Fix solar chart to use variable amplitude instead of moving horizon

Localizable.xcstrings

@@ -311,6 +311,9 @@
           }
         }
       }
+    },
+    "Altitude" : {
+
     },
     "Appearance" : {
       "localizations" : {

Solstice.xcodeproj/project.pbxproj

@@ -1809,7 +1809,7 @@
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				INFOPLIST_KEY_NSLocationWhenInUseUsageDescription = "Solstice uses your location to calculate local sunrise and sunset times";
 				LOCALIZATION_PREFERS_STRING_CATALOGS = YES;
-				MARKETING_VERSION = 3.1;
+				MARKETING_VERSION = 3.1.1;
 				MTL_ENABLE_DEBUG_INFO = INCLUDE_SOURCE;
 				MTL_FAST_MATH = YES;
 				ONLY_ACTIVE_ARCH = YES;
@@ -1871,7 +1871,7 @@
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				INFOPLIST_KEY_NSLocationWhenInUseUsageDescription = "Solstice uses your location to calculate local sunrise and sunset times";
 				LOCALIZATION_PREFERS_STRING_CATALOGS = YES;
-				MARKETING_VERSION = 3.1;
+				MARKETING_VERSION = 3.1.1;
 				MTL_ENABLE_DEBUG_INFO = NO;
 				MTL_FAST_MATH = YES;
 				SDKROOT = iphoneos;

Solstice.xcodeproj/xcuserdata/dte.xcuserdatad/xcdebugger/Breakpoints_v2.xcbkptlist

@@ -3,52 +3,4 @@
    uuid = "694A27F2-72FC-45F0-A4E5-28318A89FE23"
    type = "1"
    version = "2.0">
-   <Breakpoints>
-      <BreakpointProxy
-         BreakpointExtensionID = "Xcode.Breakpoint.FileBreakpoint">
-         <BreakpointContent
-            uuid = "D80AA32B-93C1-4B79-8BCD-7882590E25ED"
-            shouldBeEnabled = "Yes"
-            ignoreCount = "0"
-            continueAfterRunningActions = "No"
-            filePath = "Solstice/Helpers/DeepLinkResolver.swift"
-            startingColumnNumber = "9223372036854775807"
-            endingColumnNumber = "9223372036854775807"
-            startingLineNumber = "58"
-            endingLineNumber = "58"
-            landmarkName = "body(content:)"
-            landmarkType = "7">
-            <Locations>
-               <Location
-                  uuid = "D80AA32B-93C1-4B79-8BCD-7882590E25ED - 87f91cbc3384d0c9"
-                  shouldBeEnabled = "Yes"
-                  ignoreCount = "0"
-                  continueAfterRunningActions = "No"
-                  symbolName = "closure #1 (Foundation.URL) -&gt; () in Solstice.DeepLinkResolver.body(content: SwiftUI._ViewModifier_Content&lt;Solstice.DeepLinkResolver&gt;) -&gt; some"
-                  moduleName = "Solstice.debug.dylib"
-                  usesParentBreakpointCondition = "Yes"
-                  urlString = "file:///Users/dte/Developer/Solstice/Solstice/Helpers/DeepLinkResolver.swift"
-                  startingColumnNumber = "9223372036854775807"
-                  endingColumnNumber = "9223372036854775807"
-                  startingLineNumber = "58"
-                  endingLineNumber = "58">
-               </Location>
-               <Location
-                  uuid = "D80AA32B-93C1-4B79-8BCD-7882590E25ED - 24c23c16d8a7bd00"
-                  shouldBeEnabled = "Yes"
-                  ignoreCount = "0"
-                  continueAfterRunningActions = "No"
-                  symbolName = "closure #1 (Foundation.URL) -&gt; () in Solstice_watchOS_Watch_App.DeepLinkResolver.body(content: SwiftUI._ViewModifier_Content&lt;Solstice_watchOS_Watch_App.DeepLinkResolver&gt;) -&gt; some"
-                  moduleName = "Solstice watchOS Watch App.debug.dylib"
-                  usesParentBreakpointCondition = "Yes"
-                  urlString = "file:///Users/dte/Developer/Solstice/Solstice/Helpers/DeepLinkResolver.swift"
-                  startingColumnNumber = "9223372036854775807"
-                  endingColumnNumber = "9223372036854775807"
-                  startingLineNumber = "58"
-                  endingLineNumber = "58">
-               </Location>
-            </Locations>
-         </BreakpointContent>
-      </BreakpointProxy>
-   </Breakpoints>
 </Bucket>

