1.2D实现两物体的自动对准效果
在捕鱼游戏中，玩家的手指点击屏幕，炮弹自动打向手指的方向是怎样实现的？
首先来想一下，如果我们想要自动追踪玩家手指的运动我们需要知道，手指按下的位置与炮弹的位置相差的角度，那么这个角度要怎样计算呢？
首先，我们尝试着把手指与炮管放在同一个坐标系中，如下图
所以我们现在要算出来的应该是那个坐标呢？其实不管是算角x0玩家（角1）或者角玩家0x（角2）也好，算出其中一个然后用90-这个角度就可以了，我们现在以角1来举例，，这个角的角度tan角度 = （敌人坐标Y-玩家坐标Y）/（敌人坐标x-玩家坐标x） ，这样球出来的是一个tan数值，所以我们需要把这个角度转换成我们熟知的度数，也就是 float angle = Mathf.Atan(tan角度)，求出了选装的角度，就可以来设置物体自身欧拉角，由于我们要选装的事XY轴构成的平面，我们要以z轴为旋转轴来选装，使物体绕着自身的坐标系旋转求出的角度，这样敌人就可以根据玩家的位置自动瞄准了，代码如下
using UnityEngine;using System.Collections;public class enemy : MonoBehaviour {//存储角度值。private float angle;//玩家位置。public Transform m_player;//申请一个变量存储gun游戏物体的prefab。public Transform gun;void Start () {}void Update () {//计算角度angle =Mathf.Rad2Deg*Mathf.Atan ((transform.position.y - m_player.position.y) / (transform.position.x - m_player.position.x));//判断角度所在象限，并进行修正。if (transform.position.x - m_player.position.x < 0)angle=angle-90;else angle=angle+90;//设置物体的自身欧拉角，是物体绕自身坐标系在Z轴，旋转Z度。transform.localEulerAngles=new Vector3(0,0,angle);//生成gun物体。Instantiate (gun, transform.position, transform.rotation);}}
2.实现钟摆的往复运动
方法一：使用unity自带的链节组件，进行相应的设置之后可以实现
这里要说的是第二种方法，也就是代码实现
在这里实际上是通过计算旋转轴、通过角速度旋转、然后通过transform.RotateAround来实现围绕某一个轴旋转角度的效果
using UnityEngine;using System.Collections;public class Pendulum : MonoBehaviour{public Transform m_anchor; //圆点public float g = 9.8f; //重力加速度private Vector3 m_rotateAxis; //旋转轴private float w = 0;//角速度// Use this for initializationvoid Start(){//求出旋转轴m_rotateAxis = Vector3.Cross(transform.position - m_anchor.position, Vector3.down);}void DoPhysics(){float r = Vector3.Distance(m_anchor.position, transform.position);float l = Vector3.Distance(new Vector3(m_anchor.position.x, transform.position.y, m_anchor.position.z), transform.position);//当钟摆摆动到另外一侧时，l为负，则角加速度alpha为负。Vector3 axis = Vector3.Cross(transform.position - m_anchor.position, Vector3.down);if (Vector3.Dot(axis, m_rotateAxis) < 0){l = -l;}float cosalpha = l / r;//求角加速度float alpha = (cosalpha * g) / r;//累计角速度w += alpha * Time.deltaTime;//求角位移(乘以180/PI 是为了将弧度转换为角度)float thelta = w * Time.deltaTime * 180.0f / Mathf.PI/2;//绕圆点m_ahchor的旋转轴m_rotateAxis旋转thelta角度transform.RotateAround(m_anchor.position, m_rotateAxis, thelta);}// Update is called once per framevoid Update(){DoPhysics();}}
第二种方法
using System.Collections;using System.Collections.Generic;using UnityEngine;public class moveText : MonoBehaviour{public Transform cur;bool forward = false;// Start is called before the first frame updatevoid Start(){}// Update is called once per framevoid Update(){float angle = (cur.transform.position.y - this.transform.position.y) / (cur.transform.position.x - this.transform.position.x);angle = Mathf.Rad2Deg* Mathf.Atan(angle);move_back(move_dir(this.transform.position.x));move_forward(forward);}private bool move_dir(float pos){if (pos < -12){forward = true;Debug.Log(this.transform.position.x);}if (pos > 6){forward = false;}return forward;}private void move_forward(bool fob){if(!fob){this.transform.RotateAround(cur.transform.position, Vector3.back, 10*Time.deltaTime);}return;}public void move_back(bool fob){if(fob){this.transform.RotateAround(cur.transform.position, Vector3.forward , 10*Time.deltaTime);}return;}}
弧形运动移动到指定地点
using UnityEngine;using System.Collections;public class MoveTest : MonoBehaviour{public GameObject target; //要到达的目标 public float speed = 10; //速度 public int rotationAngle = 60;private float distanceToTarget; //两者之间的距离 private bool move = true;public GameObject target2;void Start(){//计算两者之间的距离 distanceToTarget = Vector3.Distance(this.transform.position, target.transform.position);StartCoroutine(Move());}IEnumerator Move(){while (move) //移动到目标点停止移动{Vector3 targetPos = target.transform.position;//让始终它朝着目标 this.transform.LookAt(targetPos);//计算弧线中的夹角 float angle = Mathf.Min(1, Vector3.Distance(this.transform.position, targetPos) / distanceToTarget) * rotationAngle;this.transform.rotation = this.transform.rotation * Quaternion.Euler(Mathf.Clamp(-angle, -42, 42), 0, 0);float currentDist = Vector3.Distance(this.transform.position, target.transform.position);if (currentDist < 0.5f)move = true;this.transform.Translate(Vector3.forward * Mathf.Min(speed * Time.deltaTime, currentDist));yield return null;}while(!move){Vector3 targetPos = target2.transform.position;//让始终它朝着目标 this.transform.LookAt(targetPos);//计算弧线中的夹角 float angle = Mathf.Min(1, Vector3.Distance(this.transform.position, targetPos) / distanceToTarget) * rotationAngle;this.transform.rotation = this.transform.rotation * Quaternion.Euler(Mathf.Clamp(-angle, -42, 42), 0, 0);float currentDist = Vector3.Distance(this.transform.position, target.transform.position);if (currentDist < 0.5f)move = false;this.transform.Translate(Vector3.forward * Mathf.Min(speed * Time.deltaTime, currentDist));yield return null;}}}
