path: root/src/LivingVillage.Desktop/Game.fs

namespace LivingVillage.Desktop

open System
open Microsoft.Xna.Framework
open Microsoft.Xna.Framework.Graphics
open Microsoft.Xna.Framework.Input
open LivingVillage.Kernel
open LivingVillage.Kernel.Sim
open LivingVillage.Desktop.ChineseText
open LivingVillage.Desktop.VillagePresentation

module PixelText =
    let private glyphs =
        [ 'A', [| "01110"; "10001"; "10001"; "11111"; "10001"; "10001"; "10001" |]
          'B', [| "11110"; "10001"; "10001"; "11110"; "10001"; "10001"; "11110" |]
          'C', [| "01111"; "10000"; "10000"; "10000"; "10000"; "10000"; "01111" |]
          'D', [| "11110"; "10001"; "10001"; "10001"; "10001"; "10001"; "11110" |]
          'E', [| "11111"; "10000"; "10000"; "11110"; "10000"; "10000"; "11111" |]
          'F', [| "11111"; "10000"; "10000"; "11110"; "10000"; "10000"; "10000" |]
          'G', [| "01111"; "10000"; "10000"; "10111"; "10001"; "10001"; "01111" |]
          'H', [| "10001"; "10001"; "10001"; "11111"; "10001"; "10001"; "10001" |]
          'I', [| "11111"; "00100"; "00100"; "00100"; "00100"; "00100"; "11111" |]
          'J', [| "00111"; "00010"; "00010"; "00010"; "00010"; "10010"; "01100" |]
          'K', [| "10001"; "10010"; "10100"; "11000"; "10100"; "10010"; "10001" |]
          'L', [| "10000"; "10000"; "10000"; "10000"; "10000"; "10000"; "11111" |]
          'M', [| "10001"; "11011"; "10101"; "10101"; "10001"; "10001"; "10001" |]
          'N', [| "10001"; "11001"; "10101"; "10011"; "10001"; "10001"; "10001" |]
          'O', [| "01110"; "10001"; "10001"; "10001"; "10001"; "10001"; "01110" |]
          'P', [| "11110"; "10001"; "10001"; "11110"; "10000"; "10000"; "10000" |]
          'Q', [| "01110"; "10001"; "10001"; "10001"; "10101"; "10010"; "01101" |]
          'R', [| "11110"; "10001"; "10001"; "11110"; "10100"; "10010"; "10001" |]
          'S', [| "01111"; "10000"; "10000"; "01110"; "00001"; "00001"; "11110" |]
          'T', [| "11111"; "00100"; "00100"; "00100"; "00100"; "00100"; "00100" |]
          'U', [| "10001"; "10001"; "10001"; "10001"; "10001"; "10001"; "01110" |]
          'V', [| "10001"; "10001"; "10001"; "10001"; "10001"; "01010"; "00100" |]
          'W', [| "10001"; "10001"; "10001"; "10101"; "10101"; "11011"; "10001" |]
          'X', [| "10001"; "10001"; "01010"; "00100"; "01010"; "10001"; "10001" |]
          'Y', [| "10001"; "10001"; "01010"; "00100"; "00100"; "00100"; "00100" |]
          'Z', [| "11111"; "00001"; "00010"; "00100"; "01000"; "10000"; "11111" |]
          '0', [| "01110"; "10001"; "10011"; "10101"; "11001"; "10001"; "01110" |]
          '1', [| "00100"; "01100"; "00100"; "00100"; "00100"; "00100"; "01110" |]
          '2', [| "01110"; "10001"; "00001"; "00010"; "00100"; "01000"; "11111" |]
          '3', [| "11110"; "00001"; "00001"; "01110"; "00001"; "00001"; "11110" |]
          '4', [| "00010"; "00110"; "01010"; "10010"; "11111"; "00010"; "00010" |]
          '5', [| "11111"; "10000"; "10000"; "11110"; "00001"; "00001"; "11110" |]
          '6', [| "01110"; "10000"; "10000"; "11110"; "10001"; "10001"; "01110" |]
          '7', [| "11111"; "00001"; "00010"; "00100"; "01000"; "01000"; "01000" |]
          '8', [| "01110"; "10001"; "10001"; "01110"; "10001"; "10001"; "01110" |]
          '9', [| "01110"; "10001"; "10001"; "01111"; "00001"; "00001"; "01110" |]
          ('-', [| "00000"; "00000"; "00000"; "11111"; "00000"; "00000"; "00000" |])
          ('.', [| "00000"; "00000"; "00000"; "00000"; "00000"; "00110"; "00110" |])
          ('=', [| "00000"; "11111"; "00000"; "00000"; "11111"; "00000"; "00000" |])
          (':', [| "00000"; "00110"; "00110"; "00000"; "00110"; "00110"; "00000" |])
          (';', [| "00000"; "00110"; "00110"; "00000"; "00110"; "00100"; "01000" |])
          ('/', [| "00001"; "00010"; "00010"; "00100"; "01000"; "01000"; "10000" |])
          ('>', [| "10000"; "01000"; "00100"; "00010"; "00100"; "01000"; "10000" |])
          ('?', [| "01110"; "10001"; "00001"; "00010"; "00100"; "00000"; "00100" |]) ]
         |> Map.ofList

    let isRenderable (text: string) : bool =
        not (isNull text)
        && text
           |> Seq.forall (fun character ->
               character = ' '
               || Map.containsKey (Char.ToUpperInvariant character) glyphs
                || CjkGlyphAtlas.contains character)

    let draw (spriteBatch: SpriteBatch) (pixel: Texture2D) (cjkAtlas: Texture2D) (x: int) (y: int) (scale: int) (color: Color) (text: string) =
        let mutable cursor = x
        for character in text.ToUpperInvariant() do
            if character = ' ' then
                cursor <- cursor + (4 * scale)
            elif CjkGlyphAtlas.sourceRectangle character |> Option.isSome then
                let source = CjkGlyphAtlas.sourceRectangle character |> Option.get
                let glyphPixels = 8 * scale
                spriteBatch.Draw(
                    cjkAtlas,
                    Rectangle(cursor, y, glyphPixels, glyphPixels),
                    Nullable<Rectangle>(source),
                    color)
                cursor <- cursor + glyphPixels
            else
                match glyphs |> Map.tryFind character with
                | Some rows ->
                    for row in 0 .. rows.Length - 1 do
                        for column in 0 .. rows.[row].Length - 1 do
                            if rows.[row].[column] = '1' then
                                spriteBatch.Draw(pixel, Rectangle(cursor + column * scale, y + row * scale, scale, scale), color)
                    cursor <- cursor + (6 * scale)
                | None ->
                    // Unsupported characters are intentionally blank, never a fake glyph.
                    cursor <- cursor + (6 * scale)

type LivingVillageGame() as this =
    inherit Game()

