fix: 优化了MainCamera脚本的性能

Assets/CameraBehaviour.cs

@@ -9,7 +9,6 @@ public class CameraBehaviour : MonoBehaviour
     private const int MouseZoomMax = 20; //相机距离最大值
     private const float XSpeed = 250.0f;
     private const float YSpeed = 120.0f;
-
     private const int YMinLimit = -360;
     private const int YMaxLimit = 360;
 
@@ -23,11 +22,11 @@ public class CameraBehaviour : MonoBehaviour
     private Vector3 _initPosition; //平移时用于存储平移的起点位置
     private Vector3 _cameraX; //相机的x轴方向向量
     private Vector3 _cameraY; //相机的y轴方向向量
-    private Vector3 _cameraZ; //相机的z轴方向向量
-
     private Vector3 _initScreenPosition; //中键刚按下时鼠标的屏幕坐标（第三个值其实没什么用）
     private Vector3 _cursorScreenPosition; //当前鼠标的屏幕坐标（第三个值其实没什么用）
 
+    private Camera _mainCamera;
+
     private void Start()
     {
         //这里就是设置一下初始的相机视角以及一些其他变量，这里的x和y。。。是和下面getAxis的mouse x与mouse y对应
@@ -36,13 +35,16 @@ private void Start()
         _eulerY = angles.x;
         _targetPosition = target.position;
         _cameraRotation = Quaternion.Euler(_eulerY + 60, _eulerX, 0);
+        
         // 引入中间变量 提高代码效率
         var transform1 = transform;
-        transform1.rotation = _cameraRotation; //设置相机姿态
-        /*var position =
-            _cameraRotation * new Vector3(0.0F, 0.0F, -_distance) +
-            _targetPosition; //四元数表示一个旋转，四元数乘以向量相当于把向量旋转对应角度，然后加上目标物体的位置就是相机位置了*/
-        transform1.position = _cameraRotation * new Vector3(0, 0, -_distance) + _targetPosition; //设置相机位置
+        //设置相机姿态
+        transform1.rotation = _cameraRotation;
+        //设置相机位置
+        transform1.position = _cameraRotation * new Vector3(0, 0, -_distance) + _targetPosition;
+        
+        // 获得主摄像机
+        _mainCamera = Camera.main;
     }
 
     private void Update()
@@ -65,7 +67,7 @@ private void Update()
         }
         else if (Input.GetAxis("Mouse ScrollWheel") != 0) //鼠标滚轮缩放功能
         {
-            if (_distance >= MouseZoomMin && _distance <= MouseZoomMax)
+            if (_distance is >= MouseZoomMin and <= MouseZoomMax)
             {
                 _distance -= Input.GetAxis("Mouse ScrollWheel") * MouseWheelSensitivity;
             }
@@ -91,12 +93,11 @@ private void Update()
             var transform1 = transform;
             _cameraX = transform1.right;
             _cameraY = transform1.up;
-            _cameraZ = transform1.forward;
 
             _initScreenPosition = new Vector3(Input.mousePosition.x, Input.mousePosition.y, _targetOnScreenPosition.z);
 
             //targetOnScreenPosition.z为目标物体到相机平面的法线距离
-            _targetOnScreenPosition = Camera.main!.WorldToScreenPoint(_targetPosition);
+            _targetOnScreenPosition = _mainCamera.WorldToScreenPoint(_targetPosition);
             _initPosition = _targetPosition;
         }
 
@@ -117,7 +118,6 @@ private void Update()
 
         if (Input.GetMouseButtonUp(2))
         {
-            Debug.Log("upOnce");
             //平移结束把cameraTargetPosition的位置更新一下，不然会影响缩放与旋转功能
             _targetPosition = target.position;
         }