perf(web): reconcile fleet map incrementally

vehicle-data-platform/apps/web/src/integrations/amap.ts

@@ -39,6 +39,7 @@ export type AMapMassMarks = {
 export type AMapLabelsLayer = {
   setMap: (map: AMapMap | null) => void;
   add: (markers: AMapOverlay | AMapOverlay[]) => void;
+  remove: (markers: AMapOverlay | AMapOverlay[]) => void;
   clear: () => void;
 };
 

vehicle-data-platform/apps/web/src/v2/map/FleetMap.test.tsx

@@ -7,6 +7,7 @@ import { FleetMap } from './FleetMap';
 const setData = vi.fn<(data: AMapMassPoint[]) => void>();
 const setStyle = vi.fn();
 const addLabels = vi.fn();
+const removeLabels = vi.fn();
 const clearLabels = vi.fn();
 const setLabelsMap = vi.fn();
 const markerSetMap = vi.fn();
@@ -55,6 +56,7 @@ class TestLabelsLayer {
     labelLayerOptions.push(options);
   }
   add = addLabels;
+  remove = removeLabels;
   clear = clearLabels;
   setMap = setLabelsMap;
 }
@@ -144,6 +146,7 @@ afterEach(() => {
   setData.mockReset();
   setStyle.mockReset();
   addLabels.mockReset();
+  removeLabels.mockReset();
   clearLabels.mockReset();
   setLabelsMap.mockReset();
   markerSetMap.mockReset();
@@ -210,6 +213,41 @@ test('detaches AMap listeners and destroys the map on unmount', async () => {
   expect(mapDestroy).toHaveBeenCalledTimes(1);
 });
 
+test('skips unchanged refresh redraws and replaces only a moved vehicle label', async () => {
+  window.__LINGNIU_APP_CONFIG__ = { amapWebJsKey: 'amap-web-key' };
+  window.AMapLoader = { load: vi.fn(async () => amapMock()) };
+  const view = render(<FleetMap vehicles={[]} monitorMap={pointMap} onSelect={() => undefined} />);
+  await waitFor(() => expect(addLabels).toHaveBeenCalled());
+  const dataCalls = setData.mock.calls.length;
+  const styleCalls = setStyle.mock.calls.length;
+  const addCalls = addLabels.mock.calls.length;
+  const removeCalls = removeLabels.mock.calls.length;
+  const clearCalls = clearLabels.mock.calls.length;
+
+  await act(async () => {
+    view.rerender(<FleetMap vehicles={[]} monitorMap={{ ...pointMap, asOf: '2026-07-14T01:00:15Z' }} onSelect={() => undefined} />);
+    await Promise.resolve();
+  });
+  expect(setData).toHaveBeenCalledTimes(dataCalls);
+  expect(setStyle).toHaveBeenCalledTimes(styleCalls);
+  expect(addLabels).toHaveBeenCalledTimes(addCalls);
+  expect(removeLabels).toHaveBeenCalledTimes(removeCalls);
+  expect(clearLabels).toHaveBeenCalledTimes(clearCalls);
+
+  view.rerender(<FleetMap vehicles={[]} monitorMap={{
+    ...pointMap,
+    asOf: '2026-07-14T01:00:30Z',
+    points: [{ ...pointMap.points[0], longitude: 113.27 }, pointMap.points[1]]
+  }} onSelect={() => undefined} />);
+  await waitFor(() => expect(setData).toHaveBeenCalledTimes(dataCalls + 1));
+  expect(setStyle).toHaveBeenCalledTimes(styleCalls);
+  expect(removeLabels).toHaveBeenCalledTimes(removeCalls + 1);
+  expect(addLabels).toHaveBeenCalledTimes(addCalls + 1);
+  const replacementLabels = addLabels.mock.calls[addLabels.mock.calls.length - 1]?.[0] as TestLabelMarker[];
+  expect(replacementLabels).toHaveLength(1);
+  expect((replacementLabels[0].options.text as { content: string }).content).toBe('粤A12345');
+});
+
 test('converts AMap GCJ-02 bounds back to WGS-84 before requesting monitor data', async () => {
   const [west, south] = wgs84ToGcj02(113, 22);
   const [east, north] = wgs84ToGcj02(114, 24);
@@ -334,10 +372,10 @@ test('renders one selected plate and smoothly follows it until the map is dragge
   expect(toggle).toHaveAttribute('aria-pressed', 'true');
   fireEvent.click(toggle);
   await waitFor(() => expect(toggle).toHaveAttribute('aria-pressed', 'false'));
-  expect(clearLabels).toHaveBeenCalled();
+  expect(removeLabels).toHaveBeenCalled();
-  const selectedOnlyLabels = addLabels.mock.calls[addLabels.mock.calls.length - 1]?.[0] as TestLabelMarker[];
+  const hiddenFloatingLabels = removeLabels.mock.calls[removeLabels.mock.calls.length - 1]?.[0] as TestLabelMarker[];
-  expect(selectedOnlyLabels).toHaveLength(1);
+  expect(hiddenFloatingLabels).toHaveLength(1);
-  expect((selectedOnlyLabels[0].options.text as { content: string }).content).toBe('粤B67890');
+  expect((hiddenFloatingLabels[0].options.text as { content: string }).content).toBe('粤A12345');
 });
 
