Lume

The big one: the rendering engine was rebuilt in-house.

• Same look, faster loads — and custom materials keep working exactly as documented: measured against the full catalog, every published custom material and look keeps working exactly as before.
• Games use a fraction of the GPU power they used to (typically 30–95% less), which means cooler machines, quieter fans, and much longer battery life at higher frame rates.

And everything else that lands with it:

• Switching camera kinds (e.g. a first-person ↔ third-person toggle via setCamera) now cuts instantly to the new camera instead of gliding the view through your character. Zoom easing and camera smoothing within one camera are unchanged.
• Painting grass and flowers feels completely different now: strokes go straight into the massive GPU grass system, so you can paint whole meadows — hundreds of thousands of blades and blooms — with instant feedback under the brush.
• Erase works both ways: clear the flowers you painted, or thin out naturally-growing grass to carve paths and clearings.
• Every decoration layer in your world gets its own Foliage brush, so you can hand-shape where the grass grows.
• Edits to generator scripts now reach everyone in the room. Before, if you (or Savi) edited a script that generates scattered objects or scripted spline shapes, those objects — flowers, rocks, cloud-seas, even player rigs — could turn permanently invisible for everyone else, surviving rejoins, with no error anywhere. Now a generator edit rebuilds those objects for the whole room the instant it applies.
• Grass is alive now! Fields sway and gust with your world's wind direction — turn the wind and the whole meadow leans with it.
• One line gets you a full meadow: deck: "meadow" (or clover, alpine, autumn, lavender) plants tuned grass and flowers that inherit your ground colors.
• Ground cover is way denser near you — thick carpets instead of sparse tufts — and every blade varies a little in color, so fields stop looking flat.
• New worlds start with a living meadow instead of bare ground.
• Buttons, doors, chests, shops, and vehicles now respond the instant any player presses — not only for one player in the room.
• When a sprite animation can't be generated, Savi now learns exactly why and can fix it right away — instead of everyone waiting on retries that could never succeed.
• Point and spot lights now illuminate every material — matte (Lambert), glossy (Phong), cartoon (Toon), custom scripted materials, and water — not just standard PBR surfaces, sprites, and tilemaps. A lamp next to a toon house lights the house; lanterns reflect in lakes at night.
• Switching a place between 3D and 2D while people are in it now updates everyone's look immediately. Before, players (and objects) kept their old-mode visuals — in a 2D world your character could turn invisible because it was still wearing its 3D avatar — until each person refreshed. Flipping back to 3D restores 3D models and profile avatars the same way. Also fixed 2D worlds silently not showing image-based (png) models placed in the world spec.
• A lag spike no longer permanently costs you your drawn textures or scripted materials. Before, one bad stretch (a busy device, a backgrounded tab) could park a texture script or flatten your scripted materials for the whole session — things like a sprite's drawn halo or a planet's shader skin went missing until someone refreshed. Now the engine retries before parking, one stalled texture variant no longer takes down its siblings, and once the frame rate recovers, parked work comes back on its own — carefully, one piece at a time, re-parking only a piece that actually causes trouble again.
• Walking through a portal now starts loading the destination's models, textures, and sounds immediately instead of after the server confirms the travel — and places you haven't visited yet warm quietly in the background during idle frames, current place first. Transitions hold their loading veil for less and same-dimension arrivals land with real art instead of placeholders popping in. Nothing costs the current place a frame, and nothing changes about who is allowed to travel.
• Other players and NPCs now start moving with a visible wind-up and settle when they stop, instead of moonwalking into their walk cycle or skating to a halt — network delay reads as character weight, not lag. When someone's connection stalls, their avatar eases to rest instead of running in place. Your own character is untouched, and it stays out of the way of your own animation: actors driven by your mixer channels or an authored speedOverride are never touched, and interpolation: false disables it with the rest of motion smoothing.
• Hits land where they look like they land: on jittery connections, damage numbers, hit flashes, and impact sounds from other players now present the same frame as the body they land on, instead of flashing up to ~130 ms ahead of it. Your own actions stay instant.
• Behind-the-scenes: sprite loading failures now record exactly why they failed, so problems get fixed faster.
• HUD animations driven by game state (momentum counters, timers, scale pops, fades computed in your ui.js render) update 3× more often — 30 times per second, up from 10 — so they look noticeably smoother. For perfectly smooth motion at any display refresh, keep using CSS transitions/keyframes in your UI html. New knob: api.patchEngine({ ui: { targetFps: 10 } }) (5–30) if you'd rather dial a mostly-static HUD down.
