCache.BakeMap(int, string)` — walks every chunk in the map, populates resident set, saves. Offline / fixture use; blocks for many seconds on a full-map walk.
- `void StepCache.ClearResidentChunks()` — drops chunks + zeros counters but keeps lazy readers open. Lets benchmark loops measure "first query after boot" cost across iterations without the lazy-reader reopen overhead.
## Summary
Adds a binary disk format + lazy reader so the step cache can warm-start from a precomputed file without paying chunk-build cost on the first pathfind through a region. **Resident memory stays bounded by `MaxResidentChunks` regardless of file size** — opening a `.swb` reads only the header + chunk-offset index (~16 bytes per indexed chunk), and individual chunks are seeked + deserialized only when `ResolveMissingChunk` asks for them.
The lazy design (vs. an eager bulk load): a 250 MB bake on a RAM-constrained shard never materializes more than the LRU cap (~40 MB at the default 8192-chunk cap), and unwanted regions never enter memory at all.
Builds on PR #2447.
## What changed
- **`StepCacheFile`** — binary reader/writer module. Writer emits header → chunks (offsets recorded) → index trailer, then patches the header's `IndexOffset` field. Reader is `OpenForLazy(path)` returning a `LazyReader` that holds an open `FileStream` + offset dictionary.
- **`StepCacheFile.LazyReader`** — `TryReadChunk(chunkX, chunkY)` does a single seek + bulk read for one record. `Dispose` releases the underlying stream. Files are opened with `FileShare.Read | FileShare.Delete` so admin tooling can replace them.
- **TileData fingerprint via XxHash3.** The `.swb` header carries a hash of `LandTable + ItemTable` flags. Load rejects any file whose hash doesn't match the running server. Computed via `HashUtility.ComputeHash64` (engine-blessed hasher) — adds a `ReadOnlySpan<byte>` overload alongside the existing `ReadOnlySpan<char>` one for parity.
- **`StepCache.SaveToFile(path, mapId)`** — writes resident chunks for the given map.
- **`StepCache.TryOpenLazyReader(path, mapId)`** — opens the file, validates header, holds the reader for the map's lifetime.
- **`StepCache.ResolveMissingChunk`** — now consults the lazy reader before invoking the runtime baker. A loaded chunk whose `BuiltMultisVersion` doesn't match the live sector falls through to the baker (snapshot was made before a multi was added/removed in that sector).
- **`StepCache.Clear` closes lazy readers.** Test cleanup can delete `.swb` files cleanly.
- **Auto-load at startup.** `PathCacheCommands.Configure()` opens `Data/Pathfinding/<mapId>.swb` as a lazy reader for every map.
- **`[PathCacheSave`** / **`[PathCacheLoad`** — admin commands for the same workflow.
- **`pathfinding.maxResidentChunks` shard-tunable.** Read from `server.cfg` at boot via `ServerConfiguration.GetOrUpdateSetting` (default 8192 ≈ 40 MB). Small shards can tune down; large shards with substantial bakes can tune up to reduce eviction churn. Default is written back to `server.cfg` on first boot, matching the engine pattern used by other settings.
## File layout (v1)
```
Header (48 bytes):
u32 Magic = 0x42575300 ('SWB\0')
u32 Version = 1
u32 MapId
u64 TileDataHash XxHash3 over LandTable + ItemTable flags (HashUtility)
u64 BakeTimestamp informational
u32 ChunkCount
u64 IndexOffset file position where the chunk index begins
Chunk records (fixed size, ~5,393 bytes each, +32 if multi-Z):
u16 ChunkX
u16 ChunkY
u32 BuiltMultisVersion
u8 HasMultiZ
byte WalkMask[256], WetMask[256]
sbyte SourceZ[256], WalkZN..WalkZNW[256], SwimZN..SwimZNW[256]
[byte MultiZCells[32] when HasMultiZ == 1]
Index trailer (16 × ChunkCount bytes):
(u64 chunkKey, u64 fileOffset)
```
## Memory math
| Scenario | Disk file | RAM at boot | Notes |
|---|---|---|---|
| Empty / no `.swb` files | — | 0 | Silent; cache builds on demand. |
| Admin-curated towns (5K chunks) | 25 MB | 0 + per-query | Index ≈ 80 KB. Resident grows to the configured cap under steady-state queries. |
| Full-map bake (50K chunks) | 250 MB | 0 + per-query | Index ≈ 800 KB. Same configured cap. Cold areas never load. |
| All 5 maps fully baked | 1.25 GB | 0 + per-query | Index ≈ 4 MB total. Same configured cap. |
## Hash choice (FNV-1a → XxHash3)
The original draft used inlined FNV-1a-64. Switched to XxHash3 via `HashUtility`:
- ~30× faster on this workload (~30 GB/s SIMD vs ~2 GB/s byte-by-byte). Boot-time only, so absolute saving is microseconds — the real wins are elsewhere.
