unity实现车方向盘转动效果

本文实例为大家分享了unity实现车方向盘转动效果的具体代码，供大家参考，具体内容如下

效果：

c#脚本如下：

using system;
using system.collections;
using system.collections.generic;
using unityengine;
using unityengine.eventsystems;

public class newbehaviourscript : monobehaviour, idraghandler,ibegindraghandler,ienddraghandler
{
  /// <summary>
  /// 需要旋转的模型
  /// </summary>
  public transform model;
  /// <summary>
  /// 父物体的recttransform
  /// </summary>
  public recttransform parentrect;
  /// <summary>
  /// 旋转的ui
  /// </summary>
  public recttransform img;
  /// <summary>
  /// 摄像机
  /// </summary>
  public camera cam;
  /// <summary>
  /// 是否在拖拽
  /// </summary>
  private bool drag = false;
  /// <summary>
  /// 初始角度
  /// </summary>
  private float originangle = 0;
  /// <summary>
  /// 自身角度
  /// </summary>
  private float selfangle1 = 0;
  /// <summary>
  /// 上一次和当前的角度
  /// </summary>
  private float lastangle = 0f;
  private float currentangle = 0f;
  /// <summary>
  /// 上一次和当前的位置
  /// </summary>
  private vector2 currentpos;
  private vector2 lastpos;

  public void onbegindrag(pointereventdata eventdata)
  {
    drag = true;

    originangle = getangle(eventdata.position);

    selfangle1 = (img.transform as recttransform).eulerangles.z;
  }

  public void ondrag(pointereventdata eventdata)
  {
    if (drag)
    {
      lastangle = currentangle;
      currentangle = getangle(eventdata.position);

      float val = touchjudge(currentpos, ref lastpos, vector2.zero);
      if (val > 0f && val <180f)
      {
        img.eulerangles = new vector3(0f,0f, -currentangle + originangle + selfangle1);
        model.eulerangles = new vector3(0f, 0f, -currentangle + originangle + selfangle1);
      }
    }
  }

  public void onenddrag(pointereventdata eventdata)
  {
    drag = false;
  }
  /// <summary>
  /// 将屏幕坐标转成ui坐标
  /// </summary>
  /// <param name="pos1"></param>
  /// <returns></returns>
  float getangle(vector2 pos1) {
    vector2 pos;
    recttransformutility.screenpointtolocalpointinrectangle(parentrect, pos1, cam, out pos);
    currentpos = pos;