## 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
# Bounty Boards
<img width="717" height="382" alt="image" src="https://github.com/user-attachments/assets/455e5206-47d8-4449-805c-19b143d059e5" />
<img width="918" height="637" alt="image" src="https://github.com/user-attachments/assets/e78e1ca2-62b8-4abf-8f69-21438bb1b759" />
<img width="340" height="296" alt="image" src="https://github.com/user-attachments/assets/fd17d7e6-8c53-47df-ac58-a89ea3ef665e" />
## Setup
* Setup as part of decorate when bounty system is enabled
* Several bounty board locations with a WarriorGuard spawner in front of the board. Guard spawns and idles around 5 range.
## Tests
### ReportBountyMurdererGump
* Follows same behaviour as ReportMurdererGump
* Extracted common logic
* Didn't use staticgump due to several dynamic parts including input
* Optional bounty with validation >0 and <bankbox.total
* Murder report is honored either way
### Bounty boards
* Open bounty board with many bounties, no bounties
* Keep a bounty board open, invalidate a bounty by turning in the head, then try to click on the post of the now invalid post. As expected: does nothing
* Bounty messages use the last murder time as their post date and expire in 14 days
* Bounty boards/messages are not reliant on serialization; they use serialized fields from MurderContext to build messages when clicked.
* Bounty messages use synthetic serials so they do not have to persist bounty messages as items. They are constructed and sent as raw packets when needed.
* Players only appear on the bounty board if they are a murderer (though a non-murderer can technically still have a bounty if they decayed kills)
* Tested skin/hair color descriptions vs a dozen spot checks
### Head turn in behaviour
* Guard accepts head
* Bounty -> gives bounty
* No bounty -> generic response
* Expired head (24h) -> generic response
NOTE: CUO "latest" has a bug with bounty/bulletinmessages that causes overflow outside of the container. It has nothing to do with this PR. It is fixed here in CUO https://github.com/ClassicUO/ClassicUO/pull/1871
# Murderer title
Bounty system and "murderer" title eliminated in [pub16](https://uo.com/wiki/ultima-online-wiki/technical/previous-publishes/2002-2/publish-16-part-2-5-23rd-july/). So UO:LBR and before had bounties and murderer title.
# Pre-T2A caveat
There were differences in pre-T2A, but this cannot be currently implemented because we do not have any pre-T2A systems in general, so at least for now, behavior is consistent with later eras. Pre-T2A was a whole other ballgame, but the bounty system still worked similarly.
## Summary
Implements T2A-accurate mechanics for the three defensive spells based on UO98 demo scripts. Pre-UOR (`!Core.UOR`) triggers the new behavior; UOR and AOS paths are unchanged.
- **Reactive Armor**: percentage-based melee damage reflection (10-35% based on target Magery), targeted, timed (25-75s). Guards exempt, ranged attacks beyond 1 tile unaffected. Reflected damage is sourceless.
- **Protection**: temporary AC bonus (casterMagery/10, 1-10 AR) via VirtualArmorMod, targeted, timed (12-120s). Shared table with Arch Protection — only one protection buff per mobile.
- **Magic Reflect**: single-use spell reflection using MagicDamageAbsorb as a flag. No timer, no DefensiveSpell lock. Consumed on first reflected spell.
- **Arch Protection**: T2A path applies Protection via shared table with area sound (0x1F7 vs 0x1ED).
- No DefensiveSpell mutual exclusion for T2A — all three spells operate independently.
## Test plan
- [x] Set expansion to T2A
- [x] Cast Reactive Armor on self → verify particles (0x376A) and sound (0x1F2)
- [x] Get hit in melee → verify attacker takes reflected damage with spark effect and sound
- [x] Get hit by ranged weapon from > 1 tile → verify no reflection
- [x] Wait for RA to expire → verify effect ends silently
- [x] Cast RA on target that already has it → verify "This spell is already in effect"
- [x] Cast Protection on another player → verify particles (0x375A) and sound (0x1ED)
- [x] Check target's AR → verify it increased by casterMagery/10
- [x] Wait for Protection to expire → verify AR returns to normal
- [x] Cast Protection on self, then cast Protection on another player → verify both succeed
- [x] Cast Arch Protection on ground near allies → verify each gets AR bonus with sound 0x1F7
- [x] Cast Arch Protection near a target already protected → verify that target is skipped
- [x] Cast Magic Reflect on self → verify particles (0x375A) and sound (0x1E9)
- [x] Have an enemy cast a harmful spell at you → verify spell reflects back, effect consumed
- [x] Cast Magic Reflect again → verify it can be recast after consumption
- [x] Cast Magic Reflect when already active → verify "This spell is already in effect"
- [x] Verify all three spells can be active simultaneously on the same mobile
- [x] Switch expansion to UOR → verify existing UOR behavior unchanged
- [x] Switch expansion to AOS → verify existing AOS behavior unchanged
## Summary
- Adds `Mobile.Murderer` virtual property and consolidates kill-threshold checks across the codebase
- Tracks ping-pong count: how many times a player crosses the 5-kill murderer threshold (T2A/UOR/UOTD only, disabled on LBR+)
- Adds `[CommandProperty]` to view a player's ping-pong count via the admin panel
- After enough ping-pongs, player is permanently flagged as a murderer regardless of kill count
- Accounts for perma-red players with low kills in murderer status transition notifications
- Implements era-appropriate "I must consider my sins" speech responses:
- **T2A**: contextual cliloc flavor text (502122–502126)
- **UOR–AOS**: raw short/long-term murder counts + ping-pong count if applicable
- **SE+**: localized stats message (1114370)
- Refactors kill-report logic out of `Keywords.cs` into `PlayerMurderSystem.ReportKillsToSelf`
## Testing
- [x] Thoroughly tested and self reviewed
- [x] Test T2A "I must consider my sins" behaviour over all scenarios.
