371 lines
26 KiB
JavaScript
371 lines
26 KiB
JavaScript
// ════════════════════════════════════════════════════════════════════════
|
||
// utils.js — Pure helper functions and lookup tables.
|
||
//
|
||
// No side-effects, no DOM access, no API calls. All functions are safe
|
||
// to call server-side or in tests.
|
||
//
|
||
// Exports (in order of appearance):
|
||
// utciCategory(u) UTCI stress band → {label,bg,fg}
|
||
// precipPenalty(precipMm,snowCmH,windMs) SunScope soak-factor (°C penalty)
|
||
// windCompass8(deg) bearing → {label, snapped}
|
||
// uvSplit(uv, elevDeg) total UV index → {uvA, uvB} estimate
|
||
// SKIN_TYPES Fitzpatrick I–VI lookup table
|
||
// sunburnMinutes(uv, skinType) minutes to MED (sunburn threshold)
|
||
// burnLabel(mins) formats burn time as "12m" / "1.5h"
|
||
// VEHICLE_TYPES vehicle presets for cabin heat model
|
||
// BUILDING_TYPES building presets for indoor heat model
|
||
// cloudCategory(total,low,mid,high) → 'clear'|'wispy'|'scattered'|'overcast'
|
||
// confidenceBand(i) day-tab gradient colour + label
|
||
// moonPhaseFraction(date) 0..1 synodic phase fraction
|
||
// moonGlyph(p) phase fraction → moon emoji
|
||
// skyGradientForElev(e, isRising) solar elevation → {top,bot} hex pair
|
||
// skyFillForElev(e, isRising) convenience single-colour sky fill
|
||
// grassFillForElev(e) solar elevation → {top,bot} ground hex
|
||
// ════════════════════════════════════════════════════════════════════════
|
||
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
// UTCI THERMAL STRESS BANDS — the coloured pills in the table.
|
||
// ───────────────────────────────────────────────────────────────────
|
||
// To recolour any band, change its bg/fg hex code. To shift the
|
||
// boundary between bands (e.g. make "Comfortable" wider), change the
|
||
// `if (u < …)` thresholds. Order matters — they're checked top-down.
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
export function utciCategory(u) {
|
||
if (u < -40) return { label: 'Extreme cold', bg: '#1a1438', fg: '#fff' };
|
||
if (u < -27) return { label: 'Very strong cold', bg: '#23408f', fg: '#fff' };
|
||
if (u < -13) return { label: 'Arctic', bg: '#3f73c4', fg: '#fff' };
|
||
if (u < 0) return { label: 'Freezing', bg: '#7eb0e0', fg: '#1a1612' };
|
||
if (u < 9) return { label: 'Cold', bg: '#bcd9ec', fg: '#1a1612' };
|
||
if (u < 18) return { label: 'Chilled', bg: '#c8dcc0', fg: '#1a1612' };
|
||
if (u < 26) return { label: 'Comfortable', bg: '#4a8a3a', fg: '#fff' };
|
||
if (u < 32) return { label: 'Moderate heat', bg: '#e8c547', fg: '#1a1612' };
|
||
if (u < 38) return { label: 'Strong heat', bg: '#dc8a3a', fg: '#1a1612' };
|
||
if (u < 46) return { label: 'Very strong heat', bg: '#c44a3a', fg: '#fff' };
|
||
return { label: 'Extreme heat', bg: '#7a1a1a', fg: '#fff' };
|
||
}
|
||
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
// SOAK-FACTOR — SunScope's original rain/snow penalty.
|
||
// ───────────────────────────────────────────────────────────────────
|
||
// This is what makes "UTCI+P" different from plain UTCI. It subtracts
|
||
// extra felt-temperature for rain (wet clothing = evaporative chill)
|
||
// and snow (wet snow is brutal). Wind amplifies the rain penalty.
|
||
// Calibrated by feel — adjust the multipliers if you find it too
|
||
// strong/weak. The big number "7" caps the max rain penalty so a
|
||
// freak 50mm/h reading can't make UTCI nonsensical.
