- a size-less `<Model>` pane's rect is its file's box in layout units: the reference's geometry overrides (`0x76d080`/`0x76d0d0`) answer the bbox extent whenever no size is authored, `bboxExtent · 768·√(a²+1) · layoutScale` FrameXML units (`1280 · extent` at 4:3), written into the pane's layout input when the file's facts land, re-derived on an aspect change, and ended for good by any authored size; `SetPosition` is the same unit, which is how `0x4a7b20` centres the arrow at `½·GetWidth, ½·GetHeight` through the override — so the map arrow's sprite arm and its hand-sized 33.6 px footprint go (its rect is `0.0262 × 0.0263` layout units, 33.5 × 33.7 FrameXML units at 4:3, 41.0 × 41.2 at 16:9), and the stock `ItemAnim` pane plays the item push unadapted (`ReplaceIconTexture` on the type-14 batch, the 1000 ms clamp, the stock `OnAnimFinished`), `ContainerFrameAdapters.xml` losing 0887's Lua card and its hand-measured 42.41 × 124.72 rect — the implicit one at 16:9 — and keeping the keyring fork and the three bag verbs (2015); and the cooldown is the reference's own model: the texture-transform law `uv' = R_q((uv + t − p) ⊙ s) + p`, `p = (½, ½)`, the raw quaternion component-lerped and never normalised, is one function (`uv_transform`) with the shader's UV fold as its twin — rotation and scale tracks bake per file sequence slot beside the translation, the mat-anim table gains an affine row `[cos − 1, sin, sx − 1, sy − 1]` on `anim_slots.z` whose identity is the zero row so every static batch reads exactly what it did, and a UI tile clones the twin material per animated batch and writes both rows every frame off the pane's play head, never the world clock; the stock `Cooldown.xml` runs off the chain on 2007's two handlers, the file's four quadrant quads turned by their own rotation tracks (`0 → −90°` over each quadrant's 250 ms window, clockwise from 12 o'clock) and its alpha tracks revealing the star for the flash; retired: the native `Cooldown` widget and `SetCooldown` (an Era API 1.12 never had — `CreateFrame("Cooldown")` is the reference's unknown-type refusal now), the loader's `Model → Cooldown` substitution, the app's hand-built pie and star, and our `Cooldown.xml`; `assets/ui` is eight files (2019)
- `UpdateMapHighlight` gets its zone-level exits (B360): at zone zoom ours returned the nil tail for every cursor position, so hovering Deadwind Pass from Duskwood showed no label where 1.12 shows "Deadwind Pass"; the reference's `0x4a7fa0` runs two lookups at zone level and answers a NAME only — first the current zone's exploration-gated overlay list (the builder at `0x4a6ad9` gating on the explored byte), each row's HitRect scaled by 1/1002 and 1/668 against the normalized cursor, edges inclusive, the first hit naming its Area1, then the continent grid re-windowed through the displayed zone's own rect, naming the neighbouring zone or city and nothing for the displayed zone itself — and only the name-only tail is reachable from there, fileName nil and the six coords zero, so the stock frame hides the highlight quad, as the director's own 1.12 shot shows; and `SetVerticalScroll` stores the offset as given (B370, B363): the reference's `0x786db0` compares the new offset against the old and writes it to `[+0x328]` verbatim, `0x787100` re-anchors the scroll child off it, and the range at `[+0x320]` is never read on that path — every clamp the reference exhibits is FrameXML's, through the scroll bar's `[min, max]`; ours clamped into `[0, GetVerticalScrollRange()]`, the child's overflow past the FRAME, which is 40 px short of where `FauxScrollFrame_Update` sends the bar on the 220-tall skills list (three rows lost) and 15 px short on the 287-tall who list (one); the setter fires `OnVerticalScroll` only on a change, as the bytes do, `BenillaScroll_Step` bounds its wheel in Lua where the reference's handler does, and the ScrollFrame kind's prose stops calling its offset unpinned (2017)
- overdraw's cheap half, the sky first: since 0588 every sky element wrote `frag_depth = 0.0`, which costs a pipeline its early-Z, so on an outdoor frame every full-screen dome fragment under the ground and the buildings was shaded in full (the gradient's `asin`, `atan2` and eight table lookups at dawn and dusk) and thrown away; one shared `sky_vertex.wgsl` — bevy's mesh vertex verbatim plus `out.position.z = 0.0` — is now the vertex stage of the gradient dome, the cloud dome, the star patches and the celestial discs and glares, and the model lane's `WOW_SKY_DEPTH` branch moves from its fragment to its vertex, so no sky fragment declares `frag_depth` and the rasterizer rejects the covered screen before the shader runs; every sky `specialize` zeroes the rasterizer bias constant the `sky_order` rung had been leaking into `DepthBiasState::constant`, harmless only while the fragment overwrote its depth, and the prose beside the pin follows it; then the retained `static_gx` pass draws BEFORE bevy's opaque pass (`StartMainPass → static_gx → MainOpaquePass`) — buildings and doodads are the frame's best occluders and a terrain fragment its dearest, six samples a pixel — so walls reject the terrain behind them instead of the reverse, the pass taking the first-use clear with it and the dev depth probe ordered after it; measured on 16 capture scenarios: 14 bit-identical, `northshire-dusk` 1 px and `water-night` 11 px, attributed to exact depth ties on static/terrain silhouettes and last-bit interpolation noise; a depth prepass and near-to-far bins are declined until a journal says where the time goes (2016)
