修复三维楼层自动切换与模型加载

- 优化建筑外观与馆内楼层的缩放自动切换状态
- 首次进入馆内默认加载 1F 楼层模型，后续重进保持上次楼层
- 手动楼层切换强制加载对应楼层模型，避免误用外观兜底
- 调整三维渲染色调、背景和灯光，减轻楼层模型灰蒙感

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/components/map/ThreeMap.vue

@@ -83,6 +83,7 @@ interface CameraFitOptions {
 interface LoadFloorOptions {
   preserveCurrentSceneUntilReady?: boolean
   suppressProgress?: boolean
+  allowOverviewFallback?: boolean
 }
 
 interface LoadModelOptions {
@@ -190,6 +191,7 @@ const props = withDefaults(defineProps<{
   routePreview?: GuideRouteResult | null
   showRoute?: boolean
   autoSwitch?: boolean
+  disableAutoExit?: boolean
   autoSwitchThresholdLow?: number
   autoSwitchThresholdHigh?: number
   autoSwitchCooldown?: number
@@ -205,6 +207,7 @@ const props = withDefaults(defineProps<{
   routePreview: null,
   showRoute: false,
   autoSwitch: true,
+  disableAutoExit: false,
   autoSwitchThresholdLow: 1.45,
   autoSwitchThresholdHigh: 3.8,
   autoSwitchCooldown: 2000
@@ -223,7 +226,7 @@ const containerRef = ref<ContainerRef>(null)
 const isLoading = ref(true)
 const loadError = ref(false)
 const loadingProgress = ref(0)
-const loadingMessage = ref('正在读取室内导览资源...')
+const loadingMessage = ref('正在读取馆内导览资源...')
 const activeView = ref<ViewMode>(props.initialView)
 const currentFloor = ref(props.initialFloorId)
 const selectedPOI = ref<RenderPoi | null>(null)
@@ -264,22 +267,28 @@ let isDisposed = false
 let pendingTargetFocus: TargetPoiFocusRequest | null = null
 let targetFocusQueue: Promise<unknown> = Promise.resolve()
 let modelLoadVersion = 0
+let hasLoadedFloorViewOnce = false
 let pointerDownState: { x: number; y: number } | null = null
 let cachedOverviewModel: THREE.Object3D | null = null
 let cachedSharedModelUrl = ''
 let autoSwitchOverviewMaxDim = 0
 
-// 自动切换状态
+// 自动切换状态：建筑外观积极进入，馆内锁定后再二段退出。
 let isAutoSwitchLocked = false
 let lastAutoSwitchTime = 0
 let lastControlDistance = 0
-let floorAutoSwitchProtectedUntil = 0
+let activeControlGestureStartedAt = 0
-let floorExitThresholdExceededSince = 0
+let indoorEntryGestureLocked = false
-let floorExitZoomOutAccumulatedDistance = 0
+let indoorContextLockedUntil = 0
+let floorExitCandidateStartedAt = 0
+let floorExitCandidateBaseDistance = 0
+let floorExitZoomOutAccumulatedRatio = 0
 let autoSwitchTemporarilyDisabled = false
 let autoSwitchDisableTimer: ReturnType<typeof setTimeout> | null = null
-let suppressNextAutoSwitchCheck = false
+let overviewEntryIntentStartedAt = 0
-let overviewWheelZoomStartDistance = 0
+let overviewEntryStartDistance = 0
+let overviewEntryZoomInRounds = 0
+let overviewWheelZoomInRounds = 0
 let overviewWheelZoomIntentUntil = 0
 let overviewWheelAutoSwitchTimer: ReturnType<typeof setTimeout> | null = null
 let isProgrammaticCameraChange = false
@@ -293,10 +302,19 @@ const poiHitTargetScaleMultiplier = 4.8
 const poiHitTargetCoreScaleMultiplier = 5.4
 const poiScreenHitRadiusPx = 64
 const poiScreenHitRadiusCorePx = 76
-const floorAutoSwitchProtectionMs = 1600
+const indoorContextLockMs = 5000
-const floorExitZoomOutIntentMinDeltaRatio = 0.01
+const indoorGestureExitGraceMs = 900
-const floorExitZoomOutAccumulatedRatio = 0.12
+const overviewEntryIntentWindowMs = 1200
-const floorExitThresholdHoldMs = 650
+const overviewEntryMinZoomInRatio = 0.04
+const overviewEntryAccumulatedRatio = 0.2
+const overviewEntryMinRounds = 2
+const overviewEntryMaxRounds = 4
+const overviewWheelEntryDelayMs = 180
+const floorExitCandidateThresholdMultiplier = 1.12
+const floorExitConfirmThresholdMultiplier = 1.34
+const floorExitZoomOutIntentMinDeltaRatio = 0.015
+const floorExitAccumulatedZoomOutRatio = 0.26
+const floorExitCandidateHoldMs = 900
 