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
export function precipPenalty(precipMm, snowCmH, windMs) {
|
||
let penalty = 0;
|
||
if (precipMm > 0) {
|
||
const base = Math.min(7, 1.4 * Math.pow(precipMm, 0.55) + precipMm * 0.28);
|
||
const windMult = 1 + Math.min(0.35, windMs * 0.025);
|
||
penalty += base * windMult;
|
||
}
|
||
if (snowCmH > 0) penalty += Math.min(6, 2.2 + snowCmH * 1.6);
|
||
return -Math.round(penalty * 10) / 10;
|
||
}
|
||
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
// WIND COMPASS — meteorological bearing (deg FROM) → 8-point label.
|
||
// ───────────────────────────────────────────────────────────────────
|
||
// 0/360 = wind FROM north. The pointer in WindVane should rotate so
|
||
// the arrow's tail points to this bearing (i.e. shows where the wind
|
||
// comes from), matching how real weather vanes behave.
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
export function windCompass8(deg) {
|
||
if (deg == null || isNaN(deg)) return { label: '—', snapped: 0 };
|
||
const dirs = ['N','NE','E','SE','S','SW','W','NW'];
|
||
const idx = Math.round(((deg % 360) + 360) % 360 / 45) % 8;
|
||
return { label: dirs[idx], snapped: idx * 45 };
|
||
}
|
||
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
// UV-A / UV-B SPLIT (estimate, not measurement).
|
||
// ───────────────────────────────────────────────────────────────────
|
||
// Open-Meteo gives a total erythemal UV index. UV-A reaches the
|
||
// surface much more reliably than UV-B; UV-B is far more sensitive
|
||
// to solar elevation because of atmospheric path length.
|
||
//
|
||
// Cheap model:
|
||
// At noon (sun overhead) the UV-B share of total UV index is ~15%,
|
||
// UV-A about 85%. Below ~10° solar elevation, UV-B falls off fast.
|
||
// We return two pseudo-"index" numbers so the columns are in the
|
||
// same units the user already understands.
|
||
// Label these as estimates in the UI.
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
export function uvSplit(uv, elevDeg) {
|
||
if (!uv || uv <= 0 || elevDeg <= 0) return { uvA: 0, uvB: 0 };
|
||
const sinE = Math.sin(elevDeg * Math.PI / 180);
|
||
const uvbFr = Math.max(0.005, Math.min(0.15, 0.15 * Math.pow(sinE, 1.6)));
|
||
const uvaFr = 1 - uvbFr;
|
||
return { uvA: uv * uvaFr, uvB: uv * uvbFr };
|
||
}
|
||
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
// SUNBURN TIME — minutes to MED for the chosen Fitzpatrick skin type.
|
||
// ───────────────────────────────────────────────────────────────────
|
||
// Standard erythemal model: time_min ≈ base_minutes[type] / UV_index.
|
||
// Numbers are the well-known "unprotected, midday, no sunscreen"
|
||
// reference times at UV = 1. Returns Infinity when UV is 0 (night).
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
export const SKIN_TYPES = {
|
||
I: { name: 'I · Very fair', base: 67 },
|
||
II: { name: 'II · Fair', base: 100 },
|
||
III: { name: 'III · Light', base: 200 },
|
||
IV: { name: 'IV · Mid', base: 300 },
|
||
V: { name: 'V · Dark', base: 400 },
|
||
VI: { name: 'VI · Very dark', base: 500 },
|
||
};
|
||
export function sunburnMinutes(uv, skinType = 'II') {
|
||
if (!uv || uv <= 0) return Infinity;
|
||
const base = (SKIN_TYPES[skinType] || SKIN_TYPES.II).base;
|
||
return base / uv;
|
||
}
|
||
export function burnLabel(mins) {
|
||
if (!isFinite(mins)) return '—';
|
||
if (mins >= 480) return '8h+';
|
||
if (mins >= 60) return `${(mins/60).toFixed(1)}h`;
|
||
return `${Math.round(mins)}m`;
|
||
}
|
||
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
// VEHICLE TYPES — presets for the cabin heat model.
