1 files changed, 53 insertions, 0 deletions
diff --git a/src/LivingVillage.Desktop/Interaction.fs b/src/LivingVillage.Desktop/Interaction.fs
index 3a65e8e..5281180 100644
--- a/src/LivingVillage.Desktop/Interaction.fs
+++ b/src/LivingVillage.Desktop/Interaction.fs
@@ -211,6 +211,59 @@ module FloatingPrompt =
         let y = max topSafe (min bottomSafe screenY)
         { X = x; Y = y; Width = width; Height = height }
 
+    /// P77：锚定提示支持长文本折行（逐字、不丢字），供真实用例（如「E 与河边的货郎交谈并查看货品」）。
+    let maxPromptWidth = 360
+
+    type PromptLayout =
+        { Lines: string list
+          X: int
+          Y: int
+          Width: int
+          Height: int }
+
+    let wrapText (maxWidth: int) (scale: int) (text: string) : string list =
+        if text = "" then
+            [ "" ]
+        else
+            let builder = System.Text.StringBuilder()
+            let mutable lines = []
+            for ch in text.ToCharArray() do
+                let candidate = builder.ToString() + string ch
+                if builder.Length > 0 && measureWidth candidate scale > maxWidth then
+                    lines <- builder.ToString() :: lines
+                    builder.Clear() |> ignore
+                    builder.Append(ch) |> ignore
+                else
+                    builder.Append(ch) |> ignore
+            lines <- builder.ToString() :: lines
+            List.rev lines
+
+    /// 锚定点的多行提示版式：按需折行、水平居中于目标、垂直钳制在两条 HUD 带之间。
+    let layoutWrapped
+        (viewportWidth: int)
+        (viewportHeight: int)
+        (anchorWorldX: float32)
+        (anchorWorldY: float32)
+        (cameraX: float32)
+        (cameraY: float32)
+        (scale: int)
+        (text: string) : PromptLayout =
+        let margin = 8
+        let wrapWidth = min maxPromptWidth (max 80 (viewportWidth - 2 * margin))
+        let lines = wrapText wrapWidth scale text
+        let width = lines |> List.map (fun line -> measureWidth line scale) |> List.max
+        let lineHeight = 8 * scale + 4
+        let height = lines.Length * lineHeight + 10
+        let screenX = int anchorWorldX - int cameraX - width / 2
+        let screenY = int anchorWorldY - int cameraY - 24 - height
+        let x =
+            if width + margin * 2 > viewportWidth then margin
+            else max margin (min (viewportWidth - margin - width) screenX)
+        let topSafe = hudTopBarHeight + margin
+        let bottomSafe = max topSafe (viewportHeight - hudBottomBandHeight - height - margin)
+        let y = max topSafe (min bottomSafe screenY)
+        { Lines = lines; X = x; Y = y; Width = width; Height = height }
+
 module M5Interaction =
 
     let initial : M5View =