- Stronger collision resistance and distribution.
- Drops ~25 lines of inlined hash code; matches the rest of the codebase's hashing pattern.
- Hash is stable as long as `HashUtility`'s `xxHash3Seed` constant doesn't change (already marked `// DO NOT CHANGE THIS NUMBER`).
## Summary
Replaces `FastAStarAlgorithm` with `BitmapAStarAlgorithm`: one cache lookup per cell expansion (8-direction mask + per-direction destination Z) instead of 8 separate `MovementImpl.CheckMovement` calls. Adds the supporting cache infrastructure to back it.
Public API unchanged — `MovementPath` / `Mobile.Move` / `CalcMoves.Find` return the same shapes; the algorithm swap is internal.
## What's in this PR
- **`BitmapAStarAlgorithm`** — A* that issues one `StepCache.TryGetMask` call per cell expansion. Inline fallthrough to the per-cell slow path for multi-Z, off-map, source-Z mismatch, and non-default walkers.
- **`StepCache`** — singleton chunk store keyed by `(mapId, chunkX, chunkY)`. Lazily built on first query, invalidated by `Sector.MultisVersion` mismatch, memory-bounded by sampled probabilistic LRU.
- **`StepProbe`** — computes static-only walkability for a single cell, mirroring `MovementImpl.Check` minus the item / mobile collision phases.
- **`StepMask` / `StepChunk`** — value / storage types for the per-cell results.
- **`CacheEvictionTimer`** — periodic cap backstop (60s interval; early-returns when not over cap).
- **`Map.Sector.MultisVersion`** promoted to `public` so the cache can detect dynamic-static invalidations cheaply.
## Eviction strategy
Sampled probabilistic LRU (Redis-style). Per eviction, sample 5 random keys from a parallel `List<long>` kept in lockstep with the chunk dictionary; evict the oldest of the sample via swap-and-pop. O(1) per eviction regardless of resident count, so sustained cap pressure has no perpetual perf hit.
## Capability handling (interim)
Non-default walkers (non-GM players, creatures with `CanSwim` / `CanFly` / `CanOpenDoors` / `CanMoveOverObstacles`) route entirely through the per-cell slow path via `BitmapAStarAlgorithm.GetSuccessorsSlowPath`. The 2-pass design (cache + capability overlay + dynamic-obstacle pass) lands in the follow-up PR.
## Summary
Phase 3 PR B of the message-interpolation cleanup. Handles the multi-line restructure sites flagged in `dev-docs/string-handling-message-interp-audit.md` (Phase 2). Phase 3.1 (PR #2436) handled trivial sweeps; this PR handles sites that needed an `if/else` hoist or switch restructure to eliminate `string.Format` while preserving exact message text.
Each site previously allocated an intermediate `string.Format(...)` result before passing to the message handler, despite Phase 1 making the handler accept interpolated string handlers natively.
## Sites fixed
- **`Projects/Server/Mobiles/Mobile.cs:7911`** - Title/guild header was using `string.Format` with a conditional template (`"[{1}]{2}"` vs `"[{0}, {1}]{2}"`). Split into `if (title.Length <= 0)` / `else` with direct `$"..."` interpolation.
- **`Projects/UOContent/Engines/ConPVP/DuelContext.cs:1337`** - View-ladder rank text used `string.Format(text, from == pm ? "You" : "They")`. Split into `if (from == pm)` / `else` with direct `$"..."` interpolation in each branch.
- **`Projects/UOContent/Engines/ConPVP/DuelContext.cs:1463`** - Showladder text reused a single format string for both `LocalOverheadMessage` ("You ... are ...") and `NonlocalOverheadMessage` ("`{pm.Name}` ... is ..."). Each call now uses an inline `$"..."` directly; no shared template.
- **`Projects/UOContent/Engines/ConPVP/Gumps/ConfirmSignupGump.cs:518`** - The signup confirmation message used a `switch` expression assigning a literal format string to `fmt`, then `string.Format(fmt, from.Female ? "Lady" : "Lord", timeUntil)`. Converted to a `switch` statement where each case calls `_registrar.PrivateOverheadMessage(...)` directly with an inline `$"..."`. Lady/Lord branching is hoisted to a `title` local.
## Exempted
- **`Projects/UOContent/Engines/ConPVP/Participant.cs:138`** - The `nonLocalOverhead` format string is a parameter passed in by callers of `Participant.Broadcast`. Investigation found 5 call sites in `DuelContext.cs` (lines 782, 802, 1187, 1196, and three at 1535/1564/1608) that pass distinct literal format strings. Refactoring would require changing all 5 callers and the method signature - out of scope for this PR. Marked with a `// Phase 3 audit:` comment per the audit's exemption convention.