 const syncControlInteractionOptions = () => {
   if (!controls) return
@@ -359,7 +377,7 @@ const floorExteriorNameKeywords = [
   '玻璃幕墙',
   '楼顶',
   '屋顶',
-  '室外'
+  '馆外'
 ]
 
 const overviewBuildingSubjectNameKeywords = [
@@ -727,11 +745,6 @@ const refreshPoiVisibilityByDistance = () => {
 
 const handleControlChange = () => {
   updatePoiVisibilityByDistance()
-  if (suppressNextAutoSwitchCheck) {
-    suppressNextAutoSwitchCheck = false
-    updateLastControlDistance()
-    return
-  }
   checkAutoSwitch()
 }
 
@@ -862,9 +875,19 @@ const updatePoiTapFeedback = (now: number) => {
 }
 
 const handleControlStart = () => {
+  activeControlGestureStartedAt = Date.now()
   cancelCameraTween({ manual: true })
 }
 
+const handleControlEnd = () => {
+  if (indoorEntryGestureLocked) {
+    indoorContextLockedUntil = Math.max(indoorContextLockedUntil, Date.now() + indoorGestureExitGraceMs)
+    indoorEntryGestureLocked = false
+  }
+  activeControlGestureStartedAt = 0
+  updateLastControlDistance()
+}
+
 const setProgress = (progress: number, message: string) => {
   loadingProgress.value = Math.min(100, Math.max(0, progress))
   loadingMessage.value = message
@@ -923,7 +946,7 @@ const initThree = async () => {
   }
 
   scene = new THREE.Scene()
-  scene.background = new THREE.Color(0xf1f3ee)
+  scene.background = new THREE.Color(0xf7f8f4)
 
   const width = Math.max(1, container.clientWidth)
   const height = Math.max(1, container.clientHeight)
@@ -938,8 +961,8 @@ const initThree = async () => {
   renderer.setSize(width, height)
   renderer.setPixelRatio(Math.min(window.devicePixelRatio || 1, 2))
   renderer.outputColorSpace = THREE.SRGBColorSpace
-  renderer.toneMapping = THREE.ACESFilmicToneMapping
+  renderer.toneMapping = THREE.NeutralToneMapping
-  renderer.toneMappingExposure = 1.05
+  renderer.toneMappingExposure = 1.0
   container.appendChild(renderer.domElement)
 
   controls = new OrbitControls(camera, renderer.domElement)
@@ -964,14 +987,14 @@ const initThree = async () => {
   routeGroup.name = 'GuideModelRoute'
   scene.add(routeGroup)
 
-  const ambientLight = new THREE.AmbientLight(0xffffff, 1.6)
+  const ambientLight = new THREE.AmbientLight(0xffffff, 0.9)
   scene.add(ambientLight)
 
-  const keyLight = new THREE.DirectionalLight(0xffffff, 2.2)
+  const keyLight = new THREE.DirectionalLight(0xffffff, 2.0)
   keyLight.position.set(80, 120, 60)
   scene.add(keyLight)
 
-  const fillLight = new THREE.DirectionalLight(0xdfeaff, 0.9)
+  const fillLight = new THREE.DirectionalLight(0xdfeaff, 0.45)
   fillLight.position.set(-80, 60, -80)
   scene.add(fillLight)
 
@@ -979,11 +1002,12 @@ const initThree = async () => {
   resizeObserver.observe(container)
   container.addEventListener('pointerdown', handlePointerDown)
   container.addEventListener('pointerup', handlePointerUp)
-  container.addEventListener('wheel', handleWheelIntent, { passive: true })
+  renderer.domElement.addEventListener('wheel', handleWheelIntent, { passive: true, capture: true })
 
