M1: object cards, time scrubber, night mode !3

merged merged by cmc on 2026-10-18 01:54 UTC · krz/moonrise:m1-interaction into main

8 files changed, +324 −28

Layout: unified · split

App/Sources/SkyModel.swift +47 −12

		@@ -4,8 +4,32 @@ import Observation
4	4	import SkyEngine
5	5	import SkyRenderer
6	6
7		/// Current place and the scene computed for it. Scenes are built off the main
8		/// thread one at a time, since Astronomy Engine is not thread-safe.
	7	/// Serializes Astronomy Engine calls, which are not thread-safe.
	8	actor Astronomer {
	9	func scene(at date: Date, from observer: Observer) throws -> SkyScene {
	10	try SkyScene(date: date, observer: observer)
	11	}
	12
	13	func details(of body: Body, at date: Date, from observer: Observer) throws -> BodyDetails {
	14	let h = try SkyEngine.horizontal(body, at: date, from: observer, refraction: true)
	15	let eq = try SkyEngine.equatorial(body, at: date, from: observer)
	16	let i = try SkyEngine.illumination(body, at: date)
	17	let rs = SkyEngine.riseSet(body, after: date, from: observer)
	18	return BodyDetails(body: body, position: h, distanceAU: eq.distance, magnitude: i.magnitude, phaseFraction: i.phaseFraction, rise: rs.rise, set: rs.set)
	19	}
	20	}
	21
	22	struct BodyDetails: Sendable {
	23	var body: Body
	24	var position: Horizontal
	25	var distanceAU: Double
	26	var magnitude: Double
	27	var phaseFraction: Double
	28	var rise: Date?
	29	var set: Date?
	30	}
	31
	32	/// Current place, the displayed time and the scene computed for them.
9	33	@MainActor
10	34	@Observable
11	35	final class SkyModel: NSObject, CLLocationManagerDelegate {
		@@ -16,9 +40,14 @@ final class SkyModel: NSObject, CLLocationManagerDelegate {
16	40	private(set) var hasLocation = false
17	41	private(set) var scene: SkyScene?
18	42	private(set) var lastBuild: Duration = .zero
	43	/// Hours from now shown by the time scrubber.
	44	var offsetHours = 0.0 { didSet { refresh() } }
	45	var displayedDate: Date { .now.addingTimeInterval(offsetHours * 3600) }
19	46
	47	let astronomer = Astronomer()
20	48	private let manager = CLLocationManager()
21	49	private var building = false
	50	private var pending = false
22	51
23	52	override init() {
24	53	super.init()
		@@ -32,22 +61,28 @@ final class SkyModel: NSObject, CLLocationManagerDelegate {
32	61	refresh()
33	62	}
34	63
35		func refresh(at date: Date = .now) {
36		guard !building else { return }
	64	/// Rebuilds the scene for the displayed time. Requests made during a build
	65	/// collapse into one rebuild when it finishes.
	66	func refresh() {
	67	guard !building else { pending = true; return }
37	68	building = true
38		let observer = observer
39		Task.detached(priority: .userInitiated) {
	69	let date = displayedDate, observer = observer, astronomer = astronomer
	70	Task {
40	71	let clock = ContinuousClock()
41	72	var scene: SkyScene?
42		let elapsed = clock.measure { scene = try? SkyScene(date: date, observer: observer) }
43		await MainActor.run {
44		self.scene = scene
45		self.lastBuild = elapsed
46		self.building = false
47		}
	73	let start = clock.now
	74	scene = try? await astronomer.scene(at: date, from: observer)
	75	lastBuild = clock.now - start
	76	if let scene { self.scene = scene }
	77	building = false
	78	if pending { pending = false; refresh() }
48	79	}
49	80	}
50	81
	82	func details(of body: Body) async -> BodyDetails? {
	83	try? await astronomer.details(of: body, at: displayedDate, from: observer)
	84	}
	85
51	86	nonisolated func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
52	87	guard let c = locations.last?.coordinate else { return }
53	88	Task { @MainActor in