## Summary
Phase 3.1 of the message-interpolation optimization series. Fixes 9 of the 28 sites flagged in the Phase 2 audit (PR #2435):
| File | Fix |
|---|---|
| `Commands/StaffAccess.cs:88,99` | Drop redundant `.ToString()` on enum holes |
| `Commands/Handlers.cs:102` | `builder.ToString()` -> `builder.AsSpan()` |
| `World Saves/SaveCommands.cs:71-75` | Merge 3 concatenated `$"..."` into one literal |
| `Server/Items/Item.cs:4213` | Hoist nested ternary `$"..."` to if/else |
| `Engines/Factions/Mobiles/Guards/BaseFactionGuard.cs:140-150` | Convert switch expression to switch statement |
| `Mobiles/Monsters/LBR/Jukas/JukaLord.cs:85` | Restructure `string.Format(toSay.RandomElement(), ...)` into switch |
| `Misc/AttackMessage.cs:30-41` | Inline `AggressorFormat`/`AggressedFormat` constants |
No functional changes. Each site emits identical text; the only difference is that the message string is now built into a pooled char buffer instead of being allocated as a `string` first.
## Summary
Adds a custom `:L` format specifier to `RawInterpolatedStringHandler`. When the format string is `"L"`, the handler lowercases the formatted value's chars in-place after the underlying `ISpanFormattable.TryFormat` / `IFormattable.ToString` path completes. Zero allocation, single-pass.
## Usage
```csharp
mob.SendMessage($"You earned a {rank:L} trophy!"); // "gold"
mob.SendMessage($"Welcome, {playerName:L}"); // lowercased
mob.SendMessage($"{count:L} kills"); // ints unchanged ("42")
```
## Motivation
Eliminates the `value.ToString().ToLowerInvariant()` two-allocation idiom that appears across the codebase for any type that goes through an interpolation handler. After this lands, content code can use the `:L` specifier directly instead of helper extensions or per-enum lookup tables.
## Coverage
- `AppendFormatted<T>(T value, string? format)` — generic path (covers IFormattable, ISpanFormattable, .ToString fallback)
- `AppendFormatted(ReadOnlySpan<char> value, int alignment, string? format)` — span path with alignment-aware lowercase range (only the value range is lowercased, not padding)
- `AppendFormatted<T>(T value, int alignment, string? format)` and `AppendFormatted(string? value, int alignment, string? format)` and `AppendFormatted(object? value, int alignment, string? format)` — inherit via delegation
The `format == "L"` comparison is case-sensitive — `:l` (lowercase L) is NOT recognized. `:L` matches the convention of e.g. `:N0` / `:F2` (numeric format specifiers traditionally use uppercase). `char.ToLowerInvariant` is used (not locale-dependent) for predictable game text.
## Future cleanup
Phase 3.3 (#2438) introduced a per-enum `TrophyRank.LowerName()` extension to eliminate `rank.ToString().ToLower()` allocations at 10 ConPVP sites. Once this PR lands, those sites can be simplified to `{rank:L}` and the `TrophyRankExtensions` helper can be removed. Tracked as a follow-up.
## Summary
Phase 1 of a multi-phase optimization to eliminate intermediate string allocations between `$"..."` interpolation and the packet text region for ModernUO's player-facing message APIs.
- Adds `[InterpolatedStringHandler]` overloads to every `Send*`/`Public/Local/Private/NonlocalOverheadMessage`/`Say`/`Emote`/`Whisper`/`Yell`/`SendLocalizedMessageTo` API in `OutgoingMessagePackets`, `Mobile`, and `Item`. Each overload is a 3-line shim that forwards `handler.Text` to the existing span-based path then calls `handler.Clear()` to return the rented `STArrayPool<char>` buffer (matches the established `SpanWriter.WriteAscii(ref RawInterpolatedStringHandler)` precedent).
- Converts `string text/args/affix/name` parameters to `ReadOnlySpan<char>` for consistency with the handler path. `lang` intentionally stays `string` (it's never interpolated and the `??= "ENU"` fallback stays cleaner).
- Adds `int charCount` overloads of the three `GetMaxMessage*Length` helpers so stackalloc sizing can avoid the redundant `ROS<char>` round-trip.
- Moves `Mobile` (17 methods) and `Item` (4 methods) message methods into new partial-class files (`Mobile.Messages.cs`, `Item.Messages.cs`) for organization.
No UOContent call sites change in this PR — existing `string`/`ROS<char>` calls compile unchanged via implicit conversion. Phase 2 (intermediate-string audit) and Phase 3 (cleanup PRs) follow.
