相机跟随 - 考虑将值存储在临时变量中答案

【问题标题】：Camera Follow - Consider storing the value in a temporary variable相机跟随 - 考虑将值存储在临时变量中
【发布时间】：2015-09-11 01:12:35
【问题描述】：

无法让这条线正常工作，它需要一个临时变量。没有它，相机会平放在地面上

transform.position.y = currentHeight;

错误 CS1612：无法修改“UnityEngine.Transform.position”的值类型返回值。考虑将值存储在临时变量中

部分代码不是我的，只是试图从java脚本转换为c-sharp并在我当前的相机脚本中实现

 // Calculate the current rotation angles
 var wantedRotationAngle = target.eulerAngles.y;
 var wantedHeight = target.position.y + height;
 var currentRotationAngle = transform.eulerAngles.y;
 var currentHeight = transform.position.y;
 // Damp the rotation around the y-axis
 currentRotationAngle = Mathf.LerpAngle (currentRotationAngle, wantedRotationAngle, rotationDamping * Time.deltaTime);
 // Damp the height

 currentHeight = Mathf.Lerp (currentHeight, wantedHeight, heightDamping * Time.deltaTime);
 // Convert the angle into a rotation

 var currentRotation = Quaternion.Euler (0, currentRotationAngle, 0);
 // Set the position of the camera on the x-z plane to:
 // distance meters behind the target
 transform.position = target.position;
 transform.position -= currentRotation * Vector3.forward * distance;
 // Set the height of the camera

 transform.position.y = currentHeight;

 // Always look at the target
 transform.LookAt (target);

【问题讨论】：

标签： c# unity3d

【解决方案1】：

我不相信您可以像那样设置矢量的单独轴，您可以这样做的一种方法是

// Calculate the current rotation angles
var wantedRotationAngle = target.eulerAngles.y;
var wantedHeight = target.position.y + height;
var currentRotationAngle = transform.eulerAngles.y;
var currentHeight = transform.position.y;
// Damp the rotation around the y-axis
currentRotationAngle = Mathf.LerpAngle (currentRotationAngle, wantedRotationAngle, rotationDamping * Time.deltaTime);
// Damp the height

currentHeight = Mathf.Lerp (currentHeight, wantedHeight, heightDamping * Time.deltaTime);
// Convert the angle into a rotation

var currentRotation = Quaternion.Euler (0, currentRotationAngle, 0);
// Set the position of the camera on the x-z plane to:
// distance meters behind the target
transform.position = target.position;
transform.position -= currentRotation * Vector3.forward * distance;
// Set the height of the camera

Vector3 temp = transform.position; //Get the current vector the transform is at
temp.y = currentHeight; //assign the new value to the Y axis
transform.position = temp; //replace the existing vector with the new one we just modified.

// Always look at the target
transform.LookAt (target);

所以我们将您的transform.position.y = currentHeight; 行替换为

Vector3 temp = transform.position; //Get the current vector the transform is at
temp.y = currentHeight; //assign the new value to the Y axis
transform.position = temp; //replace the existing vector with the new one we just modified.

这仅仅是因为我相信 C# 处理结构和属性的方式。

【讨论】：

这肯定会导致同样的问题吗？那个y不能修改？我认为它需要分配一个新对象：transform.position = new Vector3(transform.position.x, currentHeight, transform.position.z);
我已经有一段时间没有使用统一了，但我相信这确实有效。需要@Alex_TNT 确认。
酷，我想我会检查 :)
这种混淆是因为Vector3 是一个可变结构。 transform.position 获取结构的副本，因此您必须获取副本，对其进行操作，然后再次设置 transform.position。 Unity 这样做是出于性能原因，尽管它可能会非常令人困惑。

【解决方案2】：

您不能直接修改 transform.position x 和 y，您应该创建一个具有所需值的 Vector3 变量，然后将您的 transform.position 分配给它。例如：

 Vector3 newPosition = new Vector3(0, currentHeight, 0);
 transform.position = newPosition;

【讨论】：