- the grass cut goes per pixel because of a quarter-mip: `0x6813d0` sets `D3DSAMP_MIPMAPLODBIAS = +0.25` on stage 0 (`0x6813f4`) once per frame before the detail-doodad pass — capture-confirmed on all 29 doodad batches, and outside the `[0x6b1000, 0x6b3200)` scan 2004 had called complete; it decides the whole look because the `clutter_cut` probe finds 6 of 31 shipped detail atlases carry a BINARY alpha pyramid (mip 0 has DXT3's 16 levels, every level below exactly two, both starting zones among them), so `a × ramp` degenerates to a global on/off and every texel of a leaf crosses at the same depth — Elwynn's survivor coverage is flat at 47.6 % across the whole 52.5–61.1 yd band, then 0.0 %, while the probe's box-filtered control erodes 47.7 → 20.9 over the same band, so the art has the gradient the shipped pyramid threw away, and `clutter_size` puts the median tuft at 0.92 yd tall, 1.03 yd deep, a full yard for the boundary plane to sweep; the escape is bilinear: full alpha needs a 2×2 all-opaque texel neighbourhood, and those run out between mip 2 and 3 (179/56/10/0/0/0 on the dominant Elwynn cell), so the reference's λ ≈ 2.9–3.3 sits past the cliff and the tuft erodes continuously — 2.2 % of a tuft's pixels leave in the last half-yard with the bias, 11.6 % without, 24.2 % one mip sharper; wgpu has no sampler LOD bias, so the clutter lane re-samples base colour at `view.mip_bias + 0.25`, keeping the sampler every other model batch shares at the reference's 0; ruled out on the way: our BLP decoder (all nine uploaded levels byte-identical against the archive's 52 793 BLP2s), mip regeneration, the `has_mipmaps` byte's value 2 (a plain boolean, an authoring marker), anisotropy and geometry; what it does not fix is resolution-dependent, and so is the reference's own look — λ with the bias is 3.22 at the capture's 648p but 2.48 at 1080p and 1.48 at 2160p, so at a modern resolution the reference itself pops leaf by leaf, and scaling the bias with the viewport is one reversible line left for a look call (2021)
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Important
Issues and pull requests are closed here. benilla is a solo project developed in a private tree; this repo is its export, published as squashed snapshots, so a PR here has nothing to land on. The best way to contribute is to join the Discord and report the bugs you find. Questions and ideas are welcome in the same place.
benilla speaks the original 1.12.1 protocol, so it connects to any server the real client could, and reads its game data at runtime from your own 1.12.1 install. Every file format and the network protocol are implemented from scratch, with no original client code, no third-party WoW crates, and no bundled game assets.
What works
- Formats: readers for the full asset stack (MPQ patch chain, BLP, DBC, ADT/WDT/WDL, M2, WMO), wired into Bevy as an asset source.
- World: streamed terrain out to the horizon, portal-culled WMOs with interior lighting, doodads and ground clutter, swimmable liquids, sky and weather, and the client's own day/night lighting, fog and gamma passes.
- Models: GPU-skinned M2s with the full animation controller, a near feature-complete particle system, ribbons, and animated gameobjects from doors to lifts.
- Characters: customization end to end, the armor texture composite, weapons with sheathing and enchant glows, shapeshift forms, stealth and mounts.
- Movement: a WoW-feel controller, networked movement in both directions, the server-granted modes from slow fall to roots, a follow camera with collision, boats, zeppelins and taxi flights.
- Networking: SRP6 auth through world-session crypto, the object mirror into the ECS, and live wire coverage from movement and chat through spells, party, quests, mail, trade, vendors, bank, loot, the auction house and PvP honor.
- UI: a from-scratch FrameXML + Lua engine driving the built-in interface, from the login and
character screens through the full HUD, the classic windows (guild, macros and key bindings
included), chat, nameplates, floating combat text and tooltips; third-party addons load from
a
benilla-config/AddOns/folder beside the executable (partial: AtlasLoot and Bagnon run, see below). - Combat: melee on the faithful swing law, ranged and Auto Shot, casting with GCD and cooldowns, combo points, crowd control that really holds you, and the spell visual pipeline.
- Audio: music, ambience and SFX under the client's own selection and crossfade rules, with interior and underwater transitions and zone reverb.
Where it's going
benilla is done when a 1.12.1 player can do everything here that they could in the original client, it looks and feels the same, and it runs from a download on Windows, Linux and macOS. No dates; the order is what is likely, not a promise.
- Battlegrounds and meeting stones, then the long tail of small features that separates a working client from a finished one.
- Addons, options and performance, ongoing.
- The no-brainer fixes from VanillaFixes, SuperWoW and the like.
- Playable downloads for Windows, Linux and macOS. Linux first.
Not planned: other expansions or client versions, Warden (anticheat).
Running it
You need a 1.12.1 (build 5875) client install for game data, a vanilla server to connect to, and stable Rust. Any 1.12.1 core works; vmangos is what development runs against, and cMaNGOS and the rest speak the same protocol.
WOW_DATA=/path/to/WoW/Data cargo run --release -p benilla
The server defaults to localhost:3724, the stock realmd auth port. Point WOW_HOST
at any IP or hostname, appending the auth port if yours is remapped
(WOW_HOST=play.example.com:5000). Credentials go in at the login screen, or set WOW_USER /
WOW_PASS to skip it.
Early inspiration and file format guidance came from the wowemulation-dev community, and warcraft-rs in particular.
benilla is an independent fan project, not affiliated with or endorsed by Blizzard Entertainment.
It ships no Blizzard content — no art, models, sounds, maps, MPQ contents or FrameXML; you
provide your own legally obtained 1.12.1 client. The interface code under
crates/benilla-app/assets/ui/ is ours, written to the client's own layout and API names so that
the windows look right and 1.12.1 addons find the names they expect.
World of Warcraft is a trademark of Blizzard Entertainment, Inc. Our own code is licensed under MIT or Apache 2.0, at your option.