App/Sources/SkyScreen.swift +123 −13

		@@ -1,3 +1,4 @@
	1	import SkyEngine
1	2	import SkyRenderer
2	3	import SwiftUI
3	4
		@@ -6,25 +7,42 @@ struct SkyScreen: View {
6	7	@State private var azimuth = 180.0
7	8	@State private var altitude = 45.0
8	9	@State private var fieldOfView = 100.0
	10	@State private var night = false
	11	@State private var selection: SkyObject?
	12	@State private var details: BodyDetails?
9	13	@GestureState private var drag: CGSize = .zero
10	14	@GestureState private var zoom: CGFloat = 1
11	15	private let stats = DrawStats()
12	16
	17	private var style: SkyStyle { night ? .night : SkyStyle() }
	18	private var ink: Color { night ? Color(red: 0.85, green: 0.12, blue: 0.08) : Color(red: 0.95, green: 0.95, blue: 0.93) }
	19
13	20	var body: some View {
14	21	GeometryReader { geo in
15		ZStack(alignment: .topLeading) {
16		Color(red: 0.043, green: 0.078, blue: 0.141).ignoresSafeArea()
	22	ZStack {
	23	style.background.ignoresSafeArea()
17	24	if let scene = model.scene {
18	25	let view = current(width: geo.size.width)
19		SkyView(scene: scene, centerAzimuth: view.azimuth, centerAltitude: view.altitude, fieldOfView: view.fieldOfView) { [stats] d in
	26	SkyView(scene: scene, centerAzimuth: view.azimuth, centerAltitude: view.altitude, fieldOfView: view.fieldOfView, style: style) { [stats] d in
20	27	stats.record(d)
21	28	}
22	29	.ignoresSafeArea()
23	30	.gesture(panGesture(width: geo.size.width).simultaneously(with: zoomGesture))
	31	.onTapGesture(coordinateSpace: .local) { location in
	32	let p = Projection(centerAzimuth: view.azimuth, centerAltitude: view.altitude, fieldOfView: view.fieldOfView, size: geo.size)
	33	select(scene.object(at: location, projection: p))
	34	}
	35	}
	36	VStack(spacing: 0) {
	37	header
	38	Spacer()
	39	if let selection { card(for: selection).padding(.horizontal, 16).padding(.bottom, 10) }
	40	scrubber
24	41	}
25		header
26	42	}
27	43	}
	44	.foregroundStyle(ink)
	45	.onChange(of: model.offsetHours) { select(selection) }
28	46	.task {
29	47	model.start()
30	48	while !Task.isCancelled {
		@@ -34,6 +52,13 @@ struct SkyScreen: View {
34	52	}
35	53	}
36	54
	55	private func select(_ object: SkyObject?) {
	56	selection = object
	57	details = nil
	58	guard case .body(let body) = object else { return }
	59	Task { details = await model.details(of: body) }
	60	}
	61
37	62	/// The view direction with any in-progress gestures applied.
38	63	private func current(width: CGFloat) -> (azimuth: Double, altitude: Double, fieldOfView: Double) {
39	64	let fov = min(max(fieldOfView / Double(zoom), 30), 140)
		@@ -44,7 +69,7 @@ struct SkyScreen: View {
44	69	}
45	70
46	71	private func panGesture(width: CGFloat) -> some Gesture {
47		DragGesture(minimumDistance: 0)
	72	DragGesture(minimumDistance: 6)
48	73	.updating($drag) { value, state, _ in state = value.translation }
49	74	.onEnded { value in
50	75	let degreesPerPoint = fieldOfView / Double(max(width, 1))
		@@ -60,19 +85,104 @@ struct SkyScreen: View {
60	85	}
61	86
62	87	private var header: some View {
63		VStack(alignment: .leading, spacing: 4) {
64		Text("Tonight").font(.system(size: 22, weight: .medium))
65		Text(model.hasLocation ? "Your location" : "Chicago (location unavailable)")
66		.font(.system(size: 11)).foregroundStyle(.secondary)
67		TimelineView(.periodic(from: .now, by: 1)) { _ in
68		Text(stats.summary(build: model.lastBuild))
69		.font(.system(size: 10).monospacedDigit()).foregroundStyle(.secondary)
	88	HStack(alignment: .top) {
	89	VStack(alignment: .leading, spacing: 4) {
	90	Text(model.offsetHours == 0 ? "Tonight" : "Sky at \(model.displayedDate.formatted(date: .omitted, time: .shortened))")