|
||
// ───────────────────────────────────────────────────────────────────
|
||
// Each entry tweaks the physical levers in calcVehicleInteriorTemp:
|
||
// albedo — how much solar the bodywork reflects (0 = black, 1 = mirror)
|
||
// glazingArea — relative sun-exposed glass area (1.0 = typical car)
|
||
// bodyU — effective body/panel conductance into the cabin. Cars are
|
||
// thin metal/glass boxes; motorhomes/caravans have insulated
|
||
// sandwich panels, commonly around 25–35 mm thick.
|
||
// hCabinLoss — effective heat rejection/infiltration from the cabin air.
|
||
// thermalMass — lower values mean the interior warms more slowly in the hour.
|
||
// retainedWarmth — occupied insulated living spaces hold heat from previous
|
||
// hours, people, appliances, and background heating.
|
||
// internalGain — small living-space warmth boost when closed up.
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
export const VEHICLE_TYPES = {
|
||
car: { name: 'Car / Hatchback', albedo: 0.25, glazingArea: 1.0, bodyU: 4.0, hCabinLoss: 20, thermalMass: 1.00, retainedWarmth: false, internalGain: 0.0 },
|
||
mpv: { name: 'MPV / People Carrier', albedo: 0.25, glazingArea: 1.3, bodyU: 4.0, hCabinLoss: 20, thermalMass: 1.00, retainedWarmth: false, internalGain: 0.0 },
|
||
suv: { name: 'SUV / 4x4', albedo: 0.22, glazingArea: 1.1, bodyU: 3.8, hCabinLoss: 19, thermalMass: 0.95, retainedWarmth: false, internalGain: 0.0 },
|
||
motorhome: { name: 'Motorhome / Campervan', albedo: 0.55, glazingArea: 0.25, bodyU: 0.9, hCabinLoss: 12, thermalMass: 0.35, retainedWarmth: true, internalGain: 1.2 },
|
||
caravan: { name: 'Caravan (towed)', albedo: 0.60, glazingArea: 0.22, bodyU: 0.8, hCabinLoss: 11, thermalMass: 0.35, retainedWarmth: true, internalGain: 1.2 },
|
||
};
|
||
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
// BUILDING TYPES — presets for the indoor temperature model.
|
||
// ───────────────────────────────────────────────────────────────────
|
||
// Each preset drives both calcIndoorTempPass and calcManagedIndoorTempPass.
|
||
//
|
||
// uWall W/m²K Effective envelope U-value. Higher = faster response
|
||
// to outdoor swings, less insulation.
|
||
// lagHours h Thermal mass time constant. Heavier construction = longer
|
||
// lag before indoor temp follows outdoor changes.
|
||
// glazingRatio — Fraction of floor area that is window. More glass = more
|
||
// solar gain in summer, more heat loss in winter.
|
||
// gValue — Solar heat gain coefficient of glazing. 0.63 = standard
|
||
// double glazing; 0.3 = modern low-e triple.
|
||
// orientFactor — Fraction of windows facing the sun at any given time.
|
||
// 0.5 = random orientation; 0.8 = south-facing conservatory.
|
||
// curtainBlock — Fraction of solar gain blocked when managed (curtains
|
||
// closed). Thick lined curtains ≈ 0.80; blinds ≈ 0.50.
|
||
// ventAlpha — Blending weight per hour when smart ventilation is open.
|
||
// Higher = more air changes per hour.
|
||
// solarScale — Converts effective window solar gain into an indoor
|
||
// temperature lift. Lower values mean more thermal mass.
|
||
// baseTemp — Occupied/retained warmth baseline for normal homes.
|
||
// internalGain — Small heat gain from people, appliances, and background use.
|
||
// retainedScale — How strongly the building holds above-outdoor warmth in
|
||
// cool conditions. Higher = better retained warmth.