## Files
- `Projects/Server/Network/Packets/OutgoingMessagePackets.cs` — `string` → `ROS<char>` for text params, `int charCount` length helpers added, class made `partial`
- `Projects/Server/Network/Packets/OutgoingMessagePackets.Interpolated.cs` (new) — 3 `ref RawInterpolatedStringHandler` extension overloads
- `Projects/Server/Mobiles/Mobile.cs` — message methods extracted (-262 lines)
- `Projects/Server/Mobiles/Mobile.Messages.cs` (new, 463 lines) — moved + ROS-converted methods + 25 handler overloads
- `Projects/Server/Items/Item.cs` — message methods extracted (-93 lines)
- `Projects/Server/Items/Item.Messages.cs` (new, 142 lines) — moved + ROS-converted methods + 4 handler overloads
- `Projects/Server.Tests/Tests/Network/Packets/Outgoing/MessagePacketTests.cs` — 3 new regression tests verifying byte-equivalence for the handler overloads
## Summary
Migrates the Old Guild System (pre-AOS guild stones) gumps from the legacy `Gump` class to `DynamicGump`, following the same pattern used for the Quest gump migration in #2416. All concrete gumps now have private constructors gated by static `DisplayTo` entry points (empty-gump rule), and `Singleton => true` is set across the board so reopening a sibling dialog automatically closes the previous one.
**Migrated gumps:**
- `GuildGump` - main guild dialog
- `GuildmasterGump` - guildmaster functions
- `GuildCharterGump` - charter and website display
- `GuildWarGump` - warfare status (kept as player-facing)
- `GuildWarAdminGump` - war menu (retained as player-facing - reachable from `GuildmasterGump`'s WAR button by guildmasters)
- `GuildChangeTypeGump` - Standard/Order/Chaos selection
**Abstract bases:** `GuildListGump` and `GuildMobileListGump` keep their shared list-rendering chrome inside a single concrete `BuildLayout` on the abstract class and expose a `protected abstract void BuildHeader(ref DynamicGumpBuilder builder)` hook for subclasses (replacing the old `Design()` override). This mirrors the abstract-base treatment used for the ML quest base in the quest-gump migration PR.
**Concrete subclasses migrated alongside the abstract bases:**
- `GuildListGump` subclasses: `GuildAcceptWarGump`, `GuildDeclarePeaceGump`, `GuildDeclareWarGump`, `GuildRejectWarGump`, `GuildRescindDeclarationGump`
- `GuildMobileListGump` subclasses: `DeclareFealtyGump`, `GrantGuildTitleGump`, `GuildAdminCandidatesGump`, `GuildCandidatesGump`, `GuildDismissGump`, `GuildRosterGump`
**Cliloc rule:** Every gump bakes per-instance dynamic content (guild names, member names, war declarations, candidate lists), which would defeat `StaticGump<T>` caching. Per the cliloc rule, all are `DynamicGump`.
**External callers updated:** the prompt files (`GuildAbbrvPrompt`, `GuildCharterPrompt`, `GuildDeclareWarPrompt`, `GuildNamePrompt`, `GuildTitlePrompt`, `GuildWebsitePrompt`), `RecruitTarget`, the `Guildstone` item, and the New Guild System `GuildInfoGump`'s Order/Chaos handler all now go through static `DisplayTo` entry points instead of `new XGump(...)`.
## Summary
Removes per-call heap allocations from `Container`'s consume / find / group hot paths and from `BaseCreature.OnDeath`'s fame/karma tracking. The headline wins: kill the `List<List<Item>>` + `Item[][]` + `int[]` grouping bridges in `ConsumeTotal*` / `ConsumeTotalGrouped*` / `GetBestGroupAmount*`, and kill the per-call `Predicate<Item>` allocations in `FindItemsByType(Type)` / `FindItemsByType(Type[])`.
### `Container.cs`
- `ConsumeTotal`, `ConsumeTotalGrouped`, `GetBestGroupAmount` now share four streaming helpers (`HasAmount`, `TryFindGroupMeetingAmount`, `BestGroupTotal`, `ConsumeSlice`) backed by `PooledRefList` instead of allocating per-group lists and jagged arrays. Two-phase validate-then-consume pattern preserved — all-or-nothing semantics for spell reagents, vendor pay, and crafting still hold.
- `(Type)` / `(Type[])` / `(Type[][])` overload trios collapsed to single `ReadOnlySpan<Type>` + `ReadOnlySpan<int>` implementations. Implicit `T[] → ReadOnlySpan<T>` conversion means UOContent callers compile unchanged.
- Unused overloads deleted: `ConsumeTotalGrouped(Type)`, `ConsumeTotalGrouped(Type[][])`, `GetBestGroupAmount(Type)`, `GetBestGroupAmount(Type[][])`, plus the never-called `TryDropItems` hook and its private `ItemStackEntry` struct.
- Fixes a `PooledRefList` leak in `GetBestGroupAmount(Type[], …)` (missing `using`).
