Honor preview moon travel direction and bump mobile to v1.1.11

CHANGELOG.md

@@ -5,6 +5,13 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [1.1.11] — 2026-02-22
+
+### Fixed
+- Updated preview mode moon motion so left/right travel direction follows local contact bearing progression when bearing data is available.
+- Wired contact bearing values into preview payload construction so direction-aware geometry has access to C1/C2/C3/C4 bearing inputs.
+- Added regression tests for bearing-based travel direction selection and fallback behavior when bearing pairs are incomplete.
+
 ## [1.1.10] — 2026-02-22
 
 ### Fixed

apps/mobile/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@eclipse-timer/mobile",
-  "version": "1.1.10",
+  "version": "1.1.11",
   "private": true,
   "main": "index.js",
   "scripts": {

apps/mobile/src/navigation/RootNavigator.tsx

@@ -353,6 +353,10 @@ function TimerRoute({ navigation, catalog, onOpenMenu }: TimerRouteProps) {
         maxUtc: result.maxUtc,
         c3Utc: result.c3Utc,
         c4Utc: result.c4Utc,
+        c1BearingDeg: result.c1BearingDeg,
+        c2BearingDeg: result.c2BearingDeg,
+        c3BearingDeg: result.c3BearingDeg,
+        c4BearingDeg: result.c4BearingDeg,
       };
 
       navigation.navigate("Preview", { payload });

apps/mobile/src/screens/EclipsePreviewScreen.tsx

@@ -16,6 +16,7 @@ import { colorForContactKey } from "../utils/contactTheme";
 import { fmtLocalHuman, fmtUtcHuman } from "../utils/date";
 import {
   calculatePreviewMoonGeometry,
+  determinePreviewTravelDirection,
   PREVIEW_STAGE_SIZE,
   PREVIEW_SUN_RADIUS,
 } from "../utils/previewGeometry";
@@ -46,6 +47,10 @@ export type PreviewPayload = {
   maxUtc?: string;
   c3Utc?: string;
   c4Utc?: string;
+  c1BearingDeg?: number;
+  c2BearingDeg?: number;
+  c3BearingDeg?: number;
+  c4BearingDeg?: number;
 };
 
 type EclipsePreviewScreenProps = {
@@ -310,8 +315,23 @@ export default function EclipsePreviewScreen({
         contacts: contactProgress,
         stageSize: SIM_STAGE_SIZE,
         sunRadius: SUN_RADIUS,
+        travelDirection: determinePreviewTravelDirection({
+          c1BearingDeg: payload.c1BearingDeg,
+          c2BearingDeg: payload.c2BearingDeg,
+          c3BearingDeg: payload.c3BearingDeg,
+          c4BearingDeg: payload.c4BearingDeg,
+        }),
       }),
-    [contactProgress, payload.kindAtLocation, payload.magnitude, progress],
+    [
+      contactProgress,
+      payload.c1BearingDeg,
+      payload.c2BearingDeg,
+      payload.c3BearingDeg,
+      payload.c4BearingDeg,
+      payload.kindAtLocation,
+      payload.magnitude,
+      progress,
+    ],
   );
 
   const phaseLabel = useMemo(

apps/mobile/src/utils/previewGeometry.ts

@@ -20,10 +20,49 @@ export type PreviewMoonGeometry = {
   moonTravelHalfSpan: number;
 };
 
+export type PreviewDirectionBearings = {
+  c1BearingDeg?: number;
+  c2BearingDeg?: number;
+  c3BearingDeg?: number;
+  c4BearingDeg?: number;
+};
+
 function clamp01(v: number) {
   return Math.max(0, Math.min(1, v));
 }
 