	91	.font(.system(size: 22, weight: .medium))
	92	Text(model.hasLocation ? "Your location" : "Chicago (location unavailable)")
	93	.font(.system(size: 11)).opacity(0.7)
	94	TimelineView(.periodic(from: .now, by: 1)) { _ in
	95	Text(stats.summary(build: model.lastBuild))
	96	.font(.system(size: 10).monospacedDigit()).opacity(0.7)
	97	}
	98	}
	99	Spacer()
	100	Button {
	101	night.toggle()
	102	} label: {
	103	Image(systemName: night ? "eye.fill" : "eye")
	104	.font(.system(size: 17))
	105	.frame(width: 44, height: 44)
70	106	}
	107	.accessibilityLabel(night ? "Turn off night mode" : "Turn on night mode")
71	108	}
72		.foregroundStyle(Color(red: 0.95, green: 0.95, blue: 0.93))
73	109	.padding(.horizontal, 20)
74	110	.padding(.top, 8)
75	111	}
	112
	113	private var scrubber: some View {
	114	HStack(spacing: 12) {
	115	Text(model.displayedDate.formatted(date: .omitted, time: .shortened))
	116	.font(.system(size: 13).monospacedDigit())
	117	.frame(width: 70, alignment: .leading)
	118	Slider(value: $model.offsetHours, in: -12...12, step: 0.25)
	119	.tint(ink)
	120	Button("Now") { model.offsetHours = 0 }
	121	.font(.system(size: 13, weight: .medium))
	122	.disabled(model.offsetHours == 0)
	123	}
	124	.padding(.horizontal, 20)
	125	.padding(.vertical, 12)
	126	.background(style.ground.opacity(0.9))
	127	}
	128
	129	@ViewBuilder
	130	private func card(for object: SkyObject) -> some View {
	131	VStack(alignment: .leading, spacing: 8) {
	132	HStack {
	133	Text(title(for: object)).font(.system(size: 20, weight: .medium))
	134	Spacer()
	135	Button { selection = nil } label: { Image(systemName: "xmark").frame(width: 32, height: 32) }
	136	.accessibilityLabel("Close")
	137	}
	138	switch object {
	139	case .body:
	140	if let d = details { bodyFacts(d) } else { ProgressView().tint(ink) }
	141	case .constellation(let id):
	142	Text("Constellation · \(id)").font(.system(size: 13)).opacity(0.7)
	143	}
	144	}
	145	.padding(16)
	146	.background(style.background.opacity(0.92), in: .rect(cornerRadius: 12))
	147	.overlay(RoundedRectangle(cornerRadius: 12).stroke(ink.opacity(0.25), lineWidth: 0.5))
	148	}
	149
	150	private func title(for object: SkyObject) -> String {
	151	switch object {
	152	case .body(let b): b.rawValue.capitalized
	153	case .constellation(let id): constellationNames[id] ?? id
	154	}
	155	}
	156
	157	private func bodyFacts(_ d: BodyDetails) -> some View {
	158	let time: (Date?) -> String = { $0?.formatted(date: .omitted, time: .shortened) ?? "–" }
	159	let distance = d.body == .moon
	160	? "\(Int((d.distanceAU * 149_597_870.7).rounded()).formatted()) km"
	161	: String(format: "%.2f AU", d.distanceAU)
	162	let rows: [(String, String)] = [
	163	("Altitude", String(format: "%.0f°", d.position.altitude)),
	164	("Direction", String(format: "%.0f° %@", d.position.azimuth, compass(d.position.azimuth))),
	165	("Magnitude", String(format: "%.1f", d.magnitude)),
	166	(d.body == .moon ? "Illuminated" : "Phase", String(format: "%.0f%%", d.phaseFraction * 100)),
	167	("Distance", distance),
	168	("Next rise", time(d.rise)),
	169	("Next set", time(d.set)),
	170	]
	171	return Grid(alignment: .leading, horizontalSpacing: 16, verticalSpacing: 4) {
	172	ForEach(rows, id: \.0) { row in
	173	GridRow {
	174	Text(row.0).opacity(0.7)
	175	Text(row.1).monospacedDigit()
	176	}
	177	.font(.system(size: 13))
	178	}
	179	}
	180	}
	181
	182	private func compass(_ azimuth: Double) -> String {
	183	let points = ["N", "NE", "E", "SE", "S", "SW", "W", "NW"]
	184	return points[Int(((azimuth + 22.5) / 45).rounded(.down)) % 8]
	185	}
76	186	}
77	187
78	188	/// Draw timings for the debug readout. Written from the Canvas closure, read once a second.