- `m_ContainerData` / `m_Items` / `m_TotalGold` / `m_TotalItems` / `m_TotalWeight` / `ContainerData.m_Table` / `ContainerData.logger` renamed to the underscored convention. `m_Items` cross-file rename for the Container-side references in `Item.cs`; `Item.CompactInfo.m_Items` deliberately left alone (separate effort).
- `CheckHold` parent walk simplified; trivial dispatch methods (`CheckHold` overloads, `OnItemAdded`, `OnItemRemoved`, `OnStackAttempt`) get `[MethodImpl(AggressiveInlining)]`; `Destroy` and `DisplayTo` cache `Items` outside the loop; dead comments removed.
### `Item.Enumerable.cs`
- `FindItemsByType(Type)` previously allocated a `Predicate<Item>` per call (method-group conversion). `FindItemsByType(Type[])` allocated a closure capturing `types`. Both now construct the enumerator with a `Type` / `ReadOnlySpan<Type>` field directly, no delegate.
- `FindItemsByTypeEnumerator<T>` gains two constructors plus a `Matches(T)` helper that picks the right filter inline. Constructor chaining via a private 2-arg seed constructor incidentally fixes a pre-existing bug where `PooledRefQueue` was always rented at capacity 0 because `_recurse` hadn't been assigned yet.
- `(Type[])` overload of `FindItemsByType` becomes `(ReadOnlySpan<Type>)`.
- `EnumerateItemsByType(Type)` / `EnumerateItemsByType(ReadOnlySpan<Type>)` / `ListItemsByType(Type)` / `ListItemsByType(ReadOnlySpan<Type>)` simplified to delegate to the new alloc-free overloads instead of filtering manually.
### `Utility.cs`
- `InTypeList<T>(this T, Type[])` and `InTypeList(this Type, Type[])` switched to `ReadOnlySpan<Type>`.
### `BaseCreature.cs`
- `OnDeath` per-death `List<Mobile>` / `List<int>` / `List<int>` for fame/karma tracking switched to `PooledRefList`.
## Summary
Replaces the basic `publish.cmd`/`publish.sh` scripts with an interactive **BuildTool** — a C# console app using [Spectre.Console](https://spectreconsole.net/) that guides users through publishing, prerequisite checking, and cross-compilation.
### Why
The community found the existing publish scripts unhelpful for newcomers. They worked but didn't walk users through the process, didn't check prerequisites, and provided no feedback when things went wrong.
### What's New
**Interactive BuildTool** (`Projects/BuildTool/`)
- NativeAOT-compiled C# console app with true-color ASCII logo and ModernUO brand gold/silver palette
- Guided publish wizard with step-by-step back navigation (Ctrl+C or menu "Back" to go to previous step)
- Prerequisite checking: .NET SDK version, VC++ Redistributable (Windows), native libraries (Linux/macOS)
- .NET SDK auto-install offer via Microsoft's official install scripts
- Platform detection: Windows 10 vs 11 (build number), macOS codenames, Linux distro + kernel version
- Cross-compilation support: skips native library checks, shows target prerequisites after build
- Non-interactive mode for CI: `--config Release --skip-prereqs`
- Backward-compatible positional args: `publish.cmd release win x64` still works
**Shell Wrappers** (`publish.cmd`, `publish.ps1`, `publish.sh`)
- Try native BuildTool binary first (downloaded from GitHub Releases)
- Fall back to `dotnet run --project Projects/BuildTool` if unavailable
- SDK bootstrapping: offer to install .NET if not found
**CI/CD Updates**
- Build/test workflows target `Projects/Application/Application.csproj` instead of the solution (excludes BuildTool and test projects from publish)
- New `build-tool-release.yml` workflow builds NativeAOT binaries for win-x64, win-arm64, osx-arm64, linux-x64, linux-arm64
- Minimum SDK bumped to 10.0.201 (required for Serialization Generator 2.14.3 / Roslyn 5.3.0)
**Other Changes**
- Solution converted from `.sln` to `.slnx`
- Updated README with interactive mode instructions and deployment guidance
## Screenshots
<img width="320" height="378" alt="image" src="https://github.com/user-attachments/assets/83c057c5-3992-4dbd-99fa-0e3c24ef6428" />
<img width="749" height="554" alt="image" src="https://github.com/user-attachments/assets/e4ee4d6f-71d4-47f9-86b6-8fd1ca3c3e7a" />
## Summary
- **Add a self-referencing `InterpolationHandler` to `ValueStringBuilder`** that writes directly into the builder's buffer — zero intermediate allocation, works with `stackalloc`-backed builders
- **Replace all `System.Text.StringBuilder` usage** across the codebase with `ValueStringBuilder`
- **Convert `ValueStringBuilder.Create()` to `stackalloc`** at 10 sites where output length is provably bounded
- **Convert manual `Dispose()` to `using var`** where possible, and hoist loop-scoped builders outside loops with `Reset()`
- **Convert verbose `Append()` chains to `Append($"...")`** interpolation for readability
- **Add comprehensive documentation** for string handling patterns
## InterpolationHandler Design
`ValueStringBuilder` is a `ref struct`, which creates challenges for C#'s interpolated string handler pattern:
- **`ref` fields to ref structs are not allowed** (CS9050)
- **`[InterpolatedStringHandlerArgument("")]` passes struct receivers by value**, not by ref
- **`ISelfInterpolatedStringHandler` requires boxing** ref structs into interface fields
**Solution: Copy-and-reconcile pattern.** The handler receives a value copy of the builder. The copy shares the same underlying `char` buffer (`Span` points to the same `stackalloc`/pooled memory), so writes go to the original buffer. `Append()` reconciles by `this = handler._builder`, updating `_length` and any buffer references changed by `Grow()`.