+function normalizeSignedDeltaDeg(fromDeg: number, toDeg: number) {
+  const delta = ((toDeg - fromDeg + 540) % 360) - 180;
+  return delta === -180 ? 180 : delta;
+}
+
+function resolveDirectionalBearingPair(bearings: PreviewDirectionBearings) {
+  const pairs: Array<[number | undefined, number | undefined]> = [
+    [bearings.c1BearingDeg, bearings.c4BearingDeg],
+    [bearings.c2BearingDeg, bearings.c3BearingDeg],
+    [bearings.c1BearingDeg, bearings.c3BearingDeg],
+    [bearings.c2BearingDeg, bearings.c4BearingDeg],
+  ];
+
+  for (const [start, end] of pairs) {
+    if (typeof start !== "number" || !Number.isFinite(start)) continue;
+    if (typeof end !== "number" || !Number.isFinite(end)) continue;
+    return { start, end };
+  }
+
+  return null;
+}
+
+export function determinePreviewTravelDirection(
+  bearings: PreviewDirectionBearings | undefined,
+): 1 | -1 {
+  if (!bearings) return 1;
+  const pair = resolveDirectionalBearingPair(bearings);
+  if (!pair) return 1;
+  const delta = normalizeSignedDeltaDeg(pair.start, pair.end);
+  return delta >= 0 ? 1 : -1;
+}
+
 export function determineMoonRadius(kindAtLocation: EclipseKindAtLocation) {
   if (kindAtLocation === "annular") return 58;
   if (kindAtLocation === "total") return 76;
@@ -109,6 +148,7 @@ export function calculatePreviewMoonGeometry(params: {
   contacts?: PreviewMotionContacts;
   stageSize?: number;
   sunRadius?: number;
+  travelDirection?: 1 | -1;
 }): PreviewMoonGeometry {
   const stageSize = params.stageSize ?? PREVIEW_STAGE_SIZE;
   const sunRadius = params.sunRadius ?? PREVIEW_SUN_RADIUS;
@@ -121,7 +161,8 @@ export function calculatePreviewMoonGeometry(params: {
   );
 
   const anchors = buildMotionAnchors(params.contacts ?? {}, sunRadius, moonRadius);
-  const moonOffsetX = interpolateOffsetX(params.progress, anchors);
+  const travelDirection = params.travelDirection ?? 1;
+  const moonOffsetX = interpolateOffsetX(params.progress, anchors) * travelDirection;
   const moonCenterX = stageSize / 2 + moonOffsetX;
   const moonCenterY = stageSize / 2 + moonClosestOffset;
 

apps/mobile/tests/preview-geometry.test.ts

@@ -1,6 +1,10 @@
 import { describe, expect, it } from "vitest";
 
-import { calculatePreviewMoonGeometry, PREVIEW_SUN_RADIUS } from "../src/utils/previewGeometry";
+import {
+  calculatePreviewMoonGeometry,
+  determinePreviewTravelDirection,
+  PREVIEW_SUN_RADIUS,
+} from "../src/utils/previewGeometry";
 
 describe("preview moon geometry", () => {
   it("places C1 at exact outer tangency", () => {
@@ -49,4 +53,39 @@ describe("preview moon geometry", () => {
     expect(c3Distance).toBeCloseTo(Math.abs(PREVIEW_SUN_RADIUS - c3Geometry.moonRadius), 6);
     expect(postC3Distance).toBeGreaterThan(c3Distance);
   });
+
+  it("uses contact bearings to keep moon travel direction accurate", () => {
+    const leftToRightDirection = determinePreviewTravelDirection({
+      c1BearingDeg: 100,
+      c4BearingDeg: 140,
+    });
+    const rightToLeftDirection = determinePreviewTravelDirection({
+      c1BearingDeg: 140,
+      c4BearingDeg: 100,
+    });
+
+    const baseParams = {
+      progress: 0.25,
+      kindAtLocation: "total" as const,
+      contacts: { c1: 0, c2: 0.25, max: 0.5, c3: 0.75, c4: 1 },
+    };
+
+    const leftToRight = calculatePreviewMoonGeometry({
+      ...baseParams,
+      travelDirection: leftToRightDirection,
+    });
+    const rightToLeft = calculatePreviewMoonGeometry({
+      ...baseParams,
+      travelDirection: rightToLeftDirection,
+    });
+
+    expect(leftToRight.moonOffsetX).toBeLessThan(0);
+    expect(rightToLeft.moonOffsetX).toBeGreaterThan(0);
+    expect(Math.abs(leftToRight.moonOffsetX)).toBeCloseTo(Math.abs(rightToLeft.moonOffsetX), 6);
+  });
+
+  it("falls back to default travel direction when bearings are missing", () => {
+    expect(determinePreviewTravelDirection(undefined)).toBe(1);
+    expect(determinePreviewTravelDirection({ c2BearingDeg: 120 })).toBe(1);
+  });
 });