如何使相机跟随unity3d C#中的对象？

Question

我有一个名为 Ball 的对象，我向它添加了键盘交互性（WASD 移动球） 我需要摄像头留在后面跟随球，但我遇到了错误。

using UnityEngine;
using System.Collections;
public class ballmain : MonoBehaviour {
    public bool isMoving = false;
    public string direction;
    public float camX;
    public float camY;
    public float camZ;
    // Use this for initialization
    void Start () {
        Debug.Log("Can this run!!!");
    }

    // Update is called once per frame
    void Update () {
        camX = rigidbody.transform.position.x -=10;
        camY = rigidbody.transform.position.y -=10;
        camZ = rigidbody.transform.position.z;
        camera.transform.position = new Vector3(camX, camY, camZ);
            //followed by code that makes ball move
    }
}

我收到错误“Assets/ballmain.cs(18,44): error CS1612: Cannot modify a value type return value of 'UnityEngine.Transform.position'。考虑将值存储在临时变量中” 有人知道答案吗？如果我注释掉有关相机的代码，球可以四处移动。

Answer 1

给你。完整的代码。

简单跟随

using UnityEngine;
using System.Collections;

public class Follow: MonoBehaviour {
public Transform target;
public float smooth= 5.0f;
void  Update (){
    transform.position = Vector3.Lerp (
        transform.position, target.position,
        Time.deltaTime * smooth);
} 

    } 

高级关注

using UnityEngine;
using System.Collections;

public class SmoothFollowScript: MonoBehaviour {

// The target we are following
public  Transform target;
// The distance in the x-z plane to the target
public int distance = 10.0;
// the height we want the camera to be above the target
public int height = 10.0;
// How much we 
public heightDamping = 2.0;
public rotationDamping = 0.6;


void  LateUpdate (){
    // Early out if we don't have a target
    if (TargetScript.russ == true){
    if (!target)
        return;

    // Calculate the current rotation angles
    wantedRotationAngle = target.eulerAngles.y;
    wantedHeight = target.position.y + height;

    currentRotationAngle = transform.eulerAngles.y;
    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
    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);
}
}
}

Answer 2

如果您只是想跟随目标对象，请按照您想要的方式对齐相机的位置，并使相机成为目标对象的子对象，其余的就可以了

Answer 3

这是我在游戏开发过程中发现的一个有用的脚本。我没有创建它们，所以我感谢 wiki.unity3d.com 提供了这个惊人的脚本。

流畅跟随：

using UnityEngine;
using System.Collections;

        public class SmoothFollow2 : MonoBehaviour {
        public Transform target;
        public float distance = 3.0f;
        public float height = 3.0f;
        public float damping = 5.0f;
        public bool smoothRotation = true;
        public bool followBehind = true;
        public float rotationDamping = 10.0f;

        void Update () {
               Vector3 wantedPosition;
               if(followBehind)
                       wantedPosition = target.TransformPoint(0, height, -distance);
               else
                       wantedPosition = target.TransformPoint(0, height, distance);

               transform.position = Vector3.Lerp (transform.position, wantedPosition, Time.deltaTime * damping);

               if (smoothRotation) {
                       Quaternion wantedRotation = Quaternion.LookRotation(target.position - transform.position, target.up);
                       transform.rotation = Quaternion.Slerp (transform.rotation, wantedRotation, Time.deltaTime * rotationDamping);
               }
               else transform.LookAt (target, target.up);
         }
}

More information about my work

Answer 4

将标准移动资产添加到您的项目中。它的脚本部分包含一个 SmoothFollow2D.js 代码。将此代码与游戏对象附加并初始化公共变量。这将为您完成这项工作。

Answer 5

我发现了这个简单实用的统一 2d 相机跟随脚本。

using UnityEngine;
using System.Collections;

public class FollowCamera : MonoBehaviour {

public float interpVelocity;
public float minDistance;
public float followDistance;
public GameObject target;
public Vector3 offset;
Vector3 targetPos;
// Use this for initialization
void Start () {
    targetPos = transform.position;
}

// Update is called once per frame
void FixedUpdate () {
    if (target)
    {
        Vector3 posNoZ = transform.position;
        posNoZ.z = target.transform.position.z;

        Vector3 targetDirection = (target.transform.position - posNoZ);

        interpVelocity = targetDirection.magnitude * 5f;

        targetPos = transform.position + (targetDirection.normalized * interpVelocity * Time.deltaTime); 

        transform.position = Vector3.Lerp( transform.position, targetPos + offset, 0.25f);

    }
   }
}

来源unity2d camera follow script

Answer 6

这些行中的-=：

   camX = rigidbody.transform.position.x -=10;
   camY = rigidbody.transform.position.y -=10;

错了。 -= 将尝试修改 rigidbody.transform.position。你只想要-。

但是，就目前而言，相机不会跟踪目标 Z 位置的变化，如果相机旋转，它也不会正确跟踪。要获得您需要的正确位置（在向量中）：-

cam_pos = target_pos - dist_to_target * cam_look_at