    let autoplay = (Environment.GetEnvironmentVariable("LV_AUTOPLAY") = "1") || (Environment.GetEnvironmentVariable("LV_MAP_TOUR") = "1")
    let autoplayFlow = Environment.GetEnvironmentVariable("LV_AUTOPLAY_FLOW") = "1"
    let sampleMode = Environment.GetEnvironmentVariable("LV_AUTOPLAY_SAMPLE") = "1"
    let menuShotMode = Environment.GetEnvironmentVariable("LV_AUTOPLAY_MENU_SHOT") = "1"
    let daylightAutoplay = Environment.GetEnvironmentVariable("LV_AUTOPLAY_DAYLIGHT") = "1"
    let automated = autoplay || autoplayFlow
    let modeName =
        if sampleMode then "sample"
        elif autoplayFlow then "autoplay-flow"
        elif autoplay then "autoplay"
        else "keyboard"
    let configuredStepsPerFrame =
        match Environment.GetEnvironmentVariable("LV_STEPS_PER_FRAME") with
        | null | "" -> 1
        | s ->
            match Int32.TryParse s with
            | true, n when n > 0 -> n
            | _ -> 1
    let initialSimulationControl, initialLegacyStepsPerFrame =
        SimulationControl.initialForConfiguredSteps configuredStepsPerFrame
    let startSimulationControl =
        if sampleMode then SimulationControl.setSpeed TwoX initialSimulationControl else initialSimulationControl
    let savePath =
        match Environment.GetEnvironmentVariable("LV_SAVE_PATH") with
        | null | "" -> "living-village.save"
        | path -> path
    let graphics = new GraphicsDeviceManager(this)
    let mutable spriteBatch = Unchecked.defaultof<SpriteBatch>
    let mutable artTextures = Unchecked.defaultof<VillageArt.ArtTextures>
    let mutable cjkAtlas = Unchecked.defaultof<Texture2D>
    let mutable pixel = Unchecked.defaultof<Texture2D>
    let renderPlan = VillageArt.sampleRenderPlan ()
    let legacyMapMode = Environment.GetEnvironmentVariable("LV_LEGACY_MAP") = "1"
    let mapScale =
        match Environment.GetEnvironmentVariable("LV_MAP_SCALE") with
        | null | "" -> 1
        | v -> match Int32.TryParse v with (true, value) -> max 1 value | _ -> 1
    let mapTourMode = Environment.GetEnvironmentVariable("LV_MAP_TOUR") = "1"
    // P20 第三步：默认可玩世界走 256x192 生成器（核心可达区站位）；LV_LEGACY_MAP=1 回退 64x48。
    let riverscapeActive = not legacyMapMode && not mapTourMode && mapScale <= 1
    let riverscapeMap : MapGen.Result option =
        if riverscapeActive then
            Sim.configureBounds 256 192
            Some (MapGen.generateWithSize 256 192 42UL)
        else
            None
    let riverscapeTourMode = Environment.GetEnvironmentVariable("LV_RIVERSCAPE_TOUR") = "1" && riverscapeActive
    /// 巡游路点：第一座桥的整列（含两端外沿）+ 民居门 + 核心中心，用于桥面行走取证。
    let riverscapeTourWaypoints () : (int * int) list =
        match riverscapeMap with
        | None -> []
        | Some map ->
            let bridgeStops =
                map.Bridges
                |> List.groupBy fst
                |> List.sortBy fst
                |> List.truncate 1
                |> List.collect (fun (x, entries) ->
                    let ys = entries |> List.map snd |> List.sort
                    [ (x, List.min ys - 2) ] @ [ for y in ys -> (x, y) ] @ [ (x, List.max ys + 2) ])
            let doors = map.Buildings |> List.map (fun building -> (building.DoorX, building.DoorY))
            let core = ((map.Core.MinX + map.Core.MaxX) / 2, (map.Core.MinY + map.Core.MaxY) / 2)
            (bridgeStops @ doors @ [ core ])
            |> List.filter (fun (x, y) -> x >= 0 && x < map.Width && y >= 0 && y < map.Height)
            |> List.distinct
    // Evidence hook: pin the starting wall-clock hour (e.g. 20.75 for 黄昏), desktop-only.
    let startHourOverride =
        match Environment.GetEnvironmentVariable("LV_AUTOPLAY_START_HOUR") with
        | null | "" -> None
        | value ->
            match Double.TryParse(value, Globalization.NumberStyles.Float, Globalization.CultureInfo.InvariantCulture) with
            | true, hour -> Some hour
            | _ -> None
    // Single source of truth for the starting tick so the sample/autoplay path (which
    // re-creates the world via StartNewGame) honours the evidence hour too.
    let evidenceStartTick () =
        M6Presentation.resolveStartTick startHourOverride daylightAutoplay
    let withStartTick (world: World) : World =
        let tick = evidenceStartTick ()
        { world with Tick = tick; Time = float tick * Sim.dtSeconds }
    let initialWorldForMode (occupation: Occupation.State option) : World =
        match riverscapeMap with
        | Some map ->
            let core = map.Core
            WorldBootstrap.initialWorldWithPlacement
                daylightAutoplay
                42UL
                Sim.npcCount
                ((core.MinX + core.MaxX) / 2, (core.MinY + core.MaxY) / 2)
                map.Spawns
                occupation
        | None -> WorldBootstrap.initialWorldWithOccupation daylightAutoplay 42UL Sim.npcCount occupation
    let createInitialWorld () =
        initialWorldForMode None |> withStartTick
    let mutable world = createInitialWorld ()
    let mutable camera = Vector2.Zero
    let mutable avatarFacing = VillageArt.SouthFacing
    let mutable avatarMoving = false
    let mutable fpsFrames = 0
    let mutable fpsSeconds = 0.0
    let mutable prevKb = Unchecked.defaultof<KeyboardState>
    let mutable relationView = false
    let mutable relationSnapshot: float32[,] option = None
    let mutable m5View = M5Interaction.initial
    let mutable simulationControl = startSimulationControl
    let mutable legacyStepsPerFrame = (if sampleMode then None else initialLegacyStepsPerFrame)
    let mutable menu = MenuState.create startSimulationControl false
    let mutable splashActive = true
    let mutable splashFrame = 0L
    let mutable menuEntranceFrame = 0L
    let mutable menuShotFrame = 0L
    let mutable autoplayFrames = 0
    let mutable flowStep = 0
    let mutable flowHold = 0
    let mutable sampleState = SampleScript.initial
    let mutable hudClock = 0L
    let mutable hudStatus = ""
    let mutable hudStatusAt = 0L
    let mutable pauseHelpControl: SimulationControl option = None
    let recordMode = Environment.GetEnvironmentVariable("LV_AUTOPLAY_RECORD") = "1"
    let recordDirectory =
        match Environment.GetEnvironmentVariable("LV_RECORD_DIR") with
        | null | "" -> "/tmp/lv-p5-prompt"
        | v -> v
    let recordEvery = int (
        match Environment.GetEnvironmentVariable("LV_RECORD_EVERY") with
        | null | "" -> 25
        | v -> match Int32.TryParse v with (true, value) -> max 1 value | _ -> 25)
    let mutable recordIndex = 0
    let recordName =
        match Environment.GetEnvironmentVariable("LV_RECORD_NAME") with
        | null | "" -> "rec-frame-"
        | v -> v
    let mutable tourWaypoints =
        [ (1, 1); (255, 191); (509, 381); (256, 60); (256, 300); (80, 200); (430, 300) ]
    let mutable tourIndex = 0
    let mutable tourFrame = 0
    // P20 证据钩子：LV_MAPGEN_SHOT=1 时用参数化生成器出整图 + 视口裁剪帧，拍完即退出。
    let mapGenShotMode = Environment.GetEnvironmentVariable("LV_MAPGEN_SHOT") = "1"
    let mapGenWidth =
        match Environment.GetEnvironmentVariable("LV_MAPGEN_WIDTH") with
        | null | "" -> 256
        | v -> match Int32.TryParse v with (true, value) when value > 0 -> value | _ -> 256
    let mapGenHeight =
        match Environment.GetEnvironmentVariable("LV_MAPGEN_HEIGHT") with
        | null | "" -> 192
        | v -> match Int32.TryParse v with (true, value) when value > 0 -> value | _ -> 192
    let mapGenSeed =
        match Environment.GetEnvironmentVariable("LV_MAPGEN_SEED") with
        | null | "" -> 4242UL
        | v -> match UInt64.TryParse v with (true, value) -> value | _ -> 4242UL
    let mutable mapGenResult = Unchecked.defaultof<MapGen.Result>
    let mutable mapGenGenMs = 0.0

    do
        if mapScale > 1 then
            Sim.configureBounds (64 * mapScale) (48 * mapScale)
            ProceduralMap.activate (uint64 4242)
        if mapGenShotMode then
            let stopwatch = System.Diagnostics.Stopwatch.StartNew()
            mapGenResult <- MapGen.generateWithSize mapGenWidth mapGenHeight mapGenSeed
            stopwatch.Stop()
            mapGenGenMs <- stopwatch.Elapsed.TotalMilliseconds
            printfn
                "mapgen-gen size=%dx%d seed=%d gen_ms=%.2f tiles=%d reachable_ok=%b reachable_tiles=%d spawns=%d"
                mapGenResult.Width
                mapGenResult.Height
                (int mapGenResult.Seed)
                mapGenGenMs
                mapGenResult.Tiles.Length
                mapGenResult.ReachabilityOk
                mapGenResult.ReachableTiles
                mapGenResult.Spawns.Length
        if mapTourMode then
            tourWaypoints <-
                [ (1, 1); (Sim.mapWidthTiles / 2, Sim.mapHeightTiles / 2); (Sim.mapWidthTiles - 3, Sim.mapHeightTiles - 3)
                  (Sim.mapWidthTiles / 2, 60); (Sim.mapWidthTiles / 2, Sim.mapHeightTiles - 60)
                  (80, 200); (430, 300) ]
        if riverscapeTourMode then
            tourWaypoints <- riverscapeTourWaypoints ()
        graphics.PreferredBackBufferWidth <- 1280
        graphics.PreferredBackBufferHeight <- 720
        graphics.SynchronizeWithVerticalRetrace <- true
        this.IsFixedTimeStep <- true
        this.TargetElapsedTime <- TimeSpan.FromTicks(TimeSpan.TicksPerSecond / 60L)
        this.Window.Title <- ChineseText.copy.SceneTitle
        printfn $"mode={modeName} seed=42"
        printfn "controls=WASD move E interact 1-6 choose Q observe Tab needs C chronicle L relations P pause F1/F2/F3 speed F6 save F7 load Esc close/exit"
    member private this.CenterCamera() =
        let viewport = this.GraphicsDevice.Viewport
        let vw = float32 viewport.Width
        let vh = float32 viewport.Height
        let worldW = float32 (Sim.mapWidthTiles * Sim.tilePixels)
        let worldH = float32 (Sim.mapHeightTiles * Sim.tilePixels)
        let half = float32 Sim.tilePixels / 2.0f
        let x = MathHelper.Clamp(world.Avatar.Pos.X + half - vw / 2.0f, 0.0f, max 0.0f (worldW - vw))
        let y = MathHelper.Clamp(world.Avatar.Pos.Y + half - vh / 2.0f, 0.0f, max 0.0f (worldH - vh))
        camera <- Vector2(x, y)