- [x] Test UOR "I must consider my sins" behaviour over all scenarios.
- [x] Test that LBR does not have ping pongs enabled (I must consider my sins)
- [x] Test serialization cross over from v0 -> v1 increments 1 ping pong if player is already red.
## Notes
* Manually setting kills to 5 does not trigger a ping pong, it must go through the actual murder system. This includes if the kills were manually set to 5 and then migrated (as manually setting kills to 5 never adds the player into the murder system - it only happens via ReportMurderer). This is arguably a bug in the existing system, but one that currently only ever happens via staff interaction.
* Thieves guild SuspendOnMurder specifically checks for kills > 0. This means a person with 0 shorts but 5 ping pongs (flagged as murderer) can steal. This may be accurate, as according to a forum post this is how it works on UOSA which is the T2A gold standard.
* This doesn't implement Pre-T2A behaviour which should be that "I must consider my sins" does nothing at all. The reason I didn't implement it for Pre-T2A is then it 100% have to sit behind a feature flag. I don't mind adding it as a feature flag, just let me know.
## 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.
Fix [add command failing with ambiguous type names + refactor for performance
### Problem
[add blight would fail with "No type with that name was found" because multiple types contain "blight" (e.g., Server.Items.Blight, Server.Ethics.Evil.Blight, Server.Items.BlightGrippedLongbow, Server.Items.QuiverOfBlight). The old code only succeeded when exactly one type matched the search regardless of constructability and inheriting Mobi les/Items.
### Solution
Exact match takes priority: If a type's name exactly equals the search string (case-insensitive), use it directly. Otherwise, show the AddGump with all partial matches.
- [add blight → Creates Blight (exact name match)
- [add bligh → Shows gump with Blight, BlightGrippedLongbow, etc.
### Refactoring
- CommandEventArgs context: Added GetContext<T>/SetContext<T> to pass resolved type through the command chain without method signature changes
- Removed TrySetupTarget duplication: Validation now happens only in ValidateArgs, eliminating redundant code paths
- Split type matching:
- ExactMatch(string) → Returns Type for exact name match (used by [add)
- MatchEmptyCtor(string) → Returns ConstructorInfo[] for gump display (empty-callable constructors only)
### Memory & Performance Improvements
| Optimization | Benefit |
|-------------------------------|----------------------------------------------------------------------------------------------|
| _mobileItemTypes cache | Filters Mobile/Item types once per assembly, reused on all subsequent searches |
| ReadOnlySpan<string> for args | Avoids string[] heap allocations when slicing arguments |
| ValueStringBuilder | Stack-allocated string building, avoids StringBuilder heap allocation |
| Single type resolution | Type resolved once in ValidateArgs, passed via context to Execute (was resolved 2-3x before) |
### Summary
- Create BitMask256 struct with scalar operations (benchmarks showed AVX2 vectorization provides no benefit for this size)
- Refactor Map.cs to use BitMask256 for full Z range support (-128 to 127)
- Remove SectorSpawnCache struct, use BitMask256 directly in manager
- Update tests to use BitMask256 directly
- Remove unused test assertions for old 64-bit behavior
### Summary
- Adds CanSpawnMobile(x, y, minZ, maxZ, canSwim, cantWalk, out spawnZ) overload for finding spawn surfaces within a Z range
- Adds CanSpawnItem(x, y, minZ, maxZ, out spawnZ) for item spawning with Surface+Impassable support (tables, furniture)
- Uses bitmask optimization inspired by Item.DropToWorld's m_OpenSlots pattern for O(1) surface/blocker checks
- HomeRange spawners now use surface detection to set proper Z bounds
### Key Changes
Map.cs:
- CanSpawnMobile with Z-range finds lowest valid surface for mobiles
- CanSpawnItem with Z-range finds lowest valid surface for items (including tables)
- CanFitItem for point-check item placement on Surface+Impassable tiles
- Bitmask approach eliminates nested loops and stackalloc arrays
Spawners:
- Simplified GetSpawnPosition using new Z-range methods
- HomeRange setter detects surface below spawner for proper Z bounds
- Consistent handling for mobiles and items
### Bug Fixes
- Water tiles (Impassable | Wet) no longer block swimming mobs
- Items can now spawn on tables/furniture (Surface+Impassable)
### Test Plan
- Run dotnet test - 631 tests pass
- Manual testing: multi-story spawning, water mobs, item spawning on tables
- Verify HomeRange spawner movement shifts bounds correctly
### Summary
This PR transitions the spawner system from a simple radius-based model to a flexible 3D boundary system.