This is safe because:
- The game loop is single-threaded — no concurrent access between handler construction and reconciliation
- If `Grow()` occurs in the copy, the original's stale buffer isn't accessed until `Append()` replaces it
- `Dispose()` correctly returns the reconciled buffer to the pool
## Changes by Category
### ValueStringBuilder (`Projects/Server/Buffers/ValueStringBuilder.cs`)
- Added nested `InterpolationHandler` ref struct with copy-and-reconcile pattern
- Added `Append([InterpolatedStringHandlerArgument("")] scoped ref InterpolationHandler)` method
- Removed `RawInterpolatedStringHandler` overloads (new handler replaces them)
- All `AppendFormatted` overloads delegate to existing `Append` methods (no code duplication)
- Alignment support via direct private field access (nested type privilege)
### StringBuilder → ValueStringBuilder (15 files)
Replaced all `new StringBuilder()` with `ValueStringBuilder.Create()` or `stackalloc`:
- ConPVP games: KingOfTheHill, DoubleDom, CTF, BombingRun, TourneyMatch
- ConPVP infrastructure: Tournament, Participant, TourneyParticipant
- ConPVP gumps: ArenaGump, TournamentBracketGump, AcceptTeamGump, ConfirmSignupGump
- Commands: Handlers, Logging, Add
- Other: TownCrier, SpeechLogGump, TestCenter
Key patterns:
- `sb = new StringBuilder()` reassignment → `sb.Reset()`
- `sb.AppendFormat("{0:N0}", value)` → `sb.Append($"{value:N0}")`
- `sb.Append(x).Append(y)` chains → separate statements (VSB returns void)
### Create() → stackalloc (10 files)
Converted heap-allocated builders to stackalloc where output is bounded:
- ClientVersion (32), MapSelection (160), HouseRaffleStone (48)
- HolySense (96), UnholySense (96), ClientVerification (192)
- AcceptTeamGump (64), ConfirmSignupGump (64)
- BaseWeapon (160), BaseArmor (128)
### Loop optimizations (2 files)
Hoisted `ValueStringBuilder` creation outside loops with `Reset()` per iteration:
- TourneyMatch.cs: `using var` inside for loop → stackalloc before loop
- ArenaGump.cs: `Create()` + `Dispose()` per iteration → stackalloc before loop
### Append chain → interpolation (5 files)
Converted multi-line `Append()` chains to `Append($"...")`:
- BountyMessage.cs: title switch (6 cases), paragraph (15→1 Append), description lines, closing
- AcceptTeamGump, ConfirmSignupGump, TournamentBracketGump: tournament type strings
- AdminGump: comment/tag formatting in loops
### Documentation
- `dev-docs/string-handling.md`: Full reference — construction, interpolation, disposal, decision guide
- `dev-docs/claude-skills/modernuo-string-handling.md`: Claude skill with quick reference
- `CLAUDE.md`: Added rule 17 (no StringBuilder), dev-docs table entry, skills table entry
- `dev-docs/code-standards.md`: Updated memory management section
## Test Plan
- [x] `dotnet build` — 0 errors, 0 warnings
- [x] `dotnet test` — 940/940 tests pass
- [x] 28 ValueStringBuilder tests covering all reconciliation scenarios:
- Stackalloc no-grow, stackalloc with grow (→pool transition)
- Heap no-grow, heap with grow, heap double grow
- Pre-existing content with and without grow
- Sequential multiple `Append($"...")` calls
- Mixed plain + interpolated Append
- Empty interpolation, literal-only, format specifiers
- Null string holes, ISpanFormattable types
- Dispose after stackalloc→pool grow
## Summary
- Refactors the poison system to separate `Index` (globally unique ID) from `Level` (tier within a family), enabling multiple poison families (Standard, Darkglow, Parasitic) to coexist without collisions
- Implements Darkglow and Parasitic poison special effects from Mondain's Legacy: Darkglow boosts damage by 10% when attacker is ranged, Parasitic heals the attacker for damage dealt in melee range
- Fixes several bugs: `Register()` crashing on duplicate `Level` values across families, `IncreaseLevel()` crossing family boundaries, `InfectiousStrike` and `NinjaWeapons` stripping poison family via level-based lookups, and `ArchCure`/`CleansingWinds` using raw `Level + 1` instead of `IncreaseLevel()`
## Changes
**`Projects/Server/Poison.cs`** — Adds `PoisonFamily` enum and abstract `Family` property. Adds `Index` as unique identifier. Fixes `Register()` to check `Index` uniqueness (not `Level`) and validate the new poison's name (not the existing one's). Fixes `IncreaseLevel()` to use `Index + 1`, naturally respecting family boundaries via Index gaps. Replaces linear name lookup with `Dictionary`-based `PoisonsByName`.