Packages/MoonriseKit/Sources/SkyEngine/SkyEngine.swift +24

		@@ -122,6 +122,30 @@ public enum SkyEngine {
122	122	return Illumination(magnitude: i.mag, phaseFraction: i.phase_fraction)
123	123	}
124	124
	125	static func date(_ t: astro_time_t) -> Date {
	126	Date(timeIntervalSince1970: 946_728_000 + t.ut * 86_400)
	127	}
	128
	129	/// Next rise and next set within `limitDays` after `date`; nil if none in that window.
	130	public static func riseSet(_ body: Body, after date: Date, from observer: Observer, limitDays: Double = 1) -> (rise: Date?, set: Date?) {
	131	let t = time(date)
	132	let rise = Astronomy_SearchRiseSetEx(body.astro, observer.astro, DIRECTION_RISE, t, limitDays, 0)
	133	let set = Astronomy_SearchRiseSetEx(body.astro, observer.astro, DIRECTION_SET, t, limitDays, 0)
	134	return (rise.status == ASTRO_SUCCESS ? Self.date(rise.time) : nil,
	135	set.status == ASTRO_SUCCESS ? Self.date(set.time) : nil)
	136	}
	137
	138	public enum MoonQuarter: Int, Sendable {
	139	case new, firstQuarter, full, lastQuarter
	140	}
	141
	142	/// The first lunar quarter after `date`.
	143	public static func nextMoonQuarter(after date: Date) throws -> (quarter: MoonQuarter, date: Date) {
	144	let q = Astronomy_SearchMoonQuarter(time(date))
	145	try check(q.status)
	146	return (MoonQuarter(rawValue: Int(q.quarter))!, Self.date(q.time))
	147	}
	148
125	149	/// Moon's ecliptic longitude east of the sun in degrees: 0 new, 90 first quarter, 180 full, 270 last quarter.
126	150	public static func moonPhase(at date: Date) throws -> Double {
127	151	let a = Astronomy_MoonPhase(time(date))

Packages/MoonriseKit/Sources/SkyRenderer/ConstellationNames.swift added +21

		@@ -0,0 +1,21 @@
	1	/// IAU abbreviations to names.
	2	public let constellationNames: [String: String] = [
	3	"And": "Andromeda", "Ant": "Antlia", "Aps": "Apus", "Aqr": "Aquarius", "Aql": "Aquila",
	4	"Ara": "Ara", "Ari": "Aries", "Aur": "Auriga", "Boo": "Boötes", "Cae": "Caelum",
	5	"Cam": "Camelopardalis", "Cnc": "Cancer", "CVn": "Canes Venatici", "CMa": "Canis Major", "CMi": "Canis Minor",
	6	"Cap": "Capricornus", "Car": "Carina", "Cas": "Cassiopeia", "Cen": "Centaurus", "Cep": "Cepheus",
	7	"Cet": "Cetus", "Cha": "Chamaeleon", "Cir": "Circinus", "Col": "Columba", "Com": "Coma Berenices",
	8	"CrA": "Corona Australis", "CrB": "Corona Borealis", "Crv": "Corvus", "Crt": "Crater", "Cru": "Crux",
	9	"Cyg": "Cygnus", "Del": "Delphinus", "Dor": "Dorado", "Dra": "Draco", "Equ": "Equuleus",
	10	"Eri": "Eridanus", "For": "Fornax", "Gem": "Gemini", "Gru": "Grus", "Her": "Hercules",
	11	"Hor": "Horologium", "Hya": "Hydra", "Hyi": "Hydrus", "Ind": "Indus", "Lac": "Lacerta",
	12	"Leo": "Leo", "LMi": "Leo Minor", "Lep": "Lepus", "Lib": "Libra", "Lup": "Lupus",
	13	"Lyn": "Lynx", "Lyr": "Lyra", "Men": "Mensa", "Mic": "Microscopium", "Mon": "Monoceros",
	14	"Mus": "Musca", "Nor": "Norma", "Oct": "Octans", "Oph": "Ophiuchus", "Ori": "Orion",
	15	"Pav": "Pavo", "Peg": "Pegasus", "Per": "Perseus", "Phe": "Phoenix", "Pic": "Pictor",
	16	"Psc": "Pisces", "PsA": "Piscis Austrinus", "Pup": "Puppis", "Pyx": "Pyxis", "Ret": "Reticulum",
	17	"Sge": "Sagitta", "Sgr": "Sagittarius", "Sco": "Scorpius", "Scl": "Sculptor", "Sct": "Scutum",
	18	"Ser": "Serpens", "Sex": "Sextans", "Tau": "Taurus", "Tel": "Telescopium", "Tri": "Triangulum",
	19	"TrA": "Triangulum Australe", "Tuc": "Tucana", "UMa": "Ursa Major", "UMi": "Ursa Minor", "Vel": "Vela",
	20	"Vir": "Virgo", "Vol": "Volans", "Vul": "Vulpecula",
	21	]

