# ink — the interface's materials The paint every screen in ANVIL CROWN is made of: the palette resolved to CSS strings, the three type faces, the responsive metrics that keep the HUD hugging the playfield instead of the window, the box primitives, the surface treatments and the motion presets. It reads no gameplay state. ```lua local Ink = require("game.interface.ink") ``` ## Colour `Ink.C` is `A.K.PALETTE` pre-resolved to `#rrggbb`. `Ink.a(name, alpha)` is the same entry as `rgba()`. `Ink.mix(a, b, t)` blends two palette entries. - `Ink.heatColour(t)` — the cannon's bar at fraction `t`, cold blue → warning yellow → hot orange. It goes by way of yellow because a direct blend of cyan and orange passes through grey, and the bar has to keep climbing in colour exactly where the player is watching it. - `Ink.hullColour(t)` — the hull at fraction `t` remaining. ## Type `Ink.F` carries the four faces named in `A.K.TYPE`: `display` (Anton), `stamp` (Archivo Black), `mono` (Berkeley Mono), `read` (Arimo). A style asks for the family name, so these are the last segment of the asset ref. ## Metrics `Ink.metrics()` measures the tall frame in screen points: | Field | What it is | |---|---| | `W`, `H` | the UI canvas | | `pxu` | points per world unit — `H / 32`, because the camera always shows 32 units of shaft | | `playHalf` | half the playfield in points: the shaft wall at world x = ±9 | | `centerX`, `margin` | the shaft's centre, and the storm to spare either side of it | | `flank`, `colW`, `pad` | the HUD column, its widest plate, the breathing room | | `outside` | whether the columns fit beside the playfield or must sit inside it | | `leftX`, `rightX`, `leftAlign`, `rightAlign` | where each column stands and which way its plates grow | | `u` | the type scale; `Ink.pt(m, n)` puts a design point into it | | `cardW` | how wide a centred card may be | On a portrait window the columns sit just inside the shaft walls. On a wider one there is storm to spare beside the playfield and they step out into it, so nothing ever covers the fight. ## Primitives and surfaces `Ink.label` / `Ink.para` / `Ink.svg` / `Ink.col` / `Ink.row` / `Ink.gap` build nodes; `Ink.at` places one absolutely; `Ink.merge` folds two style tables. `Ink.plate` is the instrument surface, `Ink.card` the frosted one, `Ink.scrim` the veil a card sits on, and `Ink.bracket` / `Ink.rule` / `Ink.stencil` the furniture. `Ink.button` is the one button shape the whole game uses. ## Motion `Ink.rise` and `Ink.fade` are entrances (stagger the delay and siblings cascade); `Ink.strike` lands a display word; `Ink.breathe`, `Ink.glowLoop` and `Ink.strobe` are idles; `Ink.toast` is in-hold-out.

# hud — the column HUD The two flank columns of ANVIL CROWN. There is no wide bar anywhere: the tall frame is the game, so the readouts run down the sides of the shaft and leave the fight in the middle of the screen alone. ```lua local Hud = require("game.interface.hud") Hud.tree(Ink.metrics()) -- the widget tree for this frame ``` `deck` calls `Hud.tree` about thirty times a second and hands the result to `ui.updateScreen`. ## Left flank — the climb - **The altitude plate.** The one number read most, struck in the display numeral face and widened past the column so it stays legible on a narrow flank. Under it, the whole 3000 m climb as one hairline. - **The tape.** A rung per 100 m with the hundreds called out, the band boundaries marked in the warning yellow, the Crown's ceiling in amber, and a lit cursor at the runner's altitude with a wedge biting in from the shaft side. The storm scrolls it. - **The air.** Climb rate with an arrow that flips and changes colour on a downdraught, and the crosswind vane — the whole lesson of the wind in one needle. - **The band chip.** SHELF / CORE / ANVIL. Once the fight at the ceiling starts, the tape gives way to the Crown's integrity column: the climb is over, so the flank reads the thing being killed, with the phase boundaries cut across it. ## Right flank — the airframe - **Heat.** The cannon's bar in a tube, drawn against the red lockout line at the top and the release line it has to fall back to. Locked, the plate goes red and strobes and the word under it reads LOCKED instead of READY. - **Hull.** Ten plate segments that burn off from the top down, colour going bright → warning yellow → alarm, with the whole plate glowing when the hull is critical. - **Score and kills**, and the pause control at the top of the column. ## Notes `Hud.crownFight()` is the one gate that decides whether the left flank shows the tape or the Crown: it wants the CROWN phase, not merely a living Crown — `crownAlive` still reads true after the kill, and the tape is what the player needs everywhere else.

# art — the interface's drawn marks Every screen in ANVIL CROWN carries something drawn as well as something written. All of it is vector, all of it in the game's palette, so it scales with the window and needs no import. ```lua local Art = require("game.interface.art") ``` | Mark | Where it goes | |---|---| | `Art.supercell` | the title's backdrop — the anvil dome, the updraught shaft, the shelf cloud and one bolt down the middle | | `Art.crown` | the win card — the mesocyclone seen from below, eyewall turning around a clear hole | | `Art.sheared` | the loss card — the storm-runner's wedge, broken across its spine | | `Art.iconWind` / `iconHeat` / `iconBolt` / `iconClimb` | one per lesson on the how-to card | | `Art.pauseGlyph` | the pause control in the HUD | Three are drawn from live values rather than fixed: - `Art.windVane(t, colour)` — a needle leaning with the crosswind, `t` from −1 to 1. - `Art.airArrow(up, colour)` — the vertical-air arrow. - `Art.cursorWedge(colour)` — the altitude tape's cursor. - `Art.rivets(count)` — a row of rivets, the plate detail that makes a column read as a made thing rather than a box.

# anvil <!-- 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.