    member private this.ResetWorldView() =
        relationView <- false
        relationSnapshot <- None
        avatarFacing <- VillageArt.SouthFacing
        avatarMoving <- false
        m5View <- M5Interaction.refreshPrompt world M5Interaction.initial
        this.CenterCamera()

    member private this.StartNewGame (occupation: Occupation.Kind option) =
        let startTick = evidenceStartTick ()
        let state =
            occupation
            |> Option.map (fun kind -> WorldBootstrap.occupationStateFor 42UL kind startTick)
        world <-
            initialWorldForMode state
            |> withStartTick
        this.ResetWorldView()
        m5View <- { m5View with Task = state }
        menu <- menu |> MenuState.setCurrentWorld true |> MenuState.enterGame
        let occupationName = occupation |> Option.map Occupation.nameOf |> Option.defaultValue "none"
        printfn $"new-game=ok seed=42 npcs={Sim.npcCount} occupation={occupationName} tick={world.Tick}"

    member private this.SaveWorld (prefix: string) : bool =
        try
            WorldSave.saveToFileWith m5View.Task savePath world
            m5View <- { m5View with Status = "save succeeded"; StatusTick = Some world.Tick }
            printfn $"{prefix}=ok path={savePath} tick={world.Tick}"
            true
        with
        | ex ->
            m5View <- { m5View with Status = "save failed"; StatusTick = Some world.Tick }
            printfn $"{prefix}=error path={savePath} message={ex.Message}"
            false

    member private this.LoadWorld (prefix: string) : Result<int64, string> =
        match WorldSave.loadFromFileWith savePath with
        | Ok (nextWorld, occupation) ->
            world <- nextWorld
            this.ResetWorldView()
            m5View <- { m5View with Task = occupation }
            printfn $"{prefix}=ok path={savePath} tick={world.Tick}"
            Ok world.Tick
        | Error failure ->
            printfn $"{prefix}=error path={savePath} message={failure}"
            Error failure

    member private this.OpenMainMenu() =
        relationView <- false
        relationSnapshot <- None
        m5View <- M5Interaction.initial
        menu <- menu |> MenuState.setCurrentWorld true |> MenuState.openMain
        printfn $"menu=open tick={world.Tick}"

    member private this.ApplyMenuCommand (command: MenuCommand) =
        match command with
        | NoCommand -> ()
        | ContinueGame ->
            menu <- menu |> MenuState.setCurrentWorld true |> MenuState.enterGame
            printfn $"continue=ok tick={world.Tick}"
        | StartNewGame ->
            menu <- MenuState.openOccupationSelect menu
            printfn "menu=occupation-select"
        | StartNewGameWith occupation -> this.StartNewGame occupation
        | LoadGame ->
            match this.LoadWorld "load" with
            | Ok _ ->
                menu <- menu |> MenuState.setCurrentWorld true |> MenuState.enterGame
            | Error failure ->
                menu <- menu |> MenuState.showLoadError failure
        | ApplySettings nextControl ->
            simulationControl <- nextControl
            legacyStepsPerFrame <- None
            menu <- menu |> MenuState.setSettings nextControl
            printfn $"simulation={M6Presentation.clockLabel simulationControl}"
        | ExitGame ->
            printfn "menu=exit"
            this.Exit()

    member private this.DispatchMenuInput (input: MenuInput) =
        let nextMenu, command = MenuState.update input menu
        menu <- nextMenu
        this.ApplyMenuCommand command

    member private this.UpdateMenu (pressed: Keys -> bool) =
        let pressedAny (keys: Keys list) = keys |> List.exists pressed
        let input =
            if pressedAny [ Keys.Up; Keys.W ] then Some Up
            elif pressedAny [ Keys.Down; Keys.S ] then Some Down
            elif pressed Keys.Enter then Some Confirm
            elif pressed Keys.Escape then Some Back
            else None
        match input with
        | Some nextInput -> this.DispatchMenuInput nextInput
        | None when (autoplay || sampleMode) && not autoplayFlow
                    && (menu.Page = MainMenu || menu.Page = OccupationSelect)
                    && not menu.HasCurrentWorld ->
            autoplayFrames <- autoplayFrames + 1
            if autoplayFrames >= 15 then
                this.DispatchMenuInput Confirm
        | None -> ()

    member private this.RunSampleMode () =
        let stageBefore = sampleState.Stage
        let positionBefore = world.Avatar.Pos
        let nextWorld, nextView, nextState = SampleScript.runFrame world m5View sampleState
        if nextWorld.Avatar.Pos <> positionBefore then
            avatarFacing <- VillageArt.facingAfterMovement positionBefore nextWorld.Avatar.Pos avatarFacing
        avatarMoving <- nextWorld.Avatar.Pos <> positionBefore
        world <- nextWorld
        m5View <- nextView
        sampleState <- nextState
        this.CenterCamera()
        if nextState.Stage <> stageBefore then
            printfn $"sample stage={nextState.Stage} tick={nextWorld.Tick} pos=({nextWorld.Avatar.Pos.X:F0},{nextWorld.Avatar.Pos.Y:F0})"
            if nextState.Stage = SampleScript.SampleComplete then
                printfn (if nextState.TimedOut then "sample result=timeout" else "sample result=ok")
                this.Exit()

    /// P16-FIX：菜单截图模式。停在开始界面，按确定性帧表向下切到「读档」，帧表见 MenuShotScript。
    member private this.RunMenuShot () =
        menuShotFrame <- menuShotFrame + 1L
        if menuShotFrame = MenuShotScript.downFrame then
            this.DispatchMenuInput Down

    /// P20 第三步取证：真走位巡游（Sim.step 驱动）沿桥/路/民居门移动，用于桥面行走帧与昼夜录制。
    member private this.RunRiverscapeTour () =
        let target = tourWaypoints.[tourIndex % tourWaypoints.Length]
        let targetPos : Vec2 =
            { X = float32 (fst target * Sim.tilePixels + Sim.tilePixels / 2)
              Y = float32 (snd target * Sim.tilePixels + Sim.tilePixels / 2) }
        let dx = targetPos.X - world.Avatar.Pos.X
        let dy = targetPos.Y - world.Avatar.Pos.Y
        let distance = sqrt (dx * dx + dy * dy)
        if distance < 3.0f then
            tourIndex <- tourIndex + 1
            if tourIndex >= tourWaypoints.Length then
                printfn "riverscape tour=complete frames=%d" recordIndex
                this.Exit()
        else
            let inv = 1.0f / distance
            let input = { Input = { MoveX = dx * inv; MoveY = dy * inv } }
            let before = world.Avatar.Pos
            world <- Sim.step input world
            avatarFacing <- VillageArt.facingAfterMovement before world.Avatar.Pos avatarFacing
            avatarMoving <- distance > 4.0f
        m5View <- M5Interaction.refreshPrompt world m5View
        this.CenterCamera()
        tourFrame <- tourFrame + 1

