将Spline移出Plugin，以调整SplineRenderer的OnWillCameraRender

Assets/Dreamteck/Splines/Components/Sample Modifiers/RotationModifier.cs

@@ -0,0 +1,76 @@
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+namespace Dreamteck.Splines
+{
+    [System.Serializable]
+    public class RotationModifier : SplineSampleModifier
+    {
+        [System.Serializable]
+        public class RotationKey : Key
+        {
+            public bool useLookTarget = false;
+            public Transform target = null;
+            public Vector3 rotation = Vector3.zero;
+
+            public RotationKey(Vector3 rotation, double f, double t) : base(f, t)
+            {
+                this.rotation = rotation;
+            }
+        }
+
+        public override bool hasKeys => keys.Length > 0;
+        public RotationKey[] keys = new RotationKey[0];
+
+        public RotationModifier()
+        {
+            keys = new RotationKey[0];
+        }
+
+        public override List<Key> GetKeys()
+        {
+            return new List<Key>(keys);
+        }
+
+        public override void SetKeys(List<Key> input)
+        {
+            keys = new RotationKey[input.Count];
+            for (int i = 0; i < input.Count; i++)
+            {
+                keys[i] = (RotationKey)input[i];
+            }
+            base.SetKeys(input);
+        }
+
+        public void AddKey(Vector3 rotation, double f, double t)
+        {
+            ArrayUtility.Add(ref keys, new RotationKey(rotation, f, t));
+        }
+
+        public override void Apply(ref SplineSample result)
+        {
+            if (keys.Length == 0) return;
+            base.Apply(ref result);
+
+            Quaternion offset = Quaternion.identity, look = result.rotation;
+            for (int i = 0; i < keys.Length; i++)
+            {
+                if (keys[i].useLookTarget && keys[i].target != null)
+                {
+                    Quaternion lookDir = Quaternion.LookRotation(keys[i].target.position - result.position);
+                    look = Quaternion.Slerp(look, lookDir, keys[i].Evaluate(result.percent) * blend);
+                }
+                else
+                {
+                    Quaternion euler = Quaternion.Euler(keys[i].rotation.x, keys[i].rotation.y, keys[i].rotation.z);
+                    offset = Quaternion.Slerp(offset, offset * euler, keys[i].Evaluate(result.percent) * blend);
+                }
+            }
+            Quaternion rotation = look * offset;
+            Vector3 invertedNormal = Quaternion.Inverse(result.rotation) * result.up;
+            result.forward = rotation * Vector3.forward;
+            result.up = rotation * invertedNormal;
+        }
+    }
+}