   // 监听控制器变化，用于自动切换和点位可见层级更新
   if (controls) {
     controls.addEventListener('start', handleControlStart)
+    controls.addEventListener('end', handleControlEnd)
     controls.addEventListener('change', handleControlChange)
   }
 
@@ -1743,11 +1767,27 @@ const canAttachCachedSharedModel = (modelUrl: string) => (
   Boolean(cachedOverviewModel && cachedSharedModelUrl === modelUrl && scene)
 )
 
+const canAttachCachedOverviewModel = () => Boolean(cachedOverviewModel && scene)
+
 const canLoadFloorSilently = (floorId: string) => {
   const floor = floorIndex.value.find((item) => item.floorId === floorId)
   return Boolean(floor && canAttachCachedSharedModel(floor.modelUrl))
 }
 
+const getDefaultFloorId = () => (
+  floorIndex.value.find((floor) => floor.floorId === props.initialFloorId)?.floorId
+  || floorIndex.value.find((floor) => floor.floorId === 'L1')?.floorId
+  || floorIndex.value[0]?.floorId
+  || props.initialFloorId
+  || 'L1'
+)
+
+const getAutoEntryTargetFloorId = () => (
+  hasLoadedFloorViewOnce
+    ? currentFloor.value || getDefaultFloorId()
+    : getDefaultFloorId()
+)
+
 const hasRenderableSceneForFloorTransition = () => Boolean(scene && activeModel)
 
 const createMultiFloorItemFromSharedModel = (sourceModel: THREE.Object3D, floor: FloorIndexItem) => {
@@ -1784,19 +1824,34 @@ const updateLastControlDistance = () => {
   }
 }
 
+const resetOverviewEntryIntent = () => {
+  overviewEntryIntentStartedAt = 0
+  overviewEntryStartDistance = 0
+  overviewEntryZoomInRounds = 0
+  overviewWheelZoomInRounds = 0
+  overviewWheelZoomIntentUntil = 0
+}
+
+const resetFloorExitCandidate = () => {
+  floorExitCandidateStartedAt = 0
+  floorExitCandidateBaseDistance = 0
+  floorExitZoomOutAccumulatedRatio = 0
+}
+
 const markFloorAutoSwitchEntry = () => {
-  floorAutoSwitchProtectedUntil = Date.now() + floorAutoSwitchProtectionMs
+  indoorContextLockedUntil = Date.now() + indoorContextLockMs
-  floorExitThresholdExceededSince = 0
+  indoorEntryGestureLocked = activeControlGestureStartedAt > 0
-  floorExitZoomOutAccumulatedDistance = 0
+  resetOverviewEntryIntent()
+  resetFloorExitCandidate()
   updateLastControlDistance()
 }
 
 const resetAutoSwitchDistanceTracking = () => {
-  floorAutoSwitchProtectedUntil = 0
+  activeControlGestureStartedAt = 0
-  floorExitThresholdExceededSince = 0
+  indoorEntryGestureLocked = false
-  floorExitZoomOutAccumulatedDistance = 0
+  indoorContextLockedUntil = 0
-  overviewWheelZoomStartDistance = 0
+  resetOverviewEntryIntent()
-  overviewWheelZoomIntentUntil = 0
+  resetFloorExitCandidate()
   updateLastControlDistance()
 }
 
@@ -1807,6 +1862,25 @@ const clearOverviewWheelAutoSwitchTimer = () => {
   }
 }
 
+const hasOverviewWheelEntryRounds = () => (
+  activeView.value === 'overview'
+  && overviewWheelZoomInRounds >= overviewEntryMinRounds
+)
+
+const hasPendingOverviewWheelEntryIntent = (now: number) => (
+  hasOverviewWheelEntryRounds()
+  && isOverviewEntryIntentActive(now)
+)
+
+const canRunPendingOverviewEntry = (now: number) => (
+  props.autoSwitch
+  && !autoSwitchTemporarilyDisabled
+  && !isLoading.value
+  && !isAutoSwitchLocked
+  && now - lastAutoSwitchTime >= props.autoSwitchCooldown
+  && Boolean(controls && activeModel)
+)
+
 const handleWheelIntent = (event: WheelEvent) => {
   if (!controls || activeView.value !== 'overview' || event.deltaY >= 0) return
 