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
export const BUILDING_TYPES = {
|
||
brick: { name: 'Brick (typical)', uWall: 0.35, lagHours: 4, glazingRatio: 0.16, gValue: 0.63, orientFactor: 0.50, curtainBlock: 0.80, ventAlpha: 0.25, solarScale: 0.10, baseTemp: 16.5, internalGain: 0.8, retainedScale: 0.35 },
|
||
modern: { name: 'Modern / Well insulated', uWall: 0.18, lagHours: 5, glazingRatio: 0.20, gValue: 0.30, orientFactor: 0.50, curtainBlock: 0.70, ventAlpha: 0.20, solarScale: 0.08, baseTemp: 17.0, internalGain: 0.8, retainedScale: 0.55 },
|
||
victorian: { name: 'Victorian Terrace', uWall: 0.55, lagHours: 5, glazingRatio: 0.12, gValue: 0.63, orientFactor: 0.50, curtainBlock: 0.80, ventAlpha: 0.30, solarScale: 0.10, baseTemp: 16.0, internalGain: 0.7, retainedScale: 0.25 },
|
||
stone: { name: 'Stone / Granite Cottage', uWall: 0.45, lagHours: 7, glazingRatio: 0.10, gValue: 0.63, orientFactor: 0.50, curtainBlock: 0.75, ventAlpha: 0.25, solarScale: 0.08, baseTemp: 15.5, internalGain: 0.6, retainedScale: 0.40 },
|
||
timber: { name: 'Timber Frame / New Build', uWall: 0.22, lagHours: 2, glazingRatio: 0.22, gValue: 0.35, orientFactor: 0.50, curtainBlock: 0.70, ventAlpha: 0.35, solarScale: 0.08, baseTemp: 17.0, internalGain: 0.8, retainedScale: 0.45 },
|
||
flat: { name: 'Top-floor Flat', uWall: 0.40, lagHours: 3, glazingRatio: 0.18, gValue: 0.63, orientFactor: 0.50, curtainBlock: 0.75, ventAlpha: 0.20, solarScale: 0.11, baseTemp: 17.0, internalGain: 0.9, retainedScale: 0.45 },
|
||
conservatory:{ name: 'Conservatory / Sun Room', uWall: 1.20, lagHours: 1, glazingRatio: 0.70, gValue: 0.72, orientFactor: 0.70, curtainBlock: 0.50, ventAlpha: 0.50, solarScale: 0.045, baseTemp: 12.0, internalGain: 0.2, retainedScale: 0.05 },
|
||
};
|
||
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
// CLOUD CATEGORY — pick one of 4 icon styles from low/mid/high split.
|
||
// ───────────────────────────────────────────────────────────────────
|
||
// Returns: 'clear' | 'wispy' | 'scattered' | 'overcast'
|
||
// Uses total cover for headline level, but biases towards 'wispy'
|
||
// when only high cloud is present (cirrus barely blocks the sun).
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
export function cloudCategory(total, low, mid, high) {
|
||
const t = total ?? 0;
|
||
const l = low ?? 0;
|
||
const m = mid ?? 0;
|
||
const h = high ?? 0;
|
||
if (t < 10) return 'clear';
|
||
// Mostly high cloud with little low/mid → wispy regardless of % total
|
||
if (h > 40 && l < 25 && m < 25) return 'wispy';
|
||
if (t < 40) return 'wispy';
|
||
if (t < 75) return 'scattered';
|
||
return 'overcast';
|
||
}
|
||
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
// CONFIDENCE BANDS — smooth high-noon → sunset gradient on day tabs.
|
||
// ───────────────────────────────────────────────────────────────────
|
||
// `i` is the day index (0 = today, 13 = day 14).
|
||
//
|
||
// Each day gets its own shade, interpolated between two endpoint
|
||
// colours. To re-skin the gradient (say, blue-to-purple instead of
|
||
// sunset), just change the four RGB endpoint arrays below.
|
||
//
|
||
// bg = tab background (lighter on day 0, darker on day 13)
|
||
// edge = active-tab underline + slim border on the banner
|
||
// tint = soft wash on the confidence banner above the table
|
||
// label = qualitative zone name shown in the banner ("Golden hour")
|
||
//
|
||
// The label switches in 4 stages so users still see a friendly
|
||
// description ("you're in the trustworthy zone" vs "this is an
|
||
// outlook"). The tab background itself flows smoothly day to day.