Solstice/Charts/DaylightChart.swift

@@ -12,21 +12,21 @@ import Suite
 struct DaylightChart: View {
 	@Environment(\.isLuminanceReduced) var isLuminanceReduced
 	@Environment(\.colorScheme) var colorScheme
-	
+
 	@State private var selectedEvent: NTSolar.Event?
 	@State private var currentX: Date?
-	
+
 	var solar: NTSolar
 	var timeZone: TimeZone
 	var showEventTypes = true
-	
+
 	var appearance = Appearance.simple
 	var includesSummaryTitle = true
 	var hideXAxis = false
 	var scrubbable = false
 	var markSize: CGFloat = 6
-	var yScale = -1.5...1.5
-	
+	var yScale: ClosedRange<Double>? = nil
+
 	var plotDate: Date {
 		currentX ?? solar.date
 	}
@@ -81,12 +81,23 @@ struct DaylightChart: View {
 
 	private var chartContent: some View {
 		Chart {
+			ForEach(hours, id: \.self) { hour in
+				LineMark(
+					x: .value("Time", hour),
+					y: .value("Altitude", yValue(for: hour))
+				)
+				.interpolationMethod(.catmullRom)
+				.foregroundStyle(solarPathGradient)
+				.lineStyle(StrokeStyle(lineWidth: markSize, lineCap: .round, lineJoin: .round))
+			}
+
 			ForEach(filteredEvents, id: \.id) { solarEvent in
 				eventPointMark(for: solarEvent)
 			}
 		}
+		.chartLegend(.hidden)
 		.chartYAxis(.hidden)
-		.chartYScale(domain: yScale)
+		.chartYScale(domain: effectiveYScale)
 		.chartXAxis(hideXAxis ? .hidden : .automatic)
 		.chartXAxis {
 			if !hideXAxis {
@@ -103,9 +114,7 @@ struct DaylightChart: View {
 				chartOverlayContent(proxy: proxy, geo: geo)
 			}
 		}
-		.chartBackground { proxy in
-			solarPathView(proxy: proxy)
-		}
+		.animation(nil, value: solar.date)
 	}
 
 	private var filteredEvents: [NTSolar.Event] {
@@ -130,7 +139,7 @@ struct DaylightChart: View {
 
 	@ViewBuilder
 	private func chartOverlayContent(proxy: ChartProxy, geo: GeometryProxy) -> some View {
-		let horizonY: CGFloat = proxy.position(forY: yValue(for: solar.safeSunrise)) ?? 0
+		let horizonY: CGFloat = proxy.position(forY: 0.0) ?? 0
 
 		Group {
 			horizonLine(width: geo.size.width, yOffset: horizonY)
@@ -141,6 +150,7 @@ struct DaylightChart: View {
 				sunAboveHorizon(proxy: proxy, horizonY: horizonY)
 			}
 		}
+		.animation(nil, value: solar.date)
 
 		scrubHitArea(geo: geo, proxy: proxy)
 	}
@@ -248,30 +258,6 @@ struct DaylightChart: View {
 			}
 	}
 
-	private func solarPathView(proxy: ChartProxy) -> some View {
-		Path { path in
-			if let firstPoint = hours.first,
-				 let x = proxy.position(forX: firstPoint),
-				 let y = proxy.position(forY: yValue(for: firstPoint)) {
-				path.move(to: CGPoint(x: x, y: y))
-			}
-
-			hours.forEach { hour in
-				let x: CGFloat = proxy.position(forX: hour) ?? 0
-				let y: CGFloat = proxy.position(forY: yValue(for: hour)) ?? 0
-				path.addLine(to: CGPoint(x: x, y: y))
-			}
-
-			if let lastPoint = hours.last,
-				 let x = proxy.position(forX: lastPoint),
-				 let y = proxy.position(forY: yValue(for: lastPoint)) {
-				path.move(to: CGPoint(x: x, y: y))
-			}
-		}
-		.strokedPath(StrokeStyle(lineWidth: markSize, lineCap: .round, lineJoin: .round))
-		.fill(solarPathGradient)
-	}
-
 	private var solarPathGradient: LinearGradient {
 		LinearGradient(stops: [
 			Gradient.Stop(color: .secondary.opacity(0), location: 0),
@@ -285,19 +271,9 @@ extension DaylightChart {
 	var hours: Array<Date> {
 		stride(from: range.lowerBound, through: range.upperBound, by: 60 * 30).compactMap { $0 }
 	}
-	
+
 	var startOfDay: Date { range.lowerBound }
-	var endOfDay: Date { range.upperBound }
-	var dayLength: TimeInterval { .twentyFourHours }
-
-	var noonish: Date { startOfDay.addingTimeInterval(TimeInterval.twentyFourHours / 2) }
-
-	var culminationDelta: TimeInterval { solar.solarNoon?.distance(to: noonish) ?? 0 }
-
-	var daylightProportion: Double {
-		solar.daylightDuration / dayLength
-	}
-
+
 	func pointMarkColor(for eventPhase: NTSolar.Phase) -> HierarchicalShapeStyle {
 		switch eventPhase {
 		case .astronomical:
@@ -310,23 +286,35 @@ extension DaylightChart {
 			return .primary
 		}
 	}
-	
+
 	func resetSelectedEvent() {
 		selectedEvent = solar.events.filter {
 			$0.phase == .sunset || $0.phase == .sunrise
 		}.sorted(by: { a, b in
 			a.date.compare(.now) == .orderedDescending
 		}).first
 	}
-
-	func progressValue(for date: Date) -> Double {
-		return (date.distance(to: startOfDay) - culminationDelta) / dayLength
+
+	/// The y-scale to use for the chart, fitted to the actual min/max altitudes
+	/// across all sampled hours with padding so the path never crowds the edges.
+	/// Callers may override via the `yScale` property.
+	private var effectiveYScale: ClosedRange<Double> {
+		if let yScale { return yScale }
+		let altitudes = hours.map { yValue(for: $0) }
+		guard let minAlt = altitudes.min(), let maxAlt = altitudes.max() else {
+			return -90.0...90.0
+		}
+		let span = maxAlt - minAlt
+		let padding = span * 0.1
+		return (minAlt - padding)...(maxAlt + padding)
 	}
-
+
+	/// The sun's actual altitude in degrees at `date` for the current solar.
+	/// 0° is the geometric horizon; positive = above, negative = below.
 	func yValue(for date: Date) -> Double {
-		return sin(progressValue(for: date) * .pi * 2 - .pi / 2)
+		solar.altitude(at: date)
 	}
-	
+
 	func scrub(to point: CGPoint, in geo: GeometryProxy, proxy: ChartProxy) {
 		var start: Double = 0
 