@@ -1814,47 +1888,125 @@ const handleWheelIntent = (event: WheelEvent) => {
   if (!Number.isFinite(distance)) return
 
   const now = Date.now()
-  if (!overviewWheelZoomStartDistance || now > overviewWheelZoomIntentUntil) {
+  if (!isOverviewEntryIntentActive(now)) {
-    overviewWheelZoomStartDistance = distance
+    overviewEntryIntentStartedAt = now
+    overviewEntryStartDistance = distance
+    overviewEntryZoomInRounds = 0
+    overviewWheelZoomInRounds = 0
   }
+  overviewEntryIntentStartedAt = now
+  overviewEntryZoomInRounds += 1
+  overviewWheelZoomInRounds += 1
   overviewWheelZoomIntentUntil = now + 900
 
   clearOverviewWheelAutoSwitchTimer()
   overviewWheelAutoSwitchTimer = setTimeout(() => {
+    const triggerNow = Date.now()
     overviewWheelAutoSwitchTimer = null
+    if (hasPendingOverviewWheelEntryIntent(triggerNow) && canRunPendingOverviewEntry(triggerNow)) {
       checkAutoSwitch({ forceOverviewEntry: true })
-  }, 180)
+    }
+  }, overviewWheelEntryDelayMs)
 }
 
-const shouldForceOverviewEntryFromWheel = (distance: number, now: number) => (
+const isOverviewEntryIntentActive = (now: number) => (
-  now <= overviewWheelZoomIntentUntil
+  overviewEntryIntentStartedAt > 0
-  && overviewWheelZoomStartDistance > 0
+  && (
-  && distance <= overviewWheelZoomStartDistance * 0.86
+    now - overviewEntryIntentStartedAt <= overviewEntryIntentWindowMs
+    || now <= overviewWheelZoomIntentUntil
+  )
 )
 
-const checkAutoSwitch = (options: { forceOverviewEntry?: boolean } = {}) => {
+const getOverviewEntryAccumulatedRatio = (distance: number) => {
-  // 检查是否启用自动切换
+  if (!overviewEntryStartDistance || !Number.isFinite(distance)) return 0
-  if (!props.autoSwitch || autoSwitchTemporarilyDisabled || isProgrammaticCameraChange || isLoading.value) {
+
+  return Math.max(0, 1 - distance / overviewEntryStartDistance)
+}
+
+const trackOverviewEntryIntent = (distance: number, previousDistance: number, now: number) => {
+  if (!Number.isFinite(distance) || !Number.isFinite(previousDistance) || previousDistance <= 0) return
+
+  const zoomInRatio = (previousDistance - distance) / previousDistance
+  const hasClearZoomIn = zoomInRatio >= overviewEntryMinZoomInRatio
+
+  if (!hasClearZoomIn) {
+    if (!isOverviewEntryIntentActive(now)) {
+      resetOverviewEntryIntent()
+    }
+    return
+  }
+
+  if (!isOverviewEntryIntentActive(now) || !overviewEntryStartDistance || distance > overviewEntryStartDistance) {
+    overviewEntryIntentStartedAt = now
+    overviewEntryStartDistance = previousDistance
+    overviewEntryZoomInRounds = 0
+  }
+
+  overviewEntryIntentStartedAt = now
+  overviewEntryZoomInRounds += 1
+
+  const accumulatedRatio = getOverviewEntryAccumulatedRatio(distance)
+  overviewEntryZoomInRounds = Math.max(
+    overviewEntryZoomInRounds,
+    Math.floor(accumulatedRatio / overviewEntryMinZoomInRatio)
+  )
+}
+
+const shouldEnterFloorFromOverview = (
+  distance: number,
+  maxDim: number,
+  now: number,
+  hasForcedOverviewEntryIntent = false
+) => {
+  const enterFloorAt = maxDim * props.autoSwitchThresholdLow
+  if (distance <= enterFloorAt) return true
+
+  if (hasForcedOverviewEntryIntent) return true
+  if (!isOverviewEntryIntentActive(now)) return false
+
+  const accumulatedRatio = getOverviewEntryAccumulatedRatio(distance)
+  const hasRepeatedZoomIn = overviewEntryZoomInRounds >= overviewEntryMinRounds
+    && accumulatedRatio >= overviewEntryAccumulatedRatio
+  const hasSustainedZoomIn = overviewEntryZoomInRounds >= overviewEntryMaxRounds
+    && accumulatedRatio >= overviewEntryAccumulatedRatio * 0.68
+
+  return hasRepeatedZoomIn || hasSustainedZoomIn
+}
+
+const isFloorAutoExitLocked = (now: number) => (
+  props.disableAutoExit
+  || Boolean(props.targetFocus)
+  || indoorEntryGestureLocked
+  || now < indoorContextLockedUntil
+)
+
+const checkAutoSwitch = (options: { forceOverviewEntry?: boolean } = {}) => {
+  const now = Date.now()
+  const hasForcedOverviewEntryIntent = options.forceOverviewEntry === true
+    && hasOverviewWheelEntryRounds()
+    && canRunPendingOverviewEntry(now)
+
+  if (
+    !props.autoSwitch
+    || autoSwitchTemporarilyDisabled
+    || isLoading.value
+    || (!hasForcedOverviewEntryIntent && isProgrammaticCameraChange)
+  ) {
     return
   }
 