    member private this.RunMapTour () =
        let (tileX, tileY) = tourWaypoints.[tourIndex % tourWaypoints.Length]
        let position : Vec2 =
            { X = float32 (tileX * Sim.tilePixels + Sim.tilePixels / 2)
              Y = float32 (tileY * Sim.tilePixels + Sim.tilePixels / 2) }
        world <- { world with Avatar = { world.Avatar with Pos = position } }
        // give NPCs active ticks so the town stays alive between waypoints
        for _ in 0 .. 7 do
            world <- Sim.step { Input = { MoveX = 0.0f; MoveY = 0.0f } } world
        avatarFacing <- VillageArt.SouthFacing
        avatarMoving <- false
        m5View <- M5Interaction.refreshPrompt world m5View
        this.CenterCamera()
        tourFrame <- tourFrame + 1
        if tourFrame >= 45 then
            tourFrame <- 0
            tourIndex <- tourIndex + 1
            if tourIndex >= tourWaypoints.Length then
                printfn "map tour=complete frames={recordIndex}"
                this.Exit()
            else
                printfn $"map tour={tourIndex} at tile=({tileX},{tileY})"

    member private this.UpdatePlaying (gameTime: GameTime) (kb: KeyboardState) (pressed: Keys -> bool) (pressedAny: Keys list -> bool) =
        if riverscapeTourMode then
            this.RunRiverscapeTour()
        elif mapTourMode then
            this.RunMapTour()
        elif sampleMode then
            this.RunSampleMode()
        else
            this.UpdatePlayingManual gameTime kb pressed pressedAny

    member private this.UpdatePlayingManual (gameTime: GameTime) (kb: KeyboardState) (pressed: Keys -> bool) (pressedAny: Keys list -> bool) =
        let mutable loadFailed = false
        let mutable leftGame = false
        let lPressed = pressed Keys.L
        let escapePressed = pressed Keys.Escape
        if pressed Keys.P then
            if m5View.Panel = WorldPanel then
                let helpState, pausedControl = MenuState.enterPauseHelp simulationControl menu
                menu <- helpState
                pauseHelpControl <- Some simulationControl
                simulationControl <- pausedControl
                printfn $"help=pause-open simulation={M6Presentation.clockLabel simulationControl}"
        if pressed Keys.F1 then
            simulationControl <- SimulationControl.setSpeed OneX simulationControl
            legacyStepsPerFrame <- None
            menu <- MenuState.setSettings simulationControl menu
            printfn $"simulation={M6Presentation.clockLabel simulationControl}"
        if pressed Keys.F2 then
            simulationControl <- SimulationControl.setSpeed TwoX simulationControl
            legacyStepsPerFrame <- None
            menu <- MenuState.setSettings simulationControl menu
            printfn $"simulation={M6Presentation.clockLabel simulationControl}"
        if pressed Keys.F3 then
            simulationControl <- SimulationControl.setSpeed FiveX simulationControl
            legacyStepsPerFrame <- None
            menu <- MenuState.setSettings simulationControl menu
            printfn $"simulation={M6Presentation.clockLabel simulationControl}"
        if pressed Keys.F6 then
            this.SaveWorld "save" |> ignore
        if pressed Keys.F7 then
            match this.LoadWorld "load" with
            | Ok _ -> menu <- MenuState.setCurrentWorld true menu
            | Error failure ->
                menu <- menu |> MenuState.setCurrentWorld true |> MenuState.showLoadError failure
                loadFailed <- true
        if not loadFailed && escapePressed then
            if m5View.Panel <> WorldPanel then
                let nextWorld, nextView = M5Interaction.apply ClosePanel world m5View
                world <- nextWorld
                m5View <- nextView
                printfn $"m5 panel={M5Interaction.panelName m5View} status={m5View.Status} tick={world.Tick}"
            elif relationView then
                relationView <- false
                relationSnapshot <- None
                printfn $"relation view=off tick={world.Tick}"
            else
                this.OpenMainMenu()
                leftGame <- true
        if not loadFailed && not leftGame then
            if lPressed && M5Interaction.worldInputAllowed m5View then
                relationView <- not relationView
                if relationView then relationSnapshot <- Some(Sim.relationMatrix world)
                let state = if relationView then "on" else "off"
                printfn $"relation view={state} tick={world.Tick}"
            let m5Command =
                if M5Interaction.worldInputAllowed m5View && pressed Keys.E then Some Interact
                elif m5View.Panel = DialoguePanel && pressedAny [ Keys.D1; Keys.NumPad1 ] then Some Intent1
                elif m5View.Panel = DialoguePanel && pressedAny [ Keys.D2; Keys.NumPad2 ] then Some Intent2
                elif m5View.Panel = DialoguePanel && pressedAny [ Keys.D3; Keys.NumPad3 ] then Some Intent3
                elif m5View.Panel = DialoguePanel && pressedAny [ Keys.D4; Keys.NumPad4 ] then Some Intent4
                elif m5View.Panel = DialoguePanel && pressedAny [ Keys.D5; Keys.NumPad5 ] then Some Intent5
                elif m5View.Panel = DialoguePanel && pressedAny [ Keys.D6; Keys.NumPad6 ] then Some Intent6
                elif pressed Keys.Q then Some Observe
                elif pressed Keys.Tab then Some ToggleNeeds
                elif pressed Keys.C then Some ShowChronicle
                elif pressed Keys.T then Some ShowTaskPanel
                else None
            match m5Command with
            | Some command ->
                let nextWorld, nextView = M5Interaction.apply command world m5View
                world <- nextWorld
                m5View <- nextView
                printfn $"m5 panel={M5Interaction.panelName m5View} status={m5View.Status} tick={world.Tick}"
            | None -> ()
            let panelOpen = m5View.Panel <> WorldPanel
            if not relationView && not panelOpen then
                let input =
                    if automated then
                        let t = float32 world.Tick
                        { MoveX = MathF.Sin(t / 60.0f) * 0.8f
                          MoveY = MathF.Cos(t / 90.0f) * 0.6f }
                    else
                        { MoveX =
                            (if kb.IsKeyDown(Keys.D) then 1.0f
                             elif kb.IsKeyDown(Keys.A) then -1.0f
                             else 0.0f)
                          MoveY =
                            (if kb.IsKeyDown(Keys.S) then 1.0f
                             elif kb.IsKeyDown(Keys.W) then -1.0f
                             else 0.0f) }
                let ts = { Input = input }
                let stepCount = SimulationControl.stepsPerFrameWithLegacy legacyStepsPerFrame simulationControl
                if stepCount > 0 then
                    let mutable moved = false
                    for _ in 1 .. stepCount do
                        let previousPosition = world.Avatar.Pos
                        world <- Sim.step ts world
                        avatarFacing <- VillageArt.facingAfterMovement previousPosition world.Avatar.Pos avatarFacing
                        moved <- moved || world.Avatar.Pos <> previousPosition
                    avatarMoving <- moved
                else
                    avatarMoving <- false
                this.CenterCamera()
                match m5View.Task with
                | Some state ->
                    let refreshed = WorldBootstrap.refreshOccupationToday 42UL state world.Tick
                    if refreshed <> state then
                        m5View <- { m5View with Task = Some refreshed }
                | None -> ()
            m5View <- M5Interaction.refreshPrompt world m5View

    member private this.RunAutoplayFlow() =
        let moveDown count =
            for _ in 1 .. count do
                this.DispatchMenuInput Down
        match flowStep with
        | 0 ->
            printfn "flow=main-menu"
            flowStep <- 50
        | 50 when menu.Page = MainMenu ->
            flowHold <- flowHold + 1
            if flowHold >= 60 then
                flowHold <- 0
                this.DispatchMenuInput Confirm
                printfn "flow=new-game"
                flowStep <- 1
        | 50 ->
            printfn "flow=new-game"
            flowStep <- 1
        | 1 when menu.Page = OccupationSelect ->
            this.DispatchMenuInput Confirm
            printfn "flow=occupation=none"
        | 1 when menu.Page = Playing ->
            this.OpenMainMenu()
            printfn "flow=return-menu"
            flowStep <- 2
        | 2 when menu.Page = MainMenu ->
            moveDown 1
            this.DispatchMenuInput Confirm
            printfn "flow=load"
            flowStep <- 3
        | 3 ->
            this.DispatchMenuInput Back
            printfn "flow=back"
            flowStep <- 4
        | 4 when menu.Page = MainMenu ->
            this.SaveWorld "flow=save" |> ignore
            flowStep <- 5
        | 5 when menu.Page = MainMenu ->
            moveDown 1
            this.DispatchMenuInput Confirm
            printfn "flow=load-again"
            flowStep <- 6
        | 6 ->
            this.OpenMainMenu()
            printfn "flow=exit"
            this.Exit()
            flowStep <- 7
        | _ -> ()

    override this.Initialize() =
        base.Initialize()
        prevKb <- Keyboard.GetState()