### Core Changes
* **Replaced `HomeRange` with `SpawnBounds`**: Spawners now use a `Rectangle3D` to define spawn areas instead of a circular integer range.
* **Backward Compatibility**:
* The `HomeRange` property remains as a helper that generates square `SpawnBounds` centered on the spawner.
* Included a migration path (v10 to v11) that automatically converts old range data into new bounds during deserialization.
* **Dynamic Bounds Shifting**: If a spawner is moved, its `SpawnBounds` will automatically shift with it, provided the bounds are currently configured as a centered square.
* **New Spawn Logic**: Added `SpawnLocationIsHome` toggle. If enabled, spawned mobiles treat their exact spawn coordinates as their "Home" rather than the spawner's location.
### Implementation Details
* **Interface Updates**: Updated `ISpawner` to include `WalkingRange`, `SpawnBounds`, and `IsInSpawnBounds()`.
* **UI Enhancements**: The Spawner Controller Gump now displays "Custom" for complex bounds and allows copying of the new boundary properties between spawners.
* **Refactored Constructors**: Streamlined `BaseSpawner`, `ProximitySpawner`, and `RegionSpawner` constructors to support the new data types.
> [!IMPORTANT]
> **Developer Note**
> THIS IS A BREAKING CHANGE TO THE NEW API GUMP.
> Please give us feedback in [discord ](https://muo.gg/discord) if you have issues, need help, or have ideas for a better API change!
### Summary
* Adds support for size/style to dynamic/static builder.
* Drastically simplifies the dynamic/static builder api for AddHtml.
* Cleans up some legacy gump files.
* Initial plan
* Add SerializableFieldDefault attributes for LeftSeeds and LeftResources
This fixes the serialization bug where _leftSeeds and _leftResources were initialized to 8 in the constructor but didn't serialize when their value was 0. Upon deserialization, the constructor would run again and reset these values back to 8.
The SerializableFieldDefault attributes tell the serialization system that the default value is 8, so it will properly serialize 0 values and maintain the correct state across server restarts.
Co-authored-by: kamronbatman <3953314+kamronbatman@users.noreply.github.com>
* Update ShouldSerialize methods to check against default value
Changed ShouldSerializeLeftSeeds() and ShouldSerializeLeftResources() to check if the value is != 8 (the default) instead of != 0. This ensures that only non-default values are serialized, following the same pattern used in BaseWeapon.cs and other classes with SerializableFieldDefault attributes.
Co-authored-by: kamronbatman <3953314+kamronbatman@users.noreply.github.com>
---------
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: kamronbatman <3953314+kamronbatman@users.noreply.github.com>
### Summary
* Moves BOBGump to DynamicGump.
* BOBGump no longer creates a whole new gump context object on every send.
* Moves BODBuyGump to StaticGump.
### Summary
* Replaces the node chain with a PriorityQueue.
* Performance difference is up to 3x faster.
### Benchmarks
```cs
| Method | Mean | Error | StdDev | Gen0 | Allocated |
|-------------------- |---------:|----------:|----------:|-------:|----------:|
| FastAStar_PQueue | 2.112 us | 0.0186 us | 0.0165 us | 0.0038 | 64 B |
| FastAStar_NodeChain | 6.430 us | 0.0800 us | 0.1807 us | - | 64 B |
```
### Video
https://github.com/user-attachments/assets/3edd2524-5146-4775-be45-3516f0b01c27
### Summary
* Refactors AI so it is easier to read and maintain
* Fixes NPC speed issues
* Fixes pet sector AI issue that was causing stuttering
* Fixes direction snapping for Melee/Mage AI
* Refactors pet orders
* Refactors speech commands
* Removes scale speed by dex for HS+ (it was a stupid feature anyways)
