[Unity3D] 视角旋转学习笔记_unity 相机环绕

目录

前言

一、基础旋转

1.1  相机环绕角色旋转

Declaration

Description

1.2  LookAt()函数

二、通过鼠标拖拽距离来旋转视角

前言

学习笔记，仅供学习，不做商用，如有侵权，联系我删除即可。

参考博文：

Unity 自由视角的惯性旋转https://haiyue.blog.csdn.net/article/details/123297435

一、基础旋转

1.1  相机环绕角色旋转

使用Transform.RotateAround，axis为轴，方向旋转

Declaration

public void RotateAround(Vector3 point, Vector3 axis, float angle);

Description

Rotates the transform about axis passing through point in world coordinates by angle degrees.

This modifies both the position and the rotation of the transform.

using UnityEngine;
 
//Attach this script to a GameObject to rotate around the target position.
public class Example : MonoBehaviour
{
    //Assign a GameObject in the Inspector to rotate around
    public GameObject target;
 
    void Update()
    {
        // Spin the object around the target at 20 degrees/second.
        transform.RotateAround(target.transform.position, Vector3.up, 20 * Time.deltaTime);
    }
}

1.2  LookAt()函数

根据官方的文档描述，该函数的功能是，旋转自身，使得当前对象的正z轴指向目标对象target所在的位置。

而对于worldUp的描述是，在完成上面的旋转之后，继续旋转自身，使得当前对象的正y轴朝向与worldUp所指向的朝向一致.

可以使用LookAt函数修正，让相机正确地朝向角色

二、通过鼠标拖拽距离来旋转视角

按下鼠标右键时，每一帧都获取鼠标的位置，通过两帧之间的鼠标位置之差，即可求得两帧之间的鼠标速度。

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
 
public class PlayerTransform : MonoBehaviour
{
    public Transform HeadTransform;
    private float CamDepthSmooth = 200f;
    private Vector3 RelativePos;
 
    // Start is called before the first frame update
    void Start()
    {
        RelativePos = transform.position - HeadTransform.position;
    }
 
    // Update is called once per frame
    void Update()
    {
        transform.position = HeadTransform.position + RelativePos;
        DragToRotateView_Distance();
        // 视角的拉近和放远
        if ((Input.mouseScrollDelta.y < 0 && Camera.main.fieldOfView >= 3) ||
            (Input.mouseScrollDelta.y > 0) && Camera.main.fieldOfView <= 80)
        {
            Camera.main.fieldOfView += Input.mouseScrollDelta.y * CamDepthSmooth * Time.deltaTime;
        }
    }
 
    /*            通过鼠标拖拽距离来旋转视角            */
    Vector3 Point1;
    Vector3 Point2;
    // 旋转每度在一帧中需要拖拽的距离
    int DragDistancePerAngle = 8;
    void DragToRotateView_Distance()
    {
        
        if (Input.GetMouseButtonDown(1))          // 按下右键的瞬间记录起始位置
        {
            Point1 = Input.mousePosition;
            //StartPoint = Point1;
        }
 
        if (Input.GetMouseButton(1))              // 按下右键每一帧都执行
        {
            Point2 = Input.mousePosition;
            float dx = Point2.x - Point1.x;
            float dy = Point2.y - Point1.y;
 
            float AngleX = dx / DragDistancePerAngle;
            float AngleY = dy / DragDistancePerAngle;
 
            transform.RotateAround(HeadTransform.position, Vector3.up, AngleX);
            transform.RotateAround(HeadTransform.position, -transform.right, AngleY);
            transform.LookAt(HeadTransform);
 
            RelativePos = transform.position - HeadTransform.position;
 
            Point1 = Point2;
            Point2 = Vector3.zero;
        }
    }
}