 test('renders every nearby plate with staggered positions at maximum zoom', async () => {
@@ -369,6 +407,7 @@ test('renders every nearby plate with staggered positions at maximum zoom', asyn
   view.rerender(<FleetMap vehicles={[]} monitorMap={crowdedMap} selectedVin="LTEST000000000002" onSelect={() => undefined} />);
   await waitFor(() => expect(addLabels.mock.calls.length).toBeGreaterThan(labelRenderCount));
   const selectedDenseMarkers = addLabels.mock.calls[addLabels.mock.calls.length - 1]?.[0] as TestLabelMarker[];
+  expect(selectedDenseMarkers).toHaveLength(1);
   expect(selectedDenseMarkers.every((marker) => marker.options.icon == null)).toBe(true);
   expect(selectedDenseMarkers.find((marker) => marker.options.rank === 100)).toBeDefined();
 });

vehicle-data-platform/apps/web/src/v2/map/FleetMap.tsx

@@ -85,6 +85,24 @@ type PlateLabelPoint = {
   latitude: number;
 };
 
+type LabelMarkerEntry = {
+  marker: AMapOverlay;
+  signature: string;
+};
+
+function massPointSignature(monitorMap: MonitorMapResponse | undefined, points: VehicleRealtimeRow[]) {
+  if (monitorMap) return [
+    `mode:${monitorMap.mode}`,
+    ...monitorMap.clusters.map((cluster) => `c:${cluster.id}:${cluster.longitude}:${cluster.latitude}:${cluster.count}`),
+    ...monitorMap.points.map((point) => `p:${point.vin}:${point.longitude}:${point.latitude}:${point.status}:${point.plate || ''}`)
+  ].join('|');
+  return ['vehicles', ...points.map((point) => `p:${point.vin}:${point.longitude}:${point.latitude}:${vehicleStatus(point)}:${point.plate || ''}`)].join('|');
+}
+
+function labelMarkerSignature(point: PlateLabelPoint, selected: boolean, placement?: { direction: 'left' | 'right'; textOffset: [number, number] }) {
+  return `${point.longitude}:${point.latitude}:${point.plate || point.vin}:${selected ? 1 : 0}:${placement?.direction ?? 'right'}:${placement?.textOffset.join(',') ?? '8,0'}`;
+}
+
 function densePlatePlacements(points: PlateLabelPoint[]) {
   const buckets = new Map<string, PlateLabelPoint[]>();
   for (const point of points) {
@@ -128,6 +146,11 @@ export function FleetMap({ vehicles, selectedVin, onSelect, monitorMap, onSelect
   const labelsRef = useRef<AMapLabelsLayer | null>(null);
   const denseLabelsRef = useRef<AMapLabelsLayer | null>(null);
   const selectionRef = useRef<AMapOverlay | null>(null);
+  const labelMarkersRef = useRef(new Map<string, LabelMarkerEntry>());
+  const labelLayerModeRef = useRef<'normal' | 'dense' | ''>('');
+  const labelLayerStateRef = useRef('');
+  const massDataSignatureRef = useRef('__unset__');
+  const massStyleSignatureRef = useRef('__unset__');
   const onSelectRef = useRef(onSelect);
   const onSelectVinRef = useRef(onSelectVin);
   const onViewportChangeRef = useRef(onViewportChange);
@@ -262,6 +285,8 @@ export function FleetMap({ vehicles, selectedVin, onSelect, monitorMap, onSelect
       }
       if (stopFollowing) mapInstance?.off?.('dragstart', stopFollowing);
       massRef.current?.setMap(null);
+      labelsRef.current?.clear();