-  // 检查加载锁
   if (isAutoSwitchLocked) {
     emit('autoSwitchBlocked', { reason: 'loading-locked' })
     return
   }
 
-  // 检查冷却时间
-  const now = Date.now()
   if (now - lastAutoSwitchTime < props.autoSwitchCooldown) {
     emit('autoSwitchBlocked', { reason: 'cooldown' })
     return
   }
 
-  // 检查必要条件
   if (!controls || !activeModel || activeView.value === 'multi') return
 
-  // 获取当前距离
   const distance = controls.getDistance()
   const previousDistance = lastControlDistance || distance
   const distanceDelta = distance - previousDistance
@@ -1863,20 +2015,21 @@ const checkAutoSwitch = (options: { forceOverviewEntry?: boolean } = {}) => {
   // 自动切换使用全馆稳定尺寸，避免单楼层可见性过滤压低 floor -> overview 阈值。
   const maxDim = autoSwitchOverviewMaxDim || getObjectMaxDim(activeModel)
 
-  const enterFloorAt = maxDim * props.autoSwitchThresholdLow
+  if (activeView.value === 'overview') {
-  const exitFloorAt = maxDim * props.autoSwitchThresholdHigh
+    if (!hasForcedOverviewEntryIntent) {
+      trackOverviewEntryIntent(distance, previousDistance, now)
+    }
 
-  // 判断是否需要切换
+    if (!shouldEnterFloorFromOverview(distance, maxDim, now, hasForcedOverviewEntryIntent)) {
-  if (activeView.value === 'overview' && (distance < enterFloorAt || (options.forceOverviewEntry && shouldForceOverviewEntryFromWheel(distance, now)))) {
+      return
-    // 从建筑外观自动切换到单楼层
+    }
-    const targetFloorId = currentFloor.value || props.initialFloorId || 'L1'
+
+    const targetFloorId = getAutoEntryTargetFloorId()
     const hasSceneToKeep = hasRenderableSceneForFloorTransition()
     isAutoSwitchLocked = true
     lastAutoSwitchTime = now
-    floorExitThresholdExceededSince = 0
+    resetFloorExitCandidate()
-    floorExitZoomOutAccumulatedDistance = 0
+    resetOverviewEntryIntent()
-    overviewWheelZoomStartDistance = 0
-    overviewWheelZoomIntentUntil = 0
     clearOverviewWheelAutoSwitchTimer()
 
     void runAutoSwitchLoad(
@@ -1888,7 +2041,8 @@ const checkAutoSwitch = (options: { forceOverviewEntry?: boolean } = {}) => {
       },
       () => loadFloor(targetFloorId, {
         preserveCurrentSceneUntilReady: hasSceneToKeep,
-        suppressProgress: hasSceneToKeep
+        suppressProgress: hasSceneToKeep,
+        allowOverviewFallback: true
       }),
       '单楼层模型加载失败',
       { showLoading: !hasSceneToKeep && !canLoadFloorSilently(targetFloorId) }
@@ -1896,49 +2050,53 @@ const checkAutoSwitch = (options: { forceOverviewEntry?: boolean } = {}) => {
     return
   }
 
