使用鼠标拖动为相机创建边界

Posted 2023-04-12

【中文标题】使用鼠标拖动为相机创建边界

【英文标题】：Creating boundaries for Camera with with mouse drag

【发布时间】：2022-01-20 14:31:12

【问题描述】：

我制作了一个通过拖动鼠标移动的正交相机，但不知道如何为其创建边界。看来我必须使用 Mathf.Clamp 但不知道如何使用。

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class CamController : MonoBehaviour

    public Transform cameraTransform;

    public float movementSpeed;
    public float movementTime;

    public Vector3 newPosition;

    public Vector3 dragStartPosition;
    public Vector3 dragCurrentPosition;

    public Camera cam;
    public float maxZoom = 5;
    public float minZoom = 20;
    public float sensitivity = 1;
    public float speed = 30;
    float targetZoom;

    public float minX = 100;
    public float maxX = 120;
    
    // Start is called before the first frame update
    void Start()
    
        newPosition = transform.position;
    

    // Update is called once per frame
    void Update()
    
        HandleMouseInput();
        HandleMovementInput();

        
            targetZoom -= Input.mouseScrollDelta.y * sensitivity;
            targetZoom = Mathf.Clamp(targetZoom, maxZoom, minZoom);
            float newSize = Mathf.MoveTowards(cam.orthographicSize, targetZoom, speed * Time.deltaTime);
            cam.orthographicSize = newSize;
        
    

    void HandleMouseInput()
    
        if (Input.GetMouseButtonDown(0))
        
            Plane plane = new Plane(Vector3.up, Vector3.zero);

            Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);

            float entry;

            if (plane.Raycast(ray, out entry))
            
                dragStartPosition = ray.GetPoint(entry);
            
        

        if (Input.GetMouseButton(0))
        
            Plane plane = new Plane(Vector3.up, Vector3.zero);

            Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);

            float entry;

            if (plane.Raycast(ray, out entry))
            
                dragCurrentPosition = ray.GetPoint(entry);

                newPosition = transform.position + dragStartPosition - dragCurrentPosition;
            
        

        newPosition = Mathf.Clamp(minX, minX);
    

    void HandleMovementInput()
    
        if (Input.GetKey(KeyCode.D) || Input.GetKey(KeyCode.RightArrow))
        
            newPosition += (transform.forward * movementSpeed);
        

        if (Input.GetKey(KeyCode.A) || Input.GetKey(KeyCode.LeftArrow))
        
            newPosition += (transform.forward * -movementSpeed);
        

        if (Input.GetKey(KeyCode.S) || Input.GetKey(KeyCode.DownArrow))
        
            newPosition += (transform.right * movementSpeed);
        

        if (Input.GetKey(KeyCode.W) || Input.GetKey(KeyCode.UpArrow))
        
            newPosition += (transform.right * -movementSpeed);
        

        transform.position = Vector3.Lerp(transform.position, newPosition, Time.deltaTime * movementTime);
    

【问题讨论】：

您共享了很多代码，但有什么方法可以将其简化为minimal reproducible example？问题到底出在哪里——是在Update() 中吗？如果是这样，您当前的实施做错了什么？您分享的当前卡在哪里的越多，我们就越有可能帮助您解决问题。请参阅：How to Ask。

感谢您的回复。问题在于无效的 HandleMouseInput。我用过 newPosition = Mathf.Clamp(minX, minX);创建了两个浮动公共浮动 minX 和 max。鼠标拖动停止工作

【参考方案1】：

newPosition = Mathf.Clamp(minX, minX);

你不能只用两个参数来钳位..你需要一个电流、一个最小值和一个最大值..你不能只是将float 转换为Mathf.Clamp 返回的Vector3 （3 个浮点数）

我认为你的意思有点像例如

newPosition.x = Mathf.Clamp(newPosition.x, minX, maxX);

但是，在 HandleMovementInput 之后，您仍然会覆盖它，因此您可能希望更改夹紧的时刻，而是在应用新位置之前立即执行。