修改浮漂和绳子逻辑

Assets/Scripts/Fishing/Rope/Rope.cs

@@ -85,6 +85,12 @@ public class Rope : MonoBehaviour
     [SerializeField, Range(1, 8), Tooltip("每隔多少次FixedUpdate更新一次水面约束")]
     private int waterUpdateEvery = 1;
 
+    [SerializeField, Range(0f, 1f), Tooltip("水面约束抬升强度（每次更新的插值强度），越小越渐进")]
+    private float waterLiftStrength = 0.25f;
+
+    [SerializeField, Tooltip("startAnchor 在水下时，让其相邻端节点强制跟随 startAnchor，避免被抬到水面导致脱离")]
+    private bool keepStartAdjacentNodeFollow = true;
+
     [SerializeField, Range(0, 8), Tooltip("水面约束后，再做几次长度约束，减少局部折角")]
     private int waterPostConstraintIterations = 2;
 
@@ -201,6 +207,7 @@ public class Rope : MonoBehaviour
         waterSampleStep = Mathf.Max(1, waterSampleStep);
         waterUpdateEvery = Mathf.Max(1, waterUpdateEvery);
         waterSurfaceOffset = Mathf.Max(0f, waterSurfaceOffset);
+        waterLiftStrength = Mathf.Clamp01(waterLiftStrength);
         waterPostConstraintIterations = Mathf.Clamp(waterPostConstraintIterations, 0, 8);
     }
 
@@ -630,16 +637,18 @@ public class Rope : MonoBehaviour
 
         int step = Mathf.Max(1, waterSampleStep);
         float surfaceY = waterLevelY + waterSurfaceOffset;
+        bool startUnderWater = _pCurr[0].y < surfaceY;
+        int startAdjacentIdx = GetStartAdjacentNodeIndex(last);
 
         int prevSampleIdx = 1;
         float prevSurfaceY = surfaceY;
 
-        ApplyWaterSurface(prevSampleIdx, prevSurfaceY);
+        ApplyWaterSurface(prevSampleIdx, prevSurfaceY, startUnderWater, startAdjacentIdx);
 
         for (int i = 1 + step; i < last; i += step)
         {
             float nextSurfaceY = surfaceY;
-            ApplyWaterSurface(i, nextSurfaceY);
+            ApplyWaterSurface(i, nextSurfaceY, startUnderWater, startAdjacentIdx);
 
             if (waterInterpolate)
             {
@@ -651,13 +660,13 @@ public class Rope : MonoBehaviour
                     int idx = a + j;
                     float t = j / (float)span;
                     float y = Mathf.Lerp(prevSurfaceY, nextSurfaceY, t);
-                    ApplyWaterSurface(idx, y);
+                    ApplyWaterSurface(idx, y, startUnderWater, startAdjacentIdx);
                 }
             }
             else
             {
                 for (int idx = prevSampleIdx + 1; idx < i; idx++)
-                    ApplyWaterSurface(idx, prevSurfaceY);
+                    ApplyWaterSurface(idx, prevSurfaceY, startUnderWater, startAdjacentIdx);
             }
 
             prevSampleIdx = i;
@@ -665,20 +674,38 @@ public class Rope : MonoBehaviour
         }
 
         for (int i = prevSampleIdx + 1; i < last; i++)
-            ApplyWaterSurface(i, prevSurfaceY);
+            ApplyWaterSurface(i, prevSurfaceY, startUnderWater, startAdjacentIdx);
     }
 
-    private void ApplyWaterSurface(int i, float surfaceY)
+    private int GetStartAdjacentNodeIndex(int last)
     {
+        if (last <= 1) return 1;
+
+        Vector3 s = _pCurr[0];
+        float d1 = (_pCurr[1] - s).sqrMagnitude;
+        float d2 = (_pCurr[last - 1] - s).sqrMagnitude;
+        return d1 <= d2 ? 1 : last - 1;
+    }
+
+    private void ApplyWaterSurface(int i, float surfaceY, bool startUnderWater, int startAdjacentIdx)
+    {
+        if (keepStartAdjacentNodeFollow && startUnderWater && i == startAdjacentIdx)
+        {
+            Vector3 s = _pCurr[0];
+            _pCurr[i] = s;
+            _pPrev[i] = s;
+            return;
+        }
+
         Vector3 p = _pCurr[i];
         if (p.y < surfaceY)
         {
-            p.y = surfaceY;
+            p.y = Mathf.Lerp(p.y, surfaceY, waterLiftStrength);
             _pCurr[i] = p;
 
-            // 同步 prev，杀掉向下惯性，避免反复穿透水面
+            // 渐进同步 prev，削弱向下惯性，避免反复穿透水面
             Vector3 prev = _pPrev[i];
-            if (prev.y < surfaceY) prev.y = surfaceY;
+            if (prev.y < p.y) prev.y = Mathf.Lerp(prev.y, p.y, waterLiftStrength);
             _pPrev[i] = prev;
         }
     }
@@ -798,4 +825,4 @@ public class Rope : MonoBehaviour
         for (int i = 0; i < _physicsNodes; i++)
             Gizmos.DrawSphere(_pCurr[i], 0.01f);
     }
-}
+}