    override _.LoadContent() =
        spriteBatch <- new SpriteBatch(this.GraphicsDevice)
        artTextures <- VillageArt.loadTextures this.GraphicsDevice
        cjkAtlas <- CjkGlyphAtlas.load this.GraphicsDevice
        pixel <- new Texture2D(this.GraphicsDevice, 1, 1)
        pixel.SetData([| Color.White |])

    override _.UnloadContent() =
        if not (isNull artTextures.TileAtlas) then artTextures.TileAtlas.Dispose()
        if not (isNull artTextures.CharacterAtlas) then artTextures.CharacterAtlas.Dispose()
        if not (isNull artTextures.InteriorAtlas) then artTextures.InteriorAtlas.Dispose()
        if not (isNull cjkAtlas) then cjkAtlas.Dispose()
        if not (isNull pixel) then pixel.Dispose()
        if not (isNull spriteBatch) then spriteBatch.Dispose()

    override this.Update(gameTime: GameTime) =
        let kb = Keyboard.GetState()
        let pressed (key: Keys) = kb.IsKeyDown(key) && not (prevKb.IsKeyDown(key))
        let pressedAny (keys: Keys list) = keys |> List.exists pressed
        if splashActive then
            splashFrame <- splashFrame + 1L
            let skip = LaunchScreen.skipRequested (pressed Keys.Escape) (pressed Keys.Space)
            if skip || LaunchScreen.isComplete splashFrame then
                splashActive <- false
                menuEntranceFrame <- 0L
                printfn (if skip then "splash=skip frame=%d" else "splash=done frame=%d") splashFrame
        else
            if autoplayFlow then
                this.RunAutoplayFlow()
            elif menu.Page = Playing then
                this.UpdatePlaying gameTime kb pressed pressedAny
            elif menuShotMode then
                this.RunMenuShot()
            else
                this.UpdateMenu pressed
            if menu.Page <> Playing then
                menuEntranceFrame <- menuEntranceFrame + 1L
        match pauseHelpControl with
        | Some original when menu.Page = Playing ->
            let _, restoredControl = MenuState.exitPauseHelp original menu
            simulationControl <- restoredControl
            pauseHelpControl <- None
            printfn $"help=pause-close simulation={M6Presentation.clockLabel simulationControl}"
        | _ -> ()
        hudClock <- hudClock + 1L
        if m5View.Status <> hudStatus then
            hudStatus <- m5View.Status
            hudStatusAt <- hudClock
        fpsFrames <- fpsFrames + 1
        fpsSeconds <- fpsSeconds + gameTime.ElapsedGameTime.TotalSeconds
        if fpsSeconds >= 1.0 then
            let fps = float fpsFrames / fpsSeconds
            fpsFrames <- 0
            fpsSeconds <- 0.0
            printfn $"fps={fps:F1} tick={world.Tick} pos=({world.Avatar.Pos.X:F0},{world.Avatar.Pos.Y:F0})"
        prevKb <- kb

    member private this.DrawLine (a: Vector2) (b: Vector2) (thickness: float32) (color: Color) =
        let d = b - a
        let len = d.Length()
        if len > 1.0f then
            let angle = MathF.Atan2(d.Y, d.X)
            spriteBatch.Draw(pixel, a, System.Nullable(), color, angle, Vector2.Zero, Vector2(len, thickness), SpriteEffects.None, 0.0f)

    member private this.DrawRelationView() =
        let profile = M6Presentation.profileAtTick world.Tick
        this.GraphicsDevice.Clear(profile.Background)
        let viewport = this.GraphicsDevice.Viewport
        let vw = float32 viewport.Width
        let vh = float32 viewport.Height
        let mapW = float32 (Sim.mapWidthTiles * Sim.tilePixels)
        let mapH = float32 (Sim.mapHeightTiles * Sim.tilePixels)
        let margin = 48.0f
        let scale = min ((vw - 2.0f * margin) / mapW) ((vh - 2.0f * margin) / mapH)
        let ox = (vw - mapW * scale) / 2.0f
        let oy = (vh - mapH * scale) / 2.0f
        let toScreen (p: Vec2) : Vector2 = Vector2(ox + p.X * scale, oy + p.Y * scale)
        spriteBatch.Begin()
        match relationSnapshot with
        | Some m ->
            let n = Array2D.length1 m
            for i in 0 .. n - 1 do
                for j in i + 1 .. n - 1 do
                    let r = m.[i, j]
                    if abs r > Sim.relationThreshold then
                        let a = toScreen world.Npcs.[i].Pos
                        let b = toScreen world.Npcs.[j].Pos
                        let color = if r > 0.0f then Color.LimeGreen else Color.IndianRed
                        let thickness = Sim.clamp (1.5f + 3.0f * abs r) 1.5f 12.0f
                        this.DrawLine a b thickness color
            for npc in world.Npcs do
                let p = toScreen npc.Pos
                spriteBatch.Draw(pixel, Rectangle(int p.X - 5, int p.Y - 5, 10, 10), Color.Cyan)
        | None -> ()
        spriteBatch.End()

    /// 将当前后台缓冲存为 PNG（取证用；record 与菜单截图共用）。
    member private this.SaveBackBuffer (path: string) =
        let width = this.GraphicsDevice.PresentationParameters.BackBufferWidth
        let height = this.GraphicsDevice.PresentationParameters.BackBufferHeight
        let buffer = Array.zeroCreate<Color> (width * height)
        this.GraphicsDevice.GetBackBufferData<Color>(buffer)
        use texture = new Texture2D(this.GraphicsDevice, width, height)
        texture.SetData(buffer)
        use stream = System.IO.File.Create(path)
        texture.SaveAsPng(stream, width, height)

    /// P16-FIX：按 MenuShotScript 帧表落菜单/启动画面截图，拍完即退出。
    member private this.CaptureMenuShot () =
        let save name =
            System.IO.Directory.CreateDirectory recordDirectory |> ignore
            this.SaveBackBuffer(sprintf "%s/%s.png" recordDirectory name)
        if splashActive then
            if splashFrame = MenuShotScript.splashMidFrame then
                save MenuShotScript.splashMidName
        elif menuShotFrame = MenuShotScript.initialFrame then
            save MenuShotScript.initialName
        elif menuShotFrame = MenuShotScript.loadFrame then
            save MenuShotScript.loadName
        elif menuShotFrame = MenuShotScript.exitFrame then
            printfn "menu-shot=done frames=%d" menuShotFrame
            this.Exit()

    /// P20 证据：把一次 MapGen 绘制渲染到指定尺寸离屏 target，返回绘制瓦片数与纹理。
    member private this.RenderMapGen (targetWidth: int) (targetHeight: int) (camX: int) (camY: int) (drawFitted: bool) : int * Texture2D =
        use target = new RenderTarget2D(this.GraphicsDevice, targetWidth, targetHeight)
        this.GraphicsDevice.SetRenderTarget target
        this.GraphicsDevice.Clear(Color(18, 26, 20))
        spriteBatch.Begin()
        let drawn =
            if drawFitted then
                VillageArt.drawMapFitted spriteBatch artTextures pixel targetWidth targetHeight mapGenResult Color.White
            else
                VillageArt.drawMapViewport spriteBatch artTextures pixel (Vector2(float32 camX, float32 camY)) targetWidth targetHeight mapGenResult 0L Color.White
        spriteBatch.End()
        this.GraphicsDevice.SetRenderTarget null
        let data = Array.zeroCreate<Color> (targetWidth * targetHeight)
        target.GetData<Color>(data)
        let texture = new Texture2D(this.GraphicsDevice, targetWidth, targetHeight)
        texture.SetData(data)
        (drawn, texture)