-  if (activeView.value !== 'floor' || props.targetFocus) {
+  if (activeView.value !== 'floor') {
-    floorExitThresholdExceededSince = 0
+    resetFloorExitCandidate()
-    floorExitZoomOutAccumulatedDistance = 0
     return
   }
 
-  if (now < floorAutoSwitchProtectedUntil) {
+  if (isFloorAutoExitLocked(now)) {
-    floorExitThresholdExceededSince = 0
+    resetFloorExitCandidate()
-    floorExitZoomOutAccumulatedDistance = 0
     return
   }
 
-  const zoomOutIntentDelta = Math.max(maxDim * floorExitZoomOutIntentMinDeltaRatio, 1)
+  const baseExitThreshold = maxDim * props.autoSwitchThresholdHigh
-  const isClearZoomOutIntent = distanceDelta > zoomOutIntentDelta
+  const candidateExitAt = baseExitThreshold * floorExitCandidateThresholdMultiplier
-  const isBeyondExitThreshold = distance > exitFloorAt
+  const confirmExitAt = baseExitThreshold * floorExitConfirmThresholdMultiplier
+  const isBeyondCandidateThreshold = distance >= candidateExitAt
 
-  if (!isBeyondExitThreshold) {
+  if (!isBeyondCandidateThreshold) {
-    floorExitThresholdExceededSince = 0
+    resetFloorExitCandidate()
-    floorExitZoomOutAccumulatedDistance = 0
     return
   }
 
-  if (isClearZoomOutIntent) {
+  if (!floorExitCandidateStartedAt) {
-    floorExitZoomOutAccumulatedDistance += distanceDelta
+    floorExitCandidateStartedAt = now
-    if (!floorExitThresholdExceededSince) {
+    floorExitCandidateBaseDistance = Math.max(previousDistance, distance, 1)
-      floorExitThresholdExceededSince = now
+    floorExitZoomOutAccumulatedRatio = 0
-    }
+    return
-  }
+  }
-
+
-  const requiredZoomOutDistance = Math.max(maxDim * floorExitZoomOutAccumulatedRatio, 8)
+  const zoomOutRatio = previousDistance > 0 ? distanceDelta / previousDistance : 0
-  if (
+  const isClearZoomOutIntent = zoomOutRatio >= floorExitZoomOutIntentMinDeltaRatio
-    !floorExitThresholdExceededSince
+  if (isClearZoomOutIntent || distance > floorExitCandidateBaseDistance) {
-    || floorExitZoomOutAccumulatedDistance < requiredZoomOutDistance
+    floorExitZoomOutAccumulatedRatio = Math.max(
-  ) {
+      floorExitZoomOutAccumulatedRatio,
+      distance / Math.max(floorExitCandidateBaseDistance, 1) - 1
+    )
+  }
+
+  const hasConfirmedScale = distance >= confirmExitAt
+    && floorExitZoomOutAccumulatedRatio >= floorExitAccumulatedZoomOutRatio
+  const hasHeldCandidate = now - floorExitCandidateStartedAt >= floorExitCandidateHoldMs
+
+  if (!hasConfirmedScale || !hasHeldCandidate) {
     return
   }
 
-  if (now - floorExitThresholdExceededSince >= floorExitThresholdHoldMs) {
-    // 从单楼层自动切换到完整外围模型
   isAutoSwitchLocked = true
   lastAutoSwitchTime = now
-    floorExitThresholdExceededSince = 0
+  resetFloorExitCandidate()
-    floorExitZoomOutAccumulatedDistance = 0
 
   void runAutoSwitchLoad(
     {
@@ -1951,7 +2109,6 @@ const checkAutoSwitch = (options: { forceOverviewEntry?: boolean } = {}) => {
     '建筑外观模型加载失败'
   )
 }
-}
 
 const runAutoSwitchLoad = async (
   event: { from: 'overview' | 'floor'; to: 'overview' | 'floor'; trigger: 'zoom-in' | 'zoom-out'; distance: number },
@@ -1974,7 +2131,7 @@ const runAutoSwitchLoad = async (
   } catch (error) {
     if (isStaleModelLoadError(error)) return
 