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
export function confidenceBand(i) {
|
||
// Position along the gradient: 0 on day 0, 1 on day 13.
|
||
const t = Math.min(1, Math.max(0, i / 13));
|
||
|
||
// ENDPOINTS — change these four RGB arrays to re-skin the gradient.
|
||
const bgStart = [255, 247, 214]; // #fff7d6 pale yellow (high noon)
|
||
const bgEnd = [232, 152, 104]; // #e89868 terracotta (sunset)
|
||
const edgeStart = [245, 231, 161]; // #f5e7a1 soft golden
|
||
const edgeEnd = [196, 115, 64]; // #c47340 burnt umber
|
||
|
||
// Linear interpolation between the two endpoints.
|
||
const lerp = (a, b) => Math.round(a + t * (b - a));
|
||
const mix = (s, e) => [lerp(s[0], e[0]), lerp(s[1], e[1]), lerp(s[2], e[2])];
|
||
|
||
const [br, bg, bb] = mix(bgStart, bgEnd);
|
||
const [er, eg, eb] = mix(edgeStart, edgeEnd);
|
||
|
||
return {
|
||
bg: `rgb(${br}, ${bg}, ${bb})`,
|
||
edge: `rgb(${er}, ${eg}, ${eb})`,
|
||
tint: `rgba(${er}, ${eg}, ${eb}, 0.22)`,
|
||
// Qualitative confidence label (camera-focus metaphor —
|
||
// on-brand for SunScope, and instantly readable).
|
||
label: i < 3 ? 'Pin-sharp' // days 1–3 highest skill
|
||
: i < 7 ? 'Sharp' // days 4–7 solid
|
||
: i < 10 ? 'Soft focus' // days 8–10 trends only
|
||
: 'Blurry', // days 11–14 outlook only
|
||
};
|
||
}
|
||
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
// MOON PHASE — works out which moon emoji to show on night hours.
|
||
// ───────────────────────────────────────────────────────────────────
|
||
// Returns a fraction 0..1:
|
||
// 0.00 = new moon 0.50 = full moon
|
||
// 0.25 = first quarter 0.75 = last quarter
|
||
// The maths is a simple synodic-period calculation referenced from
|
||
// a known new moon (6 Jan 2000). Accurate to within a few hours.
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
export function moonPhaseFraction(date) {
|
||
const JD = date.getTime() / 86400000 + 2440587.5;
|
||
const syn = 29.530588;
|
||
const ref = 2451550.1;
|
||
let p = ((JD - ref) % syn) / syn;
|
||
if (p < 0) p += 1;
|
||
return p;
|
||
}
|
||
export function moonGlyph(p) {
|
||
// +0.5 offset rounds to nearest phase (avoids flickering on exact boundaries)
|
||
return ['🌑','🌒','🌓','🌔','🌕','🌖','🌗','🌘'][Math.floor(p * 8 + 0.5) % 8];
|
||
}
|
||
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
// SKY GRADIENT — top/bottom colour pair for the SkyScope disk gradient.
|
||
// ───────────────────────────────────────────────────────────────────
|
||
// isRising: true when sun is climbing (local hour < 12).
|
||
//
|
||
// Sunrise palette → reds, oranges, yellows at the horizon.
|
||
// Sunset palette → pinks, purples, mauves at the horizon.
|
||
// Both share the same deep blue zenith at high elevations.
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
// Sky colour keyframes — [elevation, topHex, botHex] for rising and setting sun.
|
||
// Colours are smoothly interpolated between adjacent keyframes.