Packages/MoonriseKit/Sources/SkyRenderer/HitTest.swift added +34

		@@ -0,0 +1,34 @@
	1	import CoreGraphics
	2	import SkyEngine
	3
	4	public enum SkyObject: Sendable, Equatable {
	5	case body(Body)
	6	/// IAU abbreviation.
	7	case constellation(String)
	8	}
	9
	10	extension SkyScene {
	11	/// The object under a tap: the nearest visible sun, moon or planet within
	12	/// `radius` points, else the constellation whose figure has a star nearest the tap.
	13	public func object(at point: CGPoint, projection p: Projection, radius: CGFloat = 28) -> SkyObject? {
	14	func distance(_ h: Horizontal) -> CGFloat? {
	15	guard h.altitude > 0, let q = p.point(h) else { return nil }
	16	return hypot(q.x - point.x, q.y - point.y)
	17	}
	18	let bodyHit = bodies
	19	.filter { $0.magnitude <= 6 }
	20	.compactMap { b in distance(b.position).map { (b.body, $0) } }
	21	.filter { $0.1 <= radius }
	22	.min { $0.1 < $1.1 }
	23	if let bodyHit { return .body(bodyHit.0) }
	24
	25	var best: (String, CGFloat)?
	26	for c in Catalog.constellations {
	27	for hr in c.lines.joined() {
	28	guard let h = starsByHR[hr], let d = distance(h), d <= radius * 1.5 else { continue }
	29	if best == nil \|\| d < best!.1 { best = (c.id, d) }
	30	}
	31	}
	32	return best.map { .constellation($0.0) }
	33	}
	34	}

Packages/MoonriseKit/Sources/SkyRenderer/SkyView.swift +24 −3

		@@ -39,11 +39,31 @@ public struct SkyStyle: Sendable {
39	39	public var muted = Color(red: 0.60, green: 0.64, blue: 0.70)
40	40	public var moonLight = Color(red: 0.93, green: 0.91, blue: 0.85)
41	41	public var moonDark = Color(red: 0.16, green: 0.20, blue: 0.27)
	42	public var planet = Color(red: 0.95, green: 0.84, blue: 0.60)
	43	/// Draw stars in a single red, for dark-adapted eyes.
	44	public var monochromeStars: Color?
42	45
43	46	public init() {}
44	47
	48	/// Red on black, to keep night vision.
	49	public static let night: SkyStyle = {
	50	var s = SkyStyle()
	51	let red = Color(red: 0.85, green: 0.12, blue: 0.08)
	52	s.background = .black
	53	s.ground = Color(red: 0.06, green: 0, blue: 0)
	54	s.line = red.opacity(0.35)
	55	s.label = red
	56	s.muted = red.opacity(0.7)
	57	s.moonLight = red
	58	s.moonDark = Color(red: 0.12, green: 0, blue: 0)
	59	s.planet = red
	60	s.monochromeStars = red
	61	return s
	62	}()
	63
45	64	/// Star tint from B−V colour index, kept pale.
46	65	func starColor(_ bv: Double) -> Color {
	66	if let monochromeStars { return monochromeStars }
47	67	let t = min(max((bv + 0.3) / 2.0, 0), 1)
48	68	return Color(red: 0.80 + 0.20 * t, green: 0.86 - 0.06 * t, blue: 1.0 - 0.32 * t)
49	69	}
		@@ -54,12 +74,13 @@ public struct SkyView: View {
54	74	public var centerAzimuth: Double
55	75	public var centerAltitude: Double
56	76	public var fieldOfView: Double
57		public var style = SkyStyle()
	77	public var style: SkyStyle
58	78	/// Called after each draw with the time the draw took.
59	79	public var onDraw: (@Sendable (Duration) -> Void)?
60	80
61		public init(scene: SkyScene, centerAzimuth: Double = 180, centerAltitude: Double = 55, fieldOfView: Double = 110, onDraw: (@Sendable (Duration) -> Void)? = nil) {
	81	public init(scene: SkyScene, centerAzimuth: Double = 180, centerAltitude: Double = 55, fieldOfView: Double = 110, style: SkyStyle = SkyStyle(), onDraw: (@Sendable (Duration) -> Void)? = nil) {
62	82	self.scene = scene
	83	self.style = style
63	84	self.centerAzimuth = centerAzimuth
64	85	self.centerAltitude = centerAltitude
65	86	self.fieldOfView = fieldOfView
		@@ -113,7 +134,7 @@ public struct SkyView: View {
113	134	label(&context, "Moon \(Int((b.phaseFraction * 100).rounded()))%", at: CGPoint(x: pt.x - 20, y: pt.y), anchor: .trailing)
114	135	} else {
115	136	let r = max(2.0, 3.6 - 0.35 * b.magnitude)
116		context.fill(Path(ellipseIn: CGRect(x: pt.x - r, y: pt.y - r, width: 2 * r, height: 2 * r)), with: .color(Color(red: 0.95, green: 0.84, blue: 0.60)))
	137	context.fill(Path(ellipseIn: CGRect(x: pt.x - r, y: pt.y - r, width: 2 * r, height: 2 * r)), with: .color(style.planet))
117	138	var tick = Path()
118	139	tick.move(to: CGPoint(x: pt.x + r + 3, y: pt.y))
119	140	tick.addLine(to: CGPoint(x: pt.x + r + 15, y: pt.y))