-    console.error('室内 3D 自动视角切换失败:', error)
+    console.error('馆内 3D 自动视角切换失败:', error)
     loadError.value = true
     isLoading.value = false
     setProgress(0, error instanceof Error ? error.message : fallbackMessage)
@@ -1996,10 +2153,6 @@ const disableAutoSwitchTemporarily = (durationMs: number) => {
   }, durationMs)
 }
 
-const suppressAutoSwitchOnce = () => {
-  suppressNextAutoSwitchCheck = true
-}
-
 const setCameraView = (
   center: THREE.Vector3,
   maxDim: number,
@@ -2093,22 +2246,16 @@ const zoomCamera = (direction: 'in' | 'out', options: { source?: ZoomCameraSourc
 
   if (!Number.isFinite(nextDistance) || nextDistance <= 0) return
 
-  const shouldSuppressAutoSwitch = options.source === 'button'
+  const shouldTrackUserZoom = options.source === 'button'
-  if (shouldSuppressAutoSwitch) {
-    suppressAutoSwitchOnce()
-  }
 
   offset.setLength(nextDistance)
   const nextPosition = controls.target.clone().add(offset)
   moveCameraTo(nextPosition, controls.target, {
-    onComplete: shouldSuppressAutoSwitch
+    onComplete: handleControlChange
-      ? () => {
-        suppressAutoSwitchOnce()
-        handleControlChange()
-      }
-      : handleControlChange
   })
-  lastControlDistance = nextDistance
+  if (shouldTrackUserZoom) {
+    lastControlDistance = currentDistance
+  }
 
   handleControlChange()
 }
@@ -2166,9 +2313,10 @@ const attachCachedSharedModel = (
   modelUrl: string,
   name: string,
   loadToken: number,
-  floorId?: string
+  floorId?: string,
+  options: { allowAnyCachedOverview?: boolean } = {}
 ) => {
-  if (!cachedOverviewModel || cachedSharedModelUrl !== modelUrl || !scene) return false
+  if (!cachedOverviewModel || (!options.allowAnyCachedOverview && cachedSharedModelUrl !== modelUrl) || !scene) return false
 
   const targetScene = scene
   activeModel = cachedOverviewModel
@@ -2186,8 +2334,12 @@ const loadFloor = async (floorId: string, options: LoadFloorOptions = {}) => {
   if (!floor || !scene) return
 
   const loadToken = startModelLoad()
-  const canUseCachedModel = canAttachCachedSharedModel(floor.modelUrl)
+  const canUseExactCachedModel = canAttachCachedSharedModel(floor.modelUrl)
-  const preserveCurrentSceneUntilReady = options.preserveCurrentSceneUntilReady && !canUseCachedModel
+  const canUseOverviewFallback = !canUseExactCachedModel
+    && Boolean(options.allowOverviewFallback)
+    && Boolean(options.preserveCurrentSceneUntilReady)
+    && canAttachCachedOverviewModel()
+  const preserveCurrentSceneUntilReady = options.preserveCurrentSceneUntilReady && !canUseExactCachedModel
   let nextModel: THREE.Object3D | null = null
 
   if (!preserveCurrentSceneUntilReady) {
@@ -2196,15 +2348,23 @@ const loadFloor = async (floorId: string, options: LoadFloorOptions = {}) => {
     clearSceneData()
   }
 
-  if (canUseCachedModel) {
+  if (canUseExactCachedModel) {
     activeView.value = 'floor'
     currentFloor.value = floor.floorId
-    attachCachedSharedModel(floor.modelUrl, `GuideFloorModel_${floor.floorId}`, loadToken, floor.floorId)
+    attachCachedSharedModel(
+      floor.modelUrl,
+      `GuideFloorModel_${floor.floorId}`,
+      loadToken,
+      floor.floorId
+    )
   } else {
+    let gltf: GLTF | null = null
+
+    try {
       if (!options.suppressProgress) {
         setProgress(18, `正在加载 ${formatFloorLabel(floor.floorId)} 模型...`)
       }
-    const gltf = await loadModel(
+      gltf = await loadModel(
         floor.modelUrl,
         `正在加载 ${formatFloorLabel(floor.floorId)} 模型`,
         loadToken,
@@ -2216,7 +2376,24 @@ const loadFloor = async (floorId: string, options: LoadFloorOptions = {}) => {
         disposeObject(gltf.scene)
         throw error
       }
+    } catch (error) {
+      if (isStaleModelLoadError(error) || !canUseOverviewFallback) {
+        throw error
+      }
 
