feat(desktop): P16 启动画面淡入（Esc/空格跳过）+ 开始界面收敛三项（开始/读档/退出）+ CJK 补字 238

1 files changed, 82 insertions, 28 deletions

diff --git a/src/LivingVillage.Desktop/Game.fs b/src/LivingVillage.Desktop/Game.fs
index 1b9508b..8402a72 100644
--- a/src/LivingVillage.Desktop/Game.fs
+++ b/src/LivingVillage.Desktop/Game.fs
@@ -140,6 +140,9 @@ type LivingVillageGame() as this =
     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 autoplayFrames = 0
     let mutable flowStep = 0
     let mutable flowHold = 0
@@ -481,34 +484,21 @@ type LivingVillageGame() as this =
             printfn "flow=return-menu"
             flowStep <- 2
         | 2 when menu.Page = MainMenu ->
-            moveDown 3
+            moveDown 1
             this.DispatchMenuInput Confirm
-            printfn "flow=settings=open"
-            this.DispatchMenuInput Down
-            this.DispatchMenuInput Confirm
-            this.DispatchMenuInput Back
-            printfn "flow=settings=back"
+            printfn "flow=load"
             flowStep <- 3
-        | 3 when menu.Page = MainMenu ->
-            moveDown 4
-            this.DispatchMenuInput Confirm
-            printfn "flow=controls=open"
-            flowStep <- 30
-        | 30 ->
-            flowHold <- flowHold + 1
-            if flowHold >= 60 || menu.Page <> Controls then
-                flowHold <- 0
-                flowStep <- 31
-        | 31 ->
+        | 3 ->
             this.DispatchMenuInput Back
-            printfn "flow=controls=back"
+            printfn "flow=back"
             flowStep <- 4
         | 4 when menu.Page = MainMenu ->
-            this.DispatchMenuInput Confirm
             this.SaveWorld "flow=save" |> ignore
             flowStep <- 5
-        | 5 when menu.Page = Playing ->
-            this.LoadWorld "flow=load" |> ignore
+        | 5 when menu.Page = MainMenu ->
+            moveDown 1
+            this.DispatchMenuInput Confirm
+            printfn "flow=load-again"
             flowStep <- 6
         | 6 ->
             this.OpenMainMenu()
@@ -540,12 +530,22 @@ type LivingVillageGame() as this =
         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 autoplayFlow then
-            this.RunAutoplayFlow()
-        elif menu.Page = Playing then
-            this.UpdatePlaying gameTime kb pressed pressedAny
+        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
-            this.UpdateMenu pressed
+            if autoplayFlow then
+                this.RunAutoplayFlow()
+            elif menu.Page = Playing then
+                this.UpdatePlaying gameTime kb pressed pressedAny
+            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
@@ -606,7 +606,9 @@ type LivingVillageGame() as this =
         spriteBatch.End()
 
     override this.Draw(gameTime: GameTime) =
-        if menu.Page <> Playing then
+        if splashActive then
+            this.DrawSplash()
+        elif menu.Page <> Playing then
             this.DrawMenu()
         elif relationView then
             this.DrawRelationView()
@@ -629,6 +631,58 @@ type LivingVillageGame() as this =
                 use stream = System.IO.File.Create(path)
                 texture.SaveAsPng(stream, width, height)
 
+    /// 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
@@ -678,7 +732,7 @@ type LivingVillageGame() as this =
             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 hudClock
+        let entrance = TitleScreen.entranceProgress menuEntranceFrame
         let skylineDrop = int (36.0f * entrance)
         List.iteri (fun column slot ->
             let x = column * Sim.tilePixels