    /// P20 证据：整图放大渲染（每瓦片 6px）+ 1:1 视口裁剪帧各存一张，打印计数后退出。
    member private this.DrawMapGenShot () =
        System.IO.Directory.CreateDirectory recordDirectory |> ignore
        let viewport = this.GraphicsDevice.Viewport
        let mapCell = 6
        let fittedDrawn, fittedTexture = this.RenderMapGen (mapGenResult.Width * mapCell) (mapGenResult.Height * mapCell) 0 0 true
        use _fitted = fittedTexture
        use stream = System.IO.File.Create(sprintf "%s/p20b-map-%dx%d-seed%d.png" recordDirectory mapGenResult.Width mapGenResult.Height (int mapGenResult.Seed))
        fittedTexture.SaveAsPng(stream, fittedTexture.Width, fittedTexture.Height)
        printfn "mapgen-fitted drawn=%d png=%dx%d" fittedDrawn fittedTexture.Width fittedTexture.Height

        let clampRange maximum value = max 0 (min (max 0 maximum) value)
        let camX = clampRange (mapGenResult.Width * Sim.tilePixels - viewport.Width) ((mapGenResult.Width * Sim.tilePixels - viewport.Width) / 2)
        let camY = clampRange (mapGenResult.Height * Sim.tilePixels - viewport.Height) ((mapGenResult.Height * Sim.tilePixels - viewport.Height) / 2)
        let culledDrawn, culledTexture = this.RenderMapGen viewport.Width viewport.Height camX camY false
        use _culled = culledTexture
        use culledStream = System.IO.File.Create(sprintf "%s/p20b-culled-%dx%d-seed%d.png" recordDirectory mapGenResult.Width mapGenResult.Height (int mapGenResult.Seed))
        culledTexture.SaveAsPng(culledStream, viewport.Width, viewport.Height)
        let total = mapGenResult.Width * mapGenResult.Height
        let visible = MapGen.visibleTileCount mapGenResult.Width mapGenResult.Height camX camY viewport.Width viewport.Height
        printfn "mapgen-cull drawn=%d visible=%d total=%d culled=%.1f%%" culledDrawn visible total (100.0 * (1.0 - float culledDrawn / float total))

        match mapGenResult.Bridges with
        | (bx, by) :: _ ->
            let detailCamX = clampRange (mapGenResult.Width * Sim.tilePixels - viewport.Width) (bx * Sim.tilePixels - viewport.Width / 2)
            let detailCamY = clampRange (mapGenResult.Height * Sim.tilePixels - viewport.Height) (by * Sim.tilePixels - viewport.Height / 2)
            let detailDrawn, detailTexture = this.RenderMapGen viewport.Width viewport.Height detailCamX detailCamY false
            use _detail = detailTexture
            use detailStream = System.IO.File.Create(sprintf "%s/p20b-detail-%dx%d-seed%d.png" recordDirectory mapGenResult.Width mapGenResult.Height (int mapGenResult.Seed))
            detailTexture.SaveAsPng(detailStream, detailTexture.Width, detailTexture.Height)
            printfn "mapgen-detail drawn=%d bridge=(%d,%d) camera=(%d,%d)" detailDrawn bx by detailCamX detailCamY
        | [] -> ()

        let smallWatch = System.Diagnostics.Stopwatch.StartNew()
        let smallMap = MapGen.generateWithSize 64 48 (uint64 4242)
        smallWatch.Stop()
        printfn "mapgen-gen-legacy size=%dx%d gen_ms=%.2f tiles=%d reachable_ok=%b" smallMap.Width smallMap.Height smallWatch.Elapsed.TotalMilliseconds smallMap.Tiles.Length smallMap.ReachabilityOk

        let frameWatch = System.Diagnostics.Stopwatch.StartNew()
        use frameTarget = new RenderTarget2D(this.GraphicsDevice, viewport.Width, viewport.Height)
        this.GraphicsDevice.SetRenderTarget frameTarget
        for _ in 1 .. 30 do
            spriteBatch.Begin()
            VillageArt.drawMapViewport spriteBatch artTextures pixel (Vector2(float32 camX, float32 camY)) viewport.Width viewport.Height mapGenResult 0L Color.White |> ignore
            spriteBatch.End()
        this.GraphicsDevice.SetRenderTarget null
        frameWatch.Stop()
        let perFrameMs = frameWatch.Elapsed.TotalMilliseconds / 30.0
        printfn "mapgen-frame avg_ms=%.2f implied_fps=%.1f iterations=30" perFrameMs (1000.0 / perFrameMs)
        printfn "mapgen-shot=done"
        this.Exit()

    override this.Draw(gameTime: GameTime) =
        if mapGenShotMode then
            this.DrawMapGenShot()
        else
            if splashActive then
                this.DrawSplash()
            elif menu.Page <> Playing then
                this.DrawMenu()
            elif relationView then
                this.DrawRelationView()
                this.DrawM5Overlay()
            else
                this.DrawWorldView()
            if recordMode && sampleMode then
                recordIndex <- recordIndex + 1
                if recordIndex % recordEvery = 0 then
                    System.IO.Directory.CreateDirectory recordDirectory |> ignore
                    this.SaveBackBuffer(sprintf "%s/%s%04d.png" recordDirectory recordName recordIndex)
            if menuShotMode then
                this.CaptureMenuShot()

    /// 启动画面：分层天色 + 屋脊/水面剪影 + 标题淡入上浮 + 跳过提示，全部为帧计数纯函数。
    member private this.DrawSplash() =
        let viewport = this.GraphicsDevice.Viewport
        let width = viewport.Width
        let height = viewport.Height
        let layout = TitleScreen.layout width height
        let reveal = LaunchScreen.revealProgress splashFrame
        let veil = LaunchScreen.veilAlpha splashFrame
        let alpha (value: int) = int (float32 value * reveal)
        spriteBatch.Begin()

        // 分层天色：沿用标题画面色带，绝不整屏纯色或大黑块。
        let bandCount = List.length layout.SkyBands
        let bandHeight = height / bandCount
        List.iteri (fun index (band: TitleScreen.ColorRgb) ->
            let y0 = index * bandHeight
            let y1 = if index = bandCount - 1 then height else y0 + bandHeight
            spriteBatch.Draw(pixel, Rectangle(0, y0, width, y1 - y0), Color(band.R, band.G, band.B))) layout.SkyBands

        // 屋脊剪影随暗幕退场而上浮就位。
        let drop = int (28.0f * veil)
        for x in 0 .. Sim.tilePixels .. width - 1 do
            spriteBatch.Draw(artTextures.TileAtlas, Rectangle(x, layout.RidgeY + drop, Sim.tilePixels, Sim.tilePixels), VillageArt.atlasTileRectangle (fst TitleScreen.roofSlots), Color.White)
            spriteBatch.Draw(artTextures.TileAtlas, Rectangle(x, layout.EaveY + drop, Sim.tilePixels, Sim.tilePixels), VillageArt.atlasTileRectangle (snd TitleScreen.roofSlots), Color.White)

        // 水面色带反射天色，随显现度提高而淡出。
        let waterColor = Color(150, 170, 178, int (255.0f * (1.0f - reveal)))
        for row in layout.WaterRows do
            for x in 0 .. Sim.tilePixels .. width - 1 do
                spriteBatch.Draw(artTextures.TileAtlas, Rectangle(x, row, Sim.tilePixels, Sim.tilePixels), VillageArt.atlasTileRectangle TitleScreen.waterSlot, waterColor)

        // 标题：淡入 + 上浮，先画深色投影再画亮面。
        let titleRise = int (24.0f * (1.0f - reveal))
        PixelText.draw spriteBatch pixel cjkAtlas (layout.TitleX + 4) (layout.TitleY + titleRise + 4) layout.TitleScale (Color(12, 20, 28, alpha 255)) LaunchScreen.title
        PixelText.draw spriteBatch pixel cjkAtlas layout.TitleX (layout.TitleY + titleRise) layout.TitleScale (Color(235, 246, 232, alpha 255)) LaunchScreen.title

        // 英文副标题保持同一 CJK/点阵字体路径。
        let subtitleScale = 2
        let subtitleWidth = FloatingPrompt.measureWidth LaunchScreen.subtitle subtitleScale
        PixelText.draw spriteBatch pixel cjkAtlas ((width - subtitleWidth) / 2) (layout.TitleY + 78) subtitleScale (Color(180, 210, 214, alpha 255)) LaunchScreen.subtitle

