RedstoneRegions

# RedstoneRegions Per-chunk redstone engine switching for Folia. Mark a chunk and its wire ticks 2-14× faster; everything else stays vanilla. If you've run a big server you know the tradeoff. You can set `redstone-implementation: alternate-current` in `paper-world.yml` and get a huge speedup globally. Then some player's piston BUD farm from 2019 quietly stops working and you spend a week figuring out why. Or you keep everything vanilla and watch a 64×64 dust floor eat your tick budget. It's an all-or-nothing switch, and neither "all" nor "nothing" is what you actually want. So this makes it per-chunk instead: ``` /redstone-region set alternate-current ← this chunk only /redstone-region fill 8 alternate-current ← 17×17 chunks around you /redstone-region selection eigencraft ← your WorldEdit selection /redstone-region undo ← oh wait, no ``` The choice persists (stored in chunk PDC), survives restarts, and hot-swaps live, no restart or chunk reload needed. ## The four engines | Mode | Speed | Notes | |---|---|---| | vanilla | 1× | the default. Everything behaves like normal Minecraft. | | alternate-current | 2-14× | Space Walker's algorithm. Two known edge cases, see below. | | eigencraft | 3-5× | almost no edge cases. Good for piston/observer machinery. | | disabled | frozen | wire never updates. For archived builds you want inert. | ## Numbers My benchmark is a 32×32 dust grid, toggled from one lever: | Run | Vanilla | AC | | |---|---|---|---| | Cold | 234 ms | 22 ms | 10.6× | | Warm JIT | 41 ms | 14 ms | 2.9× | | Pre-warmed | 71 ms | 5 ms | 14.2× | The honest takeaway: the "14×" happens when vanilla is at its worst, steady-state is more like 3×. Either is a lot when the vanilla number blows a 50 ms tick. At 64×64 chunks of dust, vanilla overshoots a tick by 6×; AC stays under 2. Cost when you're *not* using it: every wire update passes through a per-chunk dispatcher, which is a StampedLock optimistic read plus a switch, about 50 ns. If even that bothers you there's `timing.mode: sample` (~5 ns at sample-rate 10) or `off` (nothing at all). ## What's in the box The core is the per-chunk switching. Around that, mostly things I ended up needing while running it: - WorldEdit selection support, so you can flip a whole machine room from `//pos1 //pos2` - a BlueMap overlay that draws colored rectangles over non-vanilla chunks, which turned out to be the fastest way to spot "wait, why is *that* chunk on AC" - an optional auto-scanner that flips chunks to AC when their vanilla redstone time crosses a threshold - `` signs so trusted players can flip their own chunks without bugging staff (permission-gated, radius-capped) - `/redstone-region profile` for a live per-chunk readout against the 50 ms budget - `/redstone-region why x y z`, which explains a wire's power level by walking its six neighbors. Sounds silly, saves so much time debugging - `/redstone-region undo` for the last batch, whatever caused it (set, fill, selection, sign, auto-scanner) - an audit log (JSONL, rolled daily, actor + UUID + reason on every flip) and an optional Discord webhook, because on a real server people *will* ask who touched their chunk - PlaceholderAPI placeholders, click-to-teleport chunk coordinates in chat, hot config reload - English and French included; drop a `lang/<code>.yml` for anything else ## Install Jar in `plugins/`, restart, stand somewhere, `/redstone-region set alternate-current`. That's the whole thing. Requirements: Folia 1.21.11 build 6 or later (Luminol and other forks work), Java 21. BlueMap 5.16+, PlaceholderAPI 2.11.7+ and WorldEdit 7.3.19+ are all optional. For WorldEdit, prefer a Folia-patched build. ## Does it actually behave like vanilla? This was the part I was paranoid about, so there's an in-server test harness. Current results, 14/14: - byte-for-byte parity with vanilla across 8 contraptions over 60+ ticks each: dust line, 16×16 grid, 4-tick repeater clock, AND gate, comparator subtraction, torch ladder, torch inverter, dust zigzag - 596 toggles in a 30-second stress run, zero exceptions - 780 + 780 toggles running in two different Folia regions *at the same time*, zero races, zero thread-check failures (this is the case Paper's bundled AC can't currently pass under Folia) - 655 dispatches into the AC engine confirmed by counter, so the routing isn't silently falling back ## How it works, short version As of 1.21.2 Mojang exposes a `RedstoneWireBlock.evaluator` field. At boot we swap it for a dispatcher that checks the chunk's flag and routes the update to the right engine. The AC engine is a port of Space Walker's algorithm, modified to use per-thread WireHandlers. The bundled AC in Paper shares one handler across everything, which is a latent race once Folia runs regions in parallel. Longer version with diagrams: (https://github.com/uncaney/folia-redstone-region/blob/main/docs/ARCHITECTURE.md). ## The edge cases, honestly