**`Projects/UOContent/Misc/Poison.cs`** — Adds `family` parameter to `PoisonImpl`. Implements Darkglow effect (10% damage boost when `From` >1 tile, cliloc 1072850) and Parasitic effect (heals `From` for damage dealt within 1 tile, cliloc 1060203) in `PoisonTimer.OnTick()`. Renames `m_` fields to `_` convention.
**`Projects/UOContent/Misc/PoisonKinds.cs`** — New file. Moves poison registration out of `PoisonImpl` into `PoisonKinds.Configure()`. Adds `PoisonFamily` to Darkglow/Parasitic registrations. Provides extension properties (`Lesser`, `Deadly`, `LesserDarkglow`, etc.), `GetPoison(int level)` (standard-only), `GetPoisonByFamilyAndLevel()`, and `IsDarkglow`/`IsParasitic` instance helpers.
**`Projects/UOContent/Items/Weapons/Abilities/InfectiousStrike.cs`** — Family-aware poison scaling: Darkglow caps at Deadly (Poisoning/33.3), Parasitic caps at Lethal (Poisoning/25), Standard unchanged. Level bump uses `IncreaseLevel()` with family boundary check.
**`Projects/UOContent/Items/Skill Items/Ninjitsu/NinjaWeapons.cs`** — EvilOmen level bump uses `Poison.IncreaseLevel()` instead of `Poison.GetPoison(Level + 1)`.
**`Projects/UOContent/Spells/Fourth/ArchCure.cs`** and **`CleansingWindsSpell.cs`** — Replace `poison.Level + 1` with `Poison.IncreaseLevel(poison).Level` for family-safe cure chance calculation.
**`Projects/Server/Serialization/SerializationExtensions.cs`** — Serializes/deserializes `Index` instead of `Level`.
**`DarkglowPotion.cs`** / **`ParasiticPotion.cs`** — Point to actual Darkglow/Parasitic poisons instead of placeholder `Greater`.
**`PotionKeg.cs`** / **`BasePotion.cs`** — Adds Darkglow, Parasitic, Invisibility, and FlintsPungentBrew to `PotionEffect` enum and keg label support.
## Test plan
- [ ] `dotnet build` compiles cleanly (verified, 0 warnings 0 errors)
- [ ] Verify `PoisonKinds.Configure()` registers all poisons without throwing (Register bug fix)
- [ ] Standard poison behavior unchanged — PoisonField, PoisonSpell, SerpentArrow, SavageShaman, TrappableContainer all use `GetPoison(int level)` which now correctly filters to Standard family
- [ ] Darkglow: poison tick deals +10% damage when attacker is >1 tile away, sends "Darkglow poison increases your damage!" message
- [ ] Parasitic: poison tick heals attacker for damage dealt when within 1 tile, sends heal message
- [ ] InfectiousStrike preserves poison family and respects family-specific skill scaling
- [ ] EvilOmen + NinjaWeapons level bump stays within poison family
- [ ] ArchCure/CleansingWinds cure chance calculations work correctly across all poison families
- [ ] Serialization round-trips correctly using Index
## Summary
- **Timer-aware idle sleep**: Exposes `Timer.MillisecondsUntilNextTick()` to calculate remaining ms until the next timer wheel tick (0–8ms). The game loop sleeps for that duration minus a 1ms safety margin, instead of spinning at 100% CPU.
- **I/O completion wakeup**: Replaces `Thread.Sleep` with `NetState.WaitForCompletion()`, which uses platform-native completion notification (RIO `RIONotify` on Windows, `eventfd` on Linux, `kevent` timeout on macOS) to wake immediately when network data arrives during sleep.