        // 跳过提示：轻微呼吸闪烁，落在底部独立窄条上（非整屏黑块）。
        let blink = if (splashFrame / 20L) % 2L = 0L then 220 else 130
        let hintScale = 2
        let hintWidth = FloatingPrompt.measureWidth LaunchScreen.skipHint hintScale
        let hintX = (width - hintWidth) / 2
        let hintY = height - 56
        spriteBatch.Draw(pixel, Rectangle(hintX - 10, hintY - 8, hintWidth + 20, 8 * hintScale + 16), Color(10, 16, 24, int (170.0f * (0.5f + 0.5f * reveal))))
        spriteBatch.Draw(pixel, Rectangle(hintX - 10, hintY - 8, hintWidth + 20, 2), Color(92, 180, 190, alpha 220))
        PixelText.draw spriteBatch pixel cjkAtlas hintX hintY hintScale (Color(220, 235, 225, alpha blink)) LaunchScreen.skipHint
        spriteBatch.End()

    member private this.DrawMenu() =
        let viewport = this.GraphicsDevice.Viewport
        let width = viewport.Width
        let height = viewport.Height
        let layout = TitleScreen.layout width height
        let panelWidth = layout.PanelWidth
        let panelX = layout.PanelX
        let panelY = layout.PanelY
        let contentRows =
            match menu.Page with
            | MainMenu -> MenuState.items menu |> List.length
            | OccupationSelect -> MenuState.occupationOptions.Length
            | Settings -> MenuState.settings.Length
            | Controls -> MenuState.controlRows.Length
            | LoadError -> 4
            | Playing -> 0
        let rowHeight = if menu.Page = Controls then 25 else layout.MenuLineHeight
        let panelY =
            if menu.Page = Controls then layout.ControlsPanelY else layout.PanelY
        let panelHeight =
            min (height - panelY - 16)
                (max layout.PanelHeight (120 + contentRows * rowHeight + 48))
        let innerX = layout.MenuX
        let textScale = 2
        let lineHeight = layout.MenuLineHeight
        let selectedColor = Color(245, 222, 120)
        let textColor = Color(210, 226, 220)
        let mutedColor = Color(140, 170, 170)
        let drawText (x: int) (y: int) (color: Color) (text: string) =
            PixelText.draw spriteBatch pixel cjkAtlas x y textScale color text
        let drawSelection (index: int) (label: string) (y: int) =
            let selected = index = menu.Selected
            let cursor, labelRect = TitleScreen.selectionRects layout index
            if selected then
                PixelText.draw spriteBatch pixel cjkAtlas cursor.X cursor.Y textScale selectedColor ">"
            else
                PixelText.draw spriteBatch pixel cjkAtlas cursor.X cursor.Y textScale mutedColor " "
            PixelText.draw spriteBatch pixel cjkAtlas labelRect.X labelRect.Y textScale (if selected then selectedColor else textColor) label
        spriteBatch.Begin()

        // Layered dusk gradient: sky bands darken toward the horizon, never a flat block.
        let bandCount = List.length layout.SkyBands
        let bandHeight = height / bandCount
        List.iteri (fun index (band: TitleScreen.ColorRgb) ->
            let y0 = index * bandHeight
            let y1 = if index = bandCount - 1 then height else y0 + bandHeight
            spriteBatch.Draw(pixel, Rectangle(0, y0, width, y1 - y0), Color(band.R, band.G, band.B))) layout.SkyBands

        // Deterministic 2s entrance: skyline settles from above as the progress unwinds.
        let entrance = TitleScreen.entranceProgress menuEntranceFrame
        let skylineDrop = int (36.0f * entrance)
        List.iteri (fun column slot ->
            let x = column * Sim.tilePixels
            let source = VillageArt.atlasTileRectangle slot
            if slot = fst TitleScreen.roofSlots then
                spriteBatch.Draw(artTextures.TileAtlas, Rectangle(x, layout.RidgeY + skylineDrop, Sim.tilePixels, Sim.tilePixels), source, Color.White)
            spriteBatch.Draw(artTextures.TileAtlas, Rectangle(x, layout.EaveY + skylineDrop, Sim.tilePixels, Sim.tilePixels), VillageArt.atlasTileRectangle (snd TitleScreen.roofSlots), Color.White))
            layout.RoofTileSlots

        // Water band drawn from the atlas water tile, reflecting the skyline above.
        let waterColor = Color(150, 170, 178, int (255.0f * (1.0f - entrance)))
        for row in layout.WaterRows do
            for x in 0 .. Sim.tilePixels .. width - 1 do
                spriteBatch.Draw(artTextures.TileAtlas, Rectangle(x, row, Sim.tilePixels, Sim.tilePixels), VillageArt.atlasTileRectangle TitleScreen.waterSlot, waterColor)

        // Lantern glows along the water bank.
        let lanternColor, lanternHalo = TitleScreen.lanternColors
        for (lx, ly) in layout.Lanterns do
            spriteBatch.Draw(pixel, Rectangle(lx - 8, ly - 8, 24, 24), Color(lanternHalo.R, lanternHalo.G, lanternHalo.B, 70))
            spriteBatch.Draw(pixel, Rectangle(lx - 3, ly - 5, 8, 10), Color(lanternColor.R, lanternColor.G, lanternColor.B))
            spriteBatch.Draw(pixel, Rectangle(lx - 1, ly - 7, 4, 2), Color(90, 60, 40))
            spriteBatch.Draw(pixel, Rectangle(lx - 2, ly + 5, 6, 2), Color(90, 60, 40))

        // Title rises into place as the entrance progress unwinds.
        let titleLift = int (24.0f * entrance)
        PixelText.draw spriteBatch pixel cjkAtlas (layout.TitleX + 4) (layout.TitleY + titleLift + 4) layout.TitleScale (Color(12, 20, 28)) layout.TitleText
        PixelText.draw spriteBatch pixel cjkAtlas layout.TitleX (layout.TitleY + titleLift) layout.TitleScale (Color(235, 246, 232)) layout.TitleText

        // Menu panel floats over the lower half; translucent so the scene layers stay visible.
        spriteBatch.Draw(pixel, Rectangle(panelX, panelY, panelWidth, panelHeight), Color(11, 19, 27, 200))
        spriteBatch.Draw(pixel, Rectangle(panelX, panelY, panelWidth, 4), Color(92, 180, 190))
        let contentY = panelY + 60
        let headingY = panelY + 20
        match menu.Page with
        | MainMenu ->
            drawText innerX headingY mutedColor (ChineseText.menuHeading MainMenuHeading)
            MenuState.items menu
            |> List.iteri (fun index item -> drawSelection index (MenuState.itemLabel item) (contentY + index * lineHeight))
            drawText innerX (panelY + panelHeight - 40) mutedColor "UP DOWN 选择 ENTER 确认"
        | OccupationSelect ->
            drawText innerX headingY mutedColor "选择职业"
            MenuState.occupationOptions
            |> List.iteri (fun index occupation ->
                drawSelection index (MenuState.occupationLabel occupation) (contentY + index * lineHeight))
            drawText innerX (panelY + panelHeight - 40) mutedColor "UP DOWN 选择 ENTER 确认 ESC 返回"
        | Settings ->
            drawText innerX headingY mutedColor (ChineseText.menuHeading SettingsHeading)
            MenuState.settings
            |> List.iteri (fun index setting -> drawSelection index (MenuState.settingsLabel setting) (contentY + index * lineHeight))
            drawText innerX (panelY + panelHeight - 72) mutedColor (sprintf "当前 %s" (M6Presentation.clockLabel menu.Settings))
            drawText innerX (panelY + panelHeight - 40) mutedColor "ENTER 应用 ESC 返回"
        | Controls ->
            drawText innerX headingY mutedColor (ChineseText.menuHeading ControlsHeading)
            MenuState.controlRows
            |> List.iteri (fun index row ->
                let keyRect, actionRect = TitleScreen.controlRowRects layout index
                PixelText.draw spriteBatch pixel cjkAtlas keyRect.X keyRect.Y textScale textColor row.Keys
                PixelText.draw spriteBatch pixel cjkAtlas actionRect.X actionRect.Y textScale textColor row.Action)
            drawText innerX (panelY + panelHeight - 40) mutedColor "ESC 返回"
        | LoadError ->
            drawText innerX headingY (Color(240, 130, 120)) "读取失败"
            let message = menu.Error |> Option.defaultValue "暂无存档"
            let visible = if message.Length > 24 then message.Substring(0, 24) else message
            drawText innerX contentY textColor visible
            drawText innerX (contentY + lineHeight * 2) mutedColor "ENTER ESC 返回"
        | Playing -> ()
        spriteBatch.End()

    member private this.DrawWorldView() =
        let profile = M6Presentation.profileAtTick world.Tick
        let viewport = this.GraphicsDevice.Viewport
        this.GraphicsDevice.Clear(profile.Background)
        spriteBatch.Begin()
        match m5View.HomeMode with
        | Inside _ ->
            VillageArt.drawInterior spriteBatch pixel artTextures viewport.Width viewport.Height renderPlan.Interior profile.WorldTint
            let interiorAvatarSpec = VillageArt.avatarSpriteSpec avatarFacing avatarMoving world.Tick
            VillageArt.drawInteriorCharacter spriteBatch artTextures viewport.Width viewport.Height world.Avatar.Pos interiorAvatarSpec profile.WorldTint
        | Outside ->
            VillageArt.drawWorld
                spriteBatch
                artTextures
                pixel
                camera
                viewport.Width
                viewport.Height
                renderPlan
                riverscapeMap
                world.Tick
                profile.WorldTint