+      denseLabelsRef.current?.clear();
       labelsRef.current?.setMap(null);
       denseLabelsRef.current?.setMap(null);
       selectionRef.current?.setMap?.(null);
@@ -270,6 +295,11 @@ export function FleetMap({ vehicles, selectedVin, onSelect, monitorMap, onSelect
       labelsRef.current = null;
       denseLabelsRef.current = null;
       selectionRef.current = null;
+      labelMarkersRef.current.clear();
+      labelLayerModeRef.current = '';
+      labelLayerStateRef.current = '';
+      massDataSignatureRef.current = '__unset__';
+      massStyleSignatureRef.current = '__unset__';
       amapRef.current = null;
       mapRef.current = null;
     };
@@ -280,13 +310,19 @@ export function FleetMap({ vehicles, selectedVin, onSelect, monitorMap, onSelect
     const AMap = amapRef.current;
     if (!mass || !AMap) return;
     clustersRef.current = new Map((monitorMap?.clusters ?? []).map((cluster) => [cluster.id, cluster]));
-    const baseStyles = COLORS.map((color) => ({ url: dotDataUrl(color), anchor: new AMap.Pixel(9, 9), size: new AMap.Size(18, 18) }));
     const clusterCounts = [...new Set((monitorMap?.clusters ?? []).map((cluster) => cluster.count))].sort((a, b) => a - b);
-    const clusterStyles = clusterCounts.map((count) => {
+    const styleSignature = clusterCounts.join(',');
-      const visual = clusterVisual(count);
+    if (massStyleSignatureRef.current !== styleSignature) {
-      return { url: visual.url, anchor: new AMap.Pixel(visual.diameter / 2, visual.diameter / 2), size: new AMap.Size(visual.diameter, visual.diameter) };
+      const baseStyles = COLORS.map((color) => ({ url: dotDataUrl(color), anchor: new AMap.Pixel(9, 9), size: new AMap.Size(18, 18) }));
-    });
+      const clusterStyles = clusterCounts.map((count) => {
-    mass.setStyle?.([...baseStyles, ...clusterStyles]);
+        const visual = clusterVisual(count);
+        return { url: visual.url, anchor: new AMap.Pixel(visual.diameter / 2, visual.diameter / 2), size: new AMap.Size(visual.diameter, visual.diameter) };
+      });
+      mass.setStyle?.([...baseStyles, ...clusterStyles]);
+      massStyleSignatureRef.current = styleSignature;
+    }
+    const dataSignature = massPointSignature(monitorMap, points);
+    if (massDataSignatureRef.current === dataSignature) return;
     const clusterStyleIndexes = new Map(clusterCounts.map((count, index) => [count, COLORS.length + index]));
     const data: AMapMassPoint[] = monitorMap ? [
       ...monitorMap.clusters.map((cluster) => ({ lnglat: wgs84ToGcj02(cluster.longitude, cluster.latitude), style: clusterStyleIndexes.get(cluster.count) ?? COLORS.length, id: cluster.id, label: `${cluster.count} 辆` })),
@@ -295,6 +331,7 @@ export function FleetMap({ vehicles, selectedVin, onSelect, monitorMap, onSelect
       lnglat: wgs84ToGcj02(vehicle.longitude, vehicle.latitude), style: styleIndex(vehicle), id: vehicle.vin, label: vehicle.plate || vehicle.vin
     }));
     mass.setData(data);
+    massDataSignatureRef.current = dataSignature;
   }, [monitorMap, points, state]);
 