- **Always-on**: Removes the debug-only `core.enableIdleCPU` config gate. The sleep is self-regulating — under load, `MillisecondsUntilNextTick` returns 0 so no sleep occurs (zero overhead). On idle, CPU drops from ~100% to ~1%.
- **CPS calculation cleanup**: Replaces the 128-element ring buffer with an EMA (exponential moving average) for `CyclesPerSecond`/`AverageCPS` — fewer allocations, no LINQ `.Average()` call each sample.
- **IORingGroup 1.0.6**: Adds `WaitForCompletion(int timeoutMs)` to the `IIORingGroup` interface with platform implementations:
- **Windows**: `RIONotify` arms the CQ event, `WaitForSingleObject` with timeout
- **Linux**: `eventfd` registered with io_uring, `poll()` with timeout
- **macOS**: `kevent()` with timeout
## Test plan
- [ ] Build succeeds on all platforms (`dotnet build`)
- [ ] Empty server: verify CPU usage drops from ~100% to ~1% idle
- [ ] Loaded server: verify no added latency — `MillisecondsUntilNextTick` returns 0 when timers are firing, sleep is skipped
- [ ] Connect a client during idle — verify connection accepted within one timer tick (~8ms)
- [ ] Verify `[admin` gump shows reasonable CPS values (EMA convergence)
## Summary
Server-side movement throttle that prevents speed hacking while accurately identifying cheaters with detection of lagging connections.
**Key features:**
- Credit buffer (200ms) absorbs timing jitter from legitimate players
- Movement queue handles larger bursts, draining at proper game-tick intervals
- RTT measurement distinguishes network lag from speed hacks
- Queue depth detection catches ACK-throttled speed hacks (going straight)
## How It Works
**Throttle** (prevention): Movements arriving too early either consume credit or get queued. The queue drains at
correct intervals, so speed hackers can't move faster regardless of what they send.
**Detection** (identification): Combines multiple signals to identify cheaters:
| Signal | What it catches |
|--------|-----------------|
| Queue depth ≥4 sustained | ACK-throttled speed hacks (client limits unacked moves to 5) |
| Movement rate >1.05x | Direction-change speed hacks where timing is visible |
| Stable RTT + high queue | Eliminates false positives from laggy players |
**RTT-Aware Logic:**
- Probes only sent to players actively moving (event-driven, not global loop)
- Stable low-latency + problems = suspicious
- Unstable/high-latency + problems = probably just lag, throttle handles it
## Configuration
```json
{
"movementThrottle.maxCredit": 200,
"movementThrottle.softQueueLimit": 6,
"movementThrottle.hardQueueLimit": 10,
"movementThrottle.debugLogging": false
}
```
## Summary
- Adds `public virtual bool Murderer => Kills >= 5` property to `Mobile`, replacing ~30 scattered `Kills >= 5` / `Kills < 5` magic-number checks across the codebase
- `BaseCreature` overrides `Murderer` to also return `true` when `AlwaysMurderer` is set
- Updates `Corpse` serialization to v15, storing `_murderer` as a `bool` field (migrated from `int Kills >= 5` in earlier versions)
### Summary
Updates all calls to container.EnumerateItems() to properly dispose of the underlying PooledRefQueue so that we are properly recycling pooled arrays.
### Summary
- Bump IORingGroup 1.0.0 → 1.0.1 — fixes a disconnect handling bug in the native ring layer
- Fix ghost NetStates — Dispose() set _running = false before checking it, so the "force immediate disconnect" path
was dead code. Capture wasRunning before clearing it, add [Obsolete] guard, and route internal callers through
DisposeInternal()
- Fix unauthenticated socket cleanup — graceful disconnect on unauthed connections could get stuck with pending sends;
now force-immediate after Disconnect() if DisconnectPending is already set
- Replace ConcurrentQueue<NetState> _disposed with Queue<NetState> — server is single-threaded; moved the field into
the Network partial class where it's consumed
- Move ConnectingSocketIdleLimit into the Network partial class alongside DisconnectUnattachedSockets
- Reset activity timer on receive, not just send — receiving data directly proves liveness instead of relying on the
ping→pong→send round-trip to reset the timer
- Move CheckAllAlive from Timer into Slice — the timer fired before I/O completions were processed, so after server
stalls (world saves), buffered client pings hadn't reset timestamps yet, causing false disconnects. Now runs at the
end of Slice() after all recv completions are handled
- Lower inactivity timeout 90s → 30s, check interval 90s → 5s — clients ping every ~1s, so 30s of silence is ~30
missed pings; worst-case detection drops from ~180s to ~35s
- Simplify CheckAlive — early-return when socket is null or alive; force-kill stuck DisconnectPending sockets
immediately instead of calling Disconnect() again
- Remove unused imports from GameEncryption.cs
### Summary
Changes component verification so the order is now housing.bin, then txt files in client, then txt files in Data/Components folder on the server.