• A second of flaky wifi no longer leaves permanent broken-image icons in your game's UI. Images that fail to load now quietly retry on their own (after 2s, then 8s), and even one that gives up comes back on the next screen change or image swap — refreshing the page is no longer the only fix. Your own onerror fallbacks on images keep working exactly as you wrote them.
• Guards, creatures, and anything using canSee/awarenessOf now notice players the moment they come into view instead of up to a couple of tenths of a second late. Sneaking past a patrol, chases, and "the shopkeeper looks up as you walk in" all feel more alive — and the authored feel (awareness rise time, vision cones, gradual loss of sight) is untouched.
• Lights work in 2D worlds again — lanterns pool warm light on the ground, windows glow onto the yard, a firefly carries its own drifting glow — and dark scenes sit at the same brightness they did before the renderer swap instead of reading washed-out.
• Fixed custom materials sometimes staying stuck as flat gray/tinted after joining or refreshing a world — the engine now notices when a material didn't finish building at join and retries it automatically, including after reconnects.
• Custom geometry that swaps textures mid-mesh (a table with oak top and weathered legs) shows its textures again, and lantern-style objects that mix glass with solid parts draw in the right order — the solid cap and base sit in front of or behind the glass like they should, instead of the glass smearing over them.
• castShadow: false and receiveShadow: false on objects now actually work — models stop casting when told not to, and both models and primitives set to not receive shadows shade fully lit instead of darkening anyway. Worlds that turned shadows off per object for looks or performance get that back.
• Textured surfaces no longer turn flat white when a world mixes texture sizes — the iso-town cars keep their paint and rust next to the playground's oak tables, no matter which loads first.
• Fixed models turning entirely white when a wind-sway or other vertex-animation material script was applied — the staging-zoo pine that waved correctly but lost its bark and foliage colors. A script that only moves vertices now keeps the model's own textures, colors, and vertex paint; scripts that set their own color still win.
• Fixed skinned characters in crowds sinking waist-deep into the ground (and rendering at the wrong size) when their script asked for an animation name the model doesn't have — they now stand on their feet in the model's rest pose, exactly like a single copy of the same character would.
• Lights, particles, and scripts you attach to an object's children now actually run when your game boots — before, they could silently do nothing until an unrelated edit woke them up. And any script can now address a child object by the id you gave it in the spec, not just from its own parent.
• When an asset's generation fails hard on the server, your game now stops hammering the dead asset (which was slowing everything else down, including the retry that would fix it) — Savi gets one clear message saying what happened and that regenerating the asset is the fix, and once it's regenerated it loads again on its own.
• If your scripts spawn objects into a place nobody has entered yet (like pre-building a match arena from a lobby), you now get a clear warning telling you those objects would silently vanish — with the fix: bake them into definePlace's objects[] or create them at entry with enterPlace createIfMissing.
• Worlds whose scripts re-set the same values on every boot no longer jam the save pipeline — the engine now recognizes "nothing actually changed" and skips those saves instead of retrying them forever, so real edits and state changes save promptly again.
• Characters and objects with "breathing" or squash-and-stretch scale animations no longer secretly rebuild their physics every frame — worlds full of animated creatures run smoother, and idle characters stay cheap like they're supposed to.
• When a bunch of script-generated objects appear at once (a whole block of generated buildings restocking), other players' games no longer freeze for a moment — the shapes stream in over a few frames while everything else keeps moving.
• You can outline things in up to 8 different colors at once now (up from 4). When a world asks for more than fits, the most important outlines stay visible — your god-mode selection no longer vanishes — and Savi is told exactly which outline colors got dropped instead of them silently not appearing.

Known issues (being polished on staging):

• In dense scenes with many overlapping transparent sprites, front/back ordering can still occasionally pop wrong — the specific reported cases are fixed, and deeper ordering work continues.
• Water detail is temporarily simplified: ripple normals, crest foam, and caustic sparkle use placeholder patterns until the real textures are wired into the new renderer.
• A few very advanced material scripts that reach past the documented vocabulary pause safely with a message naming what's missing instead of rendering — that vocabulary is being filled in now. Everything written from the Custom Materials and Looks docs works unchanged.