Solstice/Detail View/DailyOverview.swift

@@ -95,9 +95,6 @@ struct DailyOverview<Location: AnyLocation>: View {
 					.background(Color("listRowBackgroundColor"))
 			)
 			#endif
-			#if !os(macOS)
-			.menuActionDismissBehavior(.disabled)
-			#endif
 			#endif
 
 			Group {

Solstice/Extensions/AppStorage++.swift

@@ -137,6 +137,7 @@ struct Preferences {
 	static let timeTravelAppearance: Value<TimeTravelAppearance> = ("timeTravelAppearance", .expanded)
 
 	static let chartType: Value<ChartType> = ("chartType", .classic)
+	static let showSolsticesInChart: Value<Bool> = ("showSolsticesInChart", false)
 }
 
 enum TimeTravelAppearance: String, CaseIterable, RawRepresentable, Identifiable {

Solstice/Helpers/Globals.swift

@@ -9,7 +9,7 @@ import Foundation
 
 var chartHeight: CGFloat = {
 #if !os(watchOS)
-	300
+	360
 #else
 	200
 #endif
@@ -19,7 +19,7 @@ var chartMarkSize: Double = {
 #if os(watchOS)
 	4
 #else
-	8
+	6
 #endif
 }()
 

Solstice/Helpers/NTSolar.swift

@@ -679,3 +679,40 @@ struct NTSolar {
     }  /* GMST0 */
 
 }
+
+extension NTSolar {
+	/// Returns the sun's altitude above the horizon in degrees at the given instant.
+	/// Positive values are above the horizon, negative values are below.
+	///
+	/// Uses the same astronomical algorithms as the rest of NTSolar (Schlyter's
+	/// method), so results are consistent with the sunrise/sunset times already
+	/// computed by this struct.
+	func altitude(at date: Date) -> Double {
+		var utcCal = Calendar(identifier: .gregorian)
+		utcCal.timeZone = TimeZone(secondsFromGMT: 0)!
+		let comps = utcCal.dateComponents([.year, .month, .day, .hour, .minute, .second], from: date)
+		guard let year = comps.year, let month = comps.month, let day = comps.day,
+			  let hour = comps.hour, let minute = comps.minute, let second = comps.second
+		else { return 0 }
+
+		// UT as a decimal hour
+		let UT = Double(hour) + Double(minute) / 60.0 + Double(second) / 3600.0
+
+		// Days since J2000.0 at the exact instant (used for both sun position and sidereal time)
+		let d = Double(NTSolar.days_since_2000_Jan_0(y: year, m: month, d: day)) + UT / 24.0
+
+		// Sun's equatorial coordinates at this instant
+		let (sRA, sdec, _) = NTSolar.sun_RA_dec(d: d)
+
+		// Local Mean Sidereal Time in degrees: GMST0(d) + UT_in_degrees + longitude
+		let LMST = NTSolar.revolution(x: NTSolar.GMST0(d: d) + UT * 15.0 + coordinate.longitude)
+
+		// Local Hour Angle: how far the sun has moved past the meridian
+		let HA = LMST - sRA
+
+		// Standard altitude formula: sin(alt) = sin(lat)sin(dec) + cos(lat)cos(dec)cos(HA)
+		let sin_alt = NTSolar.sind(x: coordinate.latitude) * NTSolar.sind(x: sdec)
+			+ NTSolar.cosd(x: coordinate.latitude) * NTSolar.cosd(x: sdec) * NTSolar.cosd(x: HA)
+		return NTSolar.asind(x: sin_alt)
+	}
+}

Widget/Solar Chart Widget/SolarChartWidgetView.swift

@@ -44,8 +44,7 @@ struct SolarChartWidgetView: SolsticeWidgetView {
 						timeZone: location.timeZone,
 						showEventTypes: false,
 						includesSummaryTitle: false,
-						markSize: 3,
-						yScale: -1.0...1.5
+						markSize: 3
 					)
 				}
 			} else if needsReconfiguration {