|
||
const SKY_KEYS_RISING = [
|
||
[-18, '#0e0c28', '#1a1538'], // deep night
|
||
[-14, '#1e1a50', '#3a2f60'], // nautical twilight
|
||
[ -8, '#2a3a6a', '#a04828'], // pre-dawn: indigo → burnt sienna
|
||
[ -3, '#4a7aaa', '#e8622a'], // horizon band: deep blue → vivid red-orange
|
||
[ 3, '#6aaddb', '#ffb347'], // golden hour: blue → warm amber
|
||
[ 10, '#7cc5ec', '#c8e3ee'], // low sun: pale blue sky
|
||
[ 30, '#5bb8e8', '#9fd3ef'], // mid-day blue
|
||
[ 60, '#2e8fd4', '#7cc8ef'], // high noon: rich deep blue
|
||
[ 90, '#1a7abf', '#60b8e8'], // zenith (sun directly overhead)
|
||
];
|
||
const SKY_KEYS_SETTING = [
|
||
[-18, '#0e0c28', '#1a1538'],
|
||
[-14, '#1e1a50', '#3a2f60'],
|
||
[ -8, '#5a3572', '#c07080'], // dusk: purple → dusty rose/mauve
|
||
[ -3, '#7a5090', '#e8826a'], // horizon band: violet → coral/pink
|
||
[ 3, '#7b8fc4', '#ffb877'], // golden hour: blue-violet → golden
|
||
[ 10, '#7cc5ec', '#c8e3ee'],
|
||
[ 30, '#5bb8e8', '#9fd3ef'],
|
||
[ 60, '#2e8fd4', '#7cc8ef'],
|
||
[ 90, '#1a7abf', '#60b8e8'],
|
||
];
|
||
|
||
function hexToRgb(hex) {
|
||
const n = parseInt(hex.slice(1), 16);
|
||
return [(n >> 16) & 255, (n >> 8) & 255, n & 255];
|
||
}
|
||
function rgbToHex([r, g, b]) {
|
||
return '#' + [r, g, b].map(v => Math.round(v).toString(16).padStart(2, '0')).join('');
|
||
}
|
||
function lerpRgb(a, b, t) {
|
||
return a.map((v, i) => v + t * (b[i] - v));
|
||
}
|
||
|
||
function interpolateSkyKeys(keys, e) {
|
||
// Clamp to key range
|
||
if (e <= keys[0][0]) return { top: keys[0][1], bot: keys[0][2] };
|
||
if (e >= keys[keys.length - 1][0]) {
|
||
const k = keys[keys.length - 1];
|
||
return { top: k[1], bot: k[2] };
|
||
}
|
||
// Find bracketing keyframes
|
||
let lo = keys[0], hi = keys[1];
|
||
for (let i = 1; i < keys.length; i++) {
|
||
if (keys[i][0] >= e) { lo = keys[i - 1]; hi = keys[i]; break; }
|
||
}
|
||
const t = (e - lo[0]) / (hi[0] - lo[0]);
|
||
const top = rgbToHex(lerpRgb(hexToRgb(lo[1]), hexToRgb(hi[1]), t));
|
||
const bot = rgbToHex(lerpRgb(hexToRgb(lo[2]), hexToRgb(hi[2]), t));
|
||
return { top, bot };
|
||
}
|
||
|
||
export function skyGradientForElev(e, isRising) {
|
||
return interpolateSkyKeys(isRising ? SKY_KEYS_RISING : SKY_KEYS_SETTING, e);
|
||
}
|
||
|
||
// ─── skyFillForElev ────────────────────────────────────────────────────────
|
||
// Convenience single-colour fill for contexts that don't need a gradient
|
||
// (e.g. solid background chips). Returns the horizon (bottom) colour.
|
||
export function skyFillForElev(e, isRising = false) {
|
||
return skyGradientForElev(e, isRising).bot;
|
||
}
|
||
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
// GRASS FILL — ground-strip colour keyed to solar elevation.
|
||
// ───────────────────────────────────────────────────────────────────
|
||
// Mirrors the sky palette so the SkyScope disk reads naturally: vivid
|
||
// green at noon, amber at golden hour, purple-dark at twilight/night.
|
||
// Returns {top, bot} for a subtle two-stop ground gradient.
|
||
// ═══════════════════════════════════════════════════════════════════
|
||
export function grassFillForElev(e) {
|
||
if (e > 60) return { top: '#92cc50', bot: '#5e9630' }; // blazing noon
|
||
if (e > 30) return { top: '#86c44a', bot: '#558a2e' }; // bright midday
|
||
if (e > 10) return { top: '#7ab846', bot: '#4d802c' }; // mid-day
|
||
if (e > 3) return { top: '#b8a83e', bot: '#7a6a26' }; // golden-hour glow
|
||
if (e > -3) return { top: '#c08048', bot: '#7a4a2a' }; // sunrise/sunset embers
|
||
if (e > -8) return { top: '#665884', bot: '#3e3556' }; // civil twilight purple
|
||
if (e > -14) return { top: '#363356', bot: '#1c1a34' }; // nautical night
|
||
return { top: '#201d3a', bot: '#0d0b20' }; // astronomical night
|
||
}
|