            // Warm lantern glows strengthen as night falls (pure function of tick phase).
            // Concentric premultiplied circles fall off radially from each lantern tile, so
            // the core stays a soft warm disc instead of saturating into a white block, and
            // no glow is painted where there is no lantern entity. 生成器世界用桥头灯笼。
            if profile.LanternGlow > 0.3f then
                let glow = profile.LanternGlow
                let peakAlpha = int (140.0f * glow)
                let lanternTiles =
                    match riverscapeMap with
                    | Some map -> VillageArt.bridgeLanternTiles map
                    | None ->
                        renderPlan.Props
                        |> List.choose (fun prop ->
                            match prop.Kind with
                            | VillageArt.RenderPropKind.RiverLantern ->
                                let position = VillageArt.worldTile renderPlan prop.Position
                                Some(position.X, position.Y)
                            | _ -> None)
                for (tileX, tileY) in lanternTiles do
                    let centerX = tileX * Sim.tilePixels - int camera.X + Sim.tilePixels / 2
                    let centerY = tileY * Sim.tilePixels - int camera.Y + Sim.tilePixels / 2
                    for (rect, color) in VillageArt.lanternGlowLayers centerX centerY 44 6 255 214 150 peakAlpha do
                        spriteBatch.Draw(pixel, rect, color)

            VillageArt.drawGroundShadow spriteBatch pixel camera world.Avatar.Pos
            let avatarSpec = VillageArt.avatarSpriteSpec avatarFacing avatarMoving world.Tick
            VillageArt.drawCharacter spriteBatch artTextures camera world.Avatar.Pos avatarSpec profile.WorldTint

            for npc in world.Npcs do
                VillageArt.drawGroundShadow spriteBatch pixel camera npc.Pos
                let spec = VillageArt.npcSpriteSpecAtTarget npc.Id npc.Pos npc.Mind.Target world.Tick
                VillageArt.drawCharacter spriteBatch artTextures camera npc.Pos spec profile.WorldTint

            // Golden-hour wash: the multiplicative WorldTint can only darken, so a warm
            // premultiplied veil is layered over the whole scene. Because rgb is premultiplied
            // by its own low alpha it adds warm light without ever saturating to white; alpha
            // is a pure tick function, so noon/midnight get none and dawn/dusk peak warm.
            let veilAlpha = M6Presentation.goldenVeilAlpha world.Tick
            if veilAlpha > 0 then
                spriteBatch.Draw(pixel, Rectangle(0, 0, viewport.Width, viewport.Height), VillageArt.premultiply 255 150 70 veilAlpha)
        spriteBatch.End()

        // Contextual floating prompt over the unique target; same CJK atlas font path as the HUD.
        if m5View.Panel = M5Panel.WorldPanel && menu.Page = Playing then
            match m5View.Prompt, m5View.PromptTargetPos with
            | Some text, Some targetPos ->
                let scale = 2
                let rect = FloatingPrompt.layout viewport.Width viewport.Height targetPos.X targetPos.Y camera.X camera.Y scale text
                spriteBatch.Begin()
                spriteBatch.Draw(pixel, Rectangle(rect.X - 6, rect.Y - 5, rect.Width + 12, rect.Height + 8), Color(15, 19, 25, 200))
                spriteBatch.Draw(pixel, Rectangle(rect.X - 6, rect.Y - 5, rect.Width + 12, 2), Color(92, 180, 190))
                PixelText.draw spriteBatch pixel cjkAtlas rect.X rect.Y scale (Color(240, 250, 240)) text
                spriteBatch.End()
            | _ -> ()
        this.DrawM5Overlay()

    member private this.DrawM5Overlay() =
        this.DrawHudBar()
        if m5View.Panel = WorldPanel then
            this.DrawTransientStatus()
        else
            this.DrawPanel()

    /// 顶部窄信息条：时段/时间/倍速/体力/钱币，半透明渐变 + 强调线，绝非大黑块。
    member private this.DrawHudBar() =
        let viewport = this.GraphicsDevice.Viewport
        let profile = M6Presentation.profileAtTick world.Tick
        let palette = HudLayout.palette profile.Mode
        let placed = HudLayout.layout (HudLayout.segments world simulationControl)
        let barHeight = HudLayout.barHeight
        let textY = (barHeight - 8 * HudLayout.textScale) / 2
        spriteBatch.Begin()
        // 竖向渐变：上半略亮、下半压暗，避免整条纯色。
        spriteBatch.Draw(pixel, Rectangle(0, 0, viewport.Width, barHeight / 2), palette.BarTop)
        spriteBatch.Draw(pixel, Rectangle(0, barHeight / 2, viewport.Width, barHeight - barHeight / 2), palette.BarBottom)
        spriteBatch.Draw(pixel, Rectangle(0, barHeight, viewport.Width, HudLayout.accentHeight), palette.Accent)
        for (x, _, segment) in placed do
            PixelText.draw spriteBatch pixel cjkAtlas x textY HudLayout.textScale palette.Label segment.Label
            let labelAdvanced = FloatingPrompt.measureWidth (segment.Label + " ") HudLayout.textScale
            PixelText.draw spriteBatch pixel cjkAtlas (x + labelAdvanced) textY HudLayout.textScale palette.Value segment.Value
        spriteBatch.End()

    /// 常驻情境状态：顶部条下方的小药丸，仅 WorldPanel 且瞬态未过期时出现。
    member private this.DrawTransientStatus() =
        let viewport = this.GraphicsDevice.Viewport
        let statusView = { m5View with StatusTick = Some hudStatusAt }
        match M5Interaction.transientStatusLine hudClock statusView with
        | None -> ()
        | Some line ->
            let scale = 2
            let width = FloatingPrompt.measureWidth line scale
            let x = 16
            let y = HudLayout.barHeight + HudLayout.accentHeight + 8
            spriteBatch.Begin()
            spriteBatch.Draw(pixel, Rectangle(x - 8, y - 6, width + 16, 8 * scale + 12), Color(16, 26, 32, 200))
            spriteBatch.Draw(pixel, Rectangle(x - 8, y - 6, 2, 8 * scale + 12), Color(92, 180, 190))
            PixelText.draw spriteBatch pixel cjkAtlas x y scale (Color(232, 242, 232)) line
            spriteBatch.End()

    /// 打开的面板（对话/需求/观察/年鉴/任务）：底部左侧轻量渐变板，沿用既有 panelLines。
    member private this.DrawPanel() =
        let viewport = this.GraphicsDevice.Viewport
        let textScale = 2
        let lineHeight = 18
        let lines = M5Interaction.panelLines world m5View
        let panelWidth = min 380 (max 1 (viewport.Width - 32))
        let maxLines = max 1 ((viewport.Height - HudLayout.barHeight - 48) / lineHeight)
        let visibleLines = lines |> List.truncate maxLines
        let panelHeight = visibleLines.Length * lineHeight + 26
        let panelX = 16
        let panelY = max (HudLayout.barHeight + 12) (viewport.Height - panelHeight - 16)
        let innerX = panelX + 12
        let innerWidth = max 1 (panelWidth - 24)
        let maxChars = max 1 (innerWidth / (6 * textScale))
        spriteBatch.Begin()
        // 竖向渐变板（半透明，非纯黑），顶部与左侧各一条强调线。
        spriteBatch.Draw(pixel, Rectangle(panelX, panelY, panelWidth, panelHeight / 2), Color(30, 44, 52, 190))
        spriteBatch.Draw(pixel, Rectangle(panelX, panelY + panelHeight / 2, panelWidth, panelHeight - panelHeight / 2), Color(16, 24, 30, 190))
        spriteBatch.Draw(pixel, Rectangle(panelX, panelY, panelWidth, 3), Color(92, 180, 190))
        spriteBatch.Draw(pixel, Rectangle(panelX, panelY, 2, panelHeight), Color(92, 180, 190, 160))
        visibleLines
        |> List.iteri (fun index line ->
            let visible = if line.Length > maxChars then line.Substring(0, maxChars) else line
            let color = if index = 0 then Color(226, 238, 226) else Color(192, 208, 212)
            PixelText.draw spriteBatch pixel cjkAtlas innerX (panelY + 13 + index * lineHeight) textScale color visible)
        spriteBatch.End()