   useEffect(() => {
@@ -303,13 +340,6 @@ export function FleetMap({ vehicles, selectedVin, onSelect, monitorMap, onSelect
     const AMap = amapRef.current;
     const map = mapRef.current;
     if (!labels || !denseLabels || !AMap?.LabelMarker || !map) return;
-    labels.clear();
-    denseLabels.clear();
-    if (!showLabels && !selectedVin) {
-      labels.setMap(null);
-      denseLabels.setMap(null);
-      return;
-    }
     const mapLabelPoints = (monitorMap
       ? monitorMap.points
       : points.map((vehicle) => ({ ...vehicle, status: vehicleStatus(vehicle) })));
@@ -318,13 +348,31 @@ export function FleetMap({ vehicles, selectedVin, onSelect, monitorMap, onSelect
       : mapLabelPoints;
     const labelPoints = showLabels ? allLabelPoints : allLabelPoints.filter((point) => point.vin === selectedVin);
     const showEveryPlate = mapZoom >= 19;
+    const layerMode = showEveryPlate ? 'dense' : 'normal';
     const activeLabels = showEveryPlate ? denseLabels : labels;
-    labels.setMap(showEveryPlate ? null : map);
+    if (labelLayerModeRef.current && labelLayerModeRef.current !== layerMode) {
-    denseLabels.setMap(showEveryPlate ? map : null);
+      (labelLayerModeRef.current === 'dense' ? denseLabels : labels).clear();
+      labelMarkersRef.current.clear();
+    }
+    labelLayerModeRef.current = layerMode;
+    const layerState = `${layerMode}:${labelPoints.length > 0 ? 'visible' : 'hidden'}`;
+    if (labelLayerStateRef.current !== layerState) {
+      labels.setMap(layerMode === 'normal' && labelPoints.length ? map : null);
+      denseLabels.setMap(layerMode === 'dense' && labelPoints.length ? map : null);
+      labelLayerStateRef.current = layerState;
+    }
     const densePlacements = showEveryPlate ? densePlatePlacements(labelPoints) : null;
-    const markers = labelPoints.map((point) => {
+    const nextMarkers = new Map<string, LabelMarkerEntry>();
+    const markersToAdd: AMapOverlay[] = [];
+    for (const point of labelPoints) {
       const placement = densePlacements?.get(point.vin);
-      return new AMap.LabelMarker!({
+      const signature = labelMarkerSignature(point, point.vin === selectedVin, placement);
+      const existing = labelMarkersRef.current.get(point.vin);
+      if (existing?.signature === signature) {
+        nextMarkers.set(point.vin, existing);
+        continue;
+      }
+      const marker = new AMap.LabelMarker!({
         name: point.plate || point.vin,
         position: wgs84ToGcj02(point.longitude, point.latitude),
         rank: point.vin === selectedVin ? 100 : 1,
@@ -350,8 +398,15 @@ export function FleetMap({ vehicles, selectedVin, onSelect, monitorMap, onSelect
           }
         }
       });
-    });
+      nextMarkers.set(point.vin, { marker, signature });
-    if (markers.length) activeLabels.add(markers);
+      markersToAdd.push(marker);
+    }
+    const markersToRemove = [...labelMarkersRef.current.entries()]
+      .filter(([vin, entry]) => nextMarkers.get(vin) !== entry)
+      .map(([, entry]) => entry.marker);
+    if (markersToRemove.length) activeLabels.remove(markersToRemove);
+    if (markersToAdd.length) activeLabels.add(markersToAdd);
+    labelMarkersRef.current = nextMarkers;
   }, [mapZoom, monitorMap, points, selectedTarget, selectedVin, showLabels, state]);
 
   useEffect(() => {
@@ -381,9 +436,10 @@ export function FleetMap({ vehicles, selectedVin, onSelect, monitorMap, onSelect
     } else if (selectionPositionRef.current && selectionPositionRef.current !== positionKey && followSelectedRef.current) {
       mapRef.current.panTo?.(mapPosition, 650);
     }
+    const previousPositionKey = selectionPositionRef.current;
     selectionPositionRef.current = positionKey;
     if (selectionKeyRef.current === selectionKey && selectionRef.current) {
-      selectionRef.current.setPosition?.(mapPosition);
+      if (previousPositionKey !== positionKey) selectionRef.current.setPosition?.(mapPosition);
       return;
     }
     selectionRef.current?.setMap?.(null);

vehicle-data-platform/docs/frontend-production-readiness.md

@@ -2,6 +2,12 @@
 
 This document records verified risks, the production controls that address them, and the next evidence to collect. It is intentionally operational: a passing build alone is not proof that the browser application is production-ready.
 
+## 2026-07-16: incremental fleet-map refresh
+
+The 15-second monitor refresh previously treated every new response object as a complete visual change. Even when only `asOf` changed, it regenerated MassMarks styles/data, cleared both label layers and constructed every plate marker again. With hundreds of visible vehicles this caused avoidable canvas work and periodic main-thread pressure.
+
+FleetMap now fingerprints only fields that affect map rendering. An unchanged refresh performs no AMap data/style/label mutation. A moving vehicle still updates MassMarks once, but the LabelsLayer removes and replaces only that vehicle's changed marker; full label-layer replacement is reserved for crossing the normal/dense zoom boundary. The selected ripple marker also skips redundant position writes. This uses the official AMap JS API 2.0 [`LabelsLayer.remove`](https://lbs.amap.com/api/javascript-api-v2/guide/amap-massmarker/label-marker) and `LabelMarker` update model instead of reconstructing all overlays. Unit tests assert zero map mutations for an `asOf`-only refresh and exactly one label replacement for one moved vehicle.
+
 ## 2026-07-16: high-cardinality address cache lifecycle
 
 The monitor list previously retained every manually resolved coordinate for 24 hours, and track replay inherited the global five-minute cache for every paused point. Long-running dispatch sessions could therefore accumulate address payloads across pages and arbitrary playback coordinates even after their components disappeared.