# miasma_low <!-- zero:scaffolded-readme --> <!-- Replace the line below with what this material provides and who consumes it, then delete both comment lines. --> TODO: describe this material.

# nb <!-- zero:scaffolded-readme --> <!-- Replace the line below with what this module provides and who consumes it, then delete both comment lines. --> TODO: describe this module.

# shaft <!-- zero:scaffolded-readme --> <!-- Replace the line below with what this material provides and who consumes it, then delete both comment lines. --> TODO: describe this material.

# lantern <!-- zero:scaffolded-readme --> <!-- Replace the line below with what this material provides and who consumes it, then delete both comment lines. --> TODO: describe this material.

# Backdrop (component) The parallax driver of Ashcross. The camera is orthographic, so a quad parked thirty units behind the street tracks the camera exactly and reads as glued to it: every bit of depth in this game is scripted, and this is where. ## Modes **`mode = "band"`** — the entity is a full-frame quad locked to the camera, and the district it shows lives inside its material as a procedural pattern. The component writes `scroll_x` / `scroll_y` on that material every frame at `spanX / worldWidth * parallax * cameraX` (and the same in y). Nothing recycles because the pattern never ends. **`mode = "anchor"`** — the entity stands at a fixed district point (`anchorX`, `anchorY`) and is drawn at `cam + (anchor - cam) * parallax`. Lanterns, braziers, shafts and hanging props ride a band this way, so a lamp on the mid band slides past at exactly the rate the wall behind it does. `parallax` is the whole vocabulary: 0 is infinitely far (locked to the eye), 1 moves exactly with the street, above 1 is the foreground band that overtakes it. ## Transient lights Set `lifetime` above zero and the entity swells to `peakW` x `peakH` over `attack` seconds, shrinks away over the rest, drifts up at `rise`, and despawns itself. The fade is carried by the entity's SCALE, not by its material, because a material is shared by every puff wearing it and they have to be able to die at different moments. ## Notes - The material is taken from the entity's own `Model`, never resolved by name: a component may not resolve an asset from a computed string, and two entities that share a band should share its scroll. Call `:rebind()` after swapping the `Model`'s material. - Culling (`cullMargin`) collapses the quad to zero scale rather than deactivating the entity. An inactive entity stops running its components, and a component that has stopped running can never decide to come back. - `editorUpdate` runs the same driver as `update`, so the bands line up in edit mode as well as in play — every screenshot of this game is taken from a scene camera either way. ## Fields `mode` `parallax` `bandZ` · band: `worldWidth` `worldHeight` `spanX` `spanY` `phaseX` `phaseY` · anchor: `anchorX` `anchorY` `bob` `bobSpeed` · transient: `lifetime` `attack` `peakW` `peakH` `rise` · both: `cullMargin`. ## Methods `:rebind()` — re-read the material from the `Model`. `:setAnchor(x, y)` — move a prop to a new district point immediately.

# Camera2D — the camera of Ashcross The only camera in Nine Bells. Orthographic, side-on, never rotating, never leaving the `NB.CAMERA.z` plane; it looks straight down -Z at a flat city on a 1080x1440 portrait screen, which covers sixteen world units vertically and only twelve across. ## In play It follows `NB.state.doctor` — not an entity, because the traverse slice runs its own 2D physics and writes the doctor's position into the blackboard. There is a deadzone the doctor moves inside without the camera answering (narrow horizontally, because there is almost no horizontal room to give away), a lead in the direction of travel scaled by run speed, and a softer vertical time constant so a landing reads as weight. It publishes where it ended up into `NB.state.cameraX` / `cameraY`, which is what the backdrop reads for its scripted parallax and what every slice reads to decide whether a thing is on screen. ## When a moment takes it | Call | What it does | |---|---| | `:panTo(x, y, seconds, ease)` | a TIMED move along an eased curve; `:isPanning()` says when it has arrived | | `:zoomTo(height, seconds, ease)` | a TIMED change of lens. 16 is the playing frame, 10 a push onto a face, 22 the district opening out | | `:setDrift(vx, vy)` | a slow creep added to a driven shot — a held frame that drifts is alive, one that is nailed down is a still | | `:kick(amount)` | the shake: a bell, a hard landing, a floor giving way | | `:snapTo(x, y)` | a cut. Take the override too (`:driveTo`) or the follow walks it straight back | | `:driveTo(x, y)` | the untimed, damped drive | | `:release()` | hand the shot back to the doctor, cancelling any pan and drift | | `:setBounds(minX, maxX, minY, maxY)` | the city slice's limits on the FOLLOW. A driven shot ignores them: a staged moment may look above the roofline | | `:pose()` | where the shot is, with the shake taken back out | Ease names: `linear` `inQuad` `outQuad` `inOutQuad` `outCubic` `inOutCubic` `inOutSine` `outExpo`. ## It also carries the staging clock `game.stage` installs `NB.ext.stageTick` and `NB.ext.stagePostTick`; this component calls them once a frame, in edit mode as well as in play, so a moment can be rehearsed without entering play and locking the VFS for the other slices. The pre-tick runs before the pose, so a cue that starts a pan this frame is answered this frame; the post-tick runs after it, which is where anything held in front of the lens is placed so it never lags the shake. Both calls are guarded: a staging module mid-edit can never take the camera down with it. ## Usage ```lua rig.component.add("Camera", { projection = "orthographic", behavior = asset.resolve("game.Camera2D", "component"), }) ``` Owned by the staging slice. See `/zero/source/design/spec.md`.

# censerlight <!-- zero:scaffolded-readme --> <!-- Replace the line below with what this material provides and who consumes it, then delete both comment lines. --> TODO: describe this material.

# pool <!-- zero:scaffolded-readme --> <!-- Replace the line below with what this material provides and who consumes it, then delete both comment lines. --> TODO: describe this material.