Packages/MoonriseKit/Tests/SkyEngineTests/EventTests.swift added +31

		@@ -0,0 +1,31 @@
	1	import Foundation
	2	import Testing
	3	@testable import SkyEngine
	4
	5	// Rise and set times from JPL Horizons (R_T_S_ONLY=TVH, refracted, minute resolution),
	6	// Chicago, searching 2026-10-17 00:00 to 2026-10-18 00:00 UT.
	7
	8	let midnightUT = Date(timeIntervalSince1970: 1_792_195_200) // 2026-10-17T00:00:00Z
	9
	10	func ut(_ hour: Int, _ minute: Int) -> Date {
	11	midnightUT.addingTimeInterval(TimeInterval(hour * 3600 + minute * 60))
	12	}
	13
	14	@Test(arguments: [
	15	(Body.sun, ut(12, 6), ut(23, 6)),
	16	(Body.saturn, ut(22, 39), ut(10, 58)),
	17	(Body.moon, ut(18, 57), ut(2, 49)),
	18	])
	19	func riseSetMatchesHorizons(_ body: Body, _ rise: Date, _ set: Date) throws {
	20	let r = SkyEngine.riseSet(body, after: midnightUT, from: chicago)
	21	let gotRise = try #require(r.rise)
	22	let gotSet = try #require(r.set)
	23	#expect(abs(gotRise.timeIntervalSince(rise)) < 120, "\(body) rise \(gotRise)")
	24	#expect(abs(gotSet.timeIntervalSince(set)) < 120, "\(body) set \(gotSet)")
	25	}
	26
	27	@Test func nextQuarterAfterObservationIsFirstQuarter() throws {
	28	let q = try SkyEngine.nextMoonQuarter(after: observed)
	29	#expect(q.quarter == .firstQuarter)
	30	#expect(q.date > observed && q.date < observed.addingTimeInterval(4 * 86_400))
	31	}

Packages/MoonriseKit/Tests/SkyRendererTests/SkyRenderTests.swift +20

		@@ -42,3 +42,23 @@ let evening = Date(timeIntervalSince1970: 1_792_202_400) // 2026-10-17T02:00:00Z
42	42	#expect(CGImageDestinationFinalize(dest))
43	43	}
44	44	}
	45
	46	@Test func tapOnSaturnFindsSaturnAndNearbyStarsFindTheirConstellation() throws {
	47	let scene = try SkyScene(date: evening, observer: chicago)
	48	let p = Projection(centerAzimuth: 180, centerAltitude: 45, fieldOfView: 100, size: CGSize(width: 393, height: 852))
	49	let saturn = try #require(scene.bodies.first { $0.body == .saturn })
	50	let pt = try #require(p.point(saturn.position))
	51	#expect(scene.object(at: CGPoint(x: pt.x + 5, y: pt.y), projection: p) == .body(.saturn))
	52
	53	// Altair (HR 7557) is in Aquila's figure.
	54	let altair = try #require(scene.starsByHR[7557])
	55	let a = try #require(p.point(altair))
	56	#expect(scene.object(at: a, projection: p) == .constellation("Aql"))
	57	}
	58
	59	@MainActor
	60	@Test func nightStyleRenders() throws {
	61	let scene = try SkyScene(date: evening, observer: chicago)
	62	let renderer = ImageRenderer(content: SkyView(scene: scene, style: .night).frame(width: 393, height: 852))
	63	#expect(renderer.cgImage != nil)
	64	}