+      activeView.value = 'floor'
+      currentFloor.value = floor.floorId
+      clearSceneData()
+      attachCachedSharedModel(
+        floor.modelUrl,
+        `GuideFloorModel_${floor.floorId}`,
+        loadToken,
+        floor.floorId,
+        { allowAnyCachedOverview: true }
+      )
+    }
+
+    if (gltf) {
       const targetScene = scene
       if (!targetScene) {
         disposeObject(gltf.scene)
@@ -2251,8 +2428,10 @@ const loadFloor = async (floorId: string, options: LoadFloorOptions = {}) => {
       }
       targetScene.add(activeModel)
     }
+  }
 
   if (!activeModel) throw createStaleModelLoadError()
+  hasLoadedFloorViewOnce = true
   fitCameraToObject(activeModel)
   markFloorAutoSwitchEntry()
 
@@ -3142,7 +3321,7 @@ const queueTargetFocus = (request: TargetPoiFocusRequest | null) => {
 }
 
 const loadModelPackage = async () => {
-  setProgress(8, '正在读取室内导览资源...')
+  setProgress(8, '正在读取馆内导览资源...')
   const packageData = await props.modelSource.loadPackage()
   renderPackage.value = packageData
 
@@ -3176,18 +3355,19 @@ const init3DScene = async () => {
     isLoading.value = true
     loadError.value = false
     selectedPOI.value = null
+    hasLoadedFloorViewOnce = false
     setProgress(0, '正在初始化三维场景...')
 
     await initThree()
     await loadModelPackage()
 
-    setProgress(100, '室内三维模型加载完成')
+    setProgress(100, '馆内三维模型加载完成')
     isLoading.value = false
     queueTargetFocus(pendingTargetFocus || props.targetFocus || null)
   } catch (error) {
     if (isStaleModelLoadError(error)) return
 
-    console.error('室内 3D 模型资源加载失败:', error)
+    console.error('馆内 3D 模型资源加载失败:', error)
     loadError.value = true
     isLoading.value = false
     setProgress(0, error instanceof Error ? error.message : '请检查模型资源或网络状态后重试')
@@ -3269,7 +3449,7 @@ const disposeScene = () => {
   const container = getContainerElement()
   container?.removeEventListener('pointerdown', handlePointerDown)
   container?.removeEventListener('pointerup', handlePointerUp)
-  container?.removeEventListener('wheel', handleWheelIntent)
+  renderer?.domElement.removeEventListener('wheel', handleWheelIntent, true)
 
   resizeObserver?.disconnect()
   resizeObserver = null
@@ -3277,6 +3457,7 @@ const disposeScene = () => {
   // 清理自动切换相关资源
   if (controls) {
     controls.removeEventListener('start', handleControlStart)
+    controls.removeEventListener('end', handleControlEnd)
     controls.removeEventListener('change', handleControlChange)
     controls.dispose()
   }
@@ -3292,10 +3473,11 @@ const disposeScene = () => {
   cameraTween = null
   isProgrammaticCameraChange = false
   lastControlDistance = 0
-  suppressNextAutoSwitchCheck = false
+  activeControlGestureStartedAt = 0
-  floorAutoSwitchProtectedUntil = 0
+  indoorEntryGestureLocked = false
-  floorExitThresholdExceededSince = 0
+  indoorContextLockedUntil = 0
-  floorExitZoomOutAccumulatedDistance = 0
+  resetOverviewEntryIntent()
+  resetFloorExitCandidate()
 
   clearSceneData()
   disposePoiMarkerCache()
@@ -3393,7 +3575,7 @@ onUnmounted(() => {
   width: 100%;
   height: 100%;
   overflow: hidden;
-  background: #f1f3ee;
+  background: #f7f8f4;
 }
 
 .three-canvas-wrapper {
@@ -3416,7 +3598,7 @@ onUnmounted(() => {
   display: flex;
   align-items: center;
   justify-content: center;
-  background: rgba(241, 243, 238, 0.9);
+  background: rgba(247, 248, 244, 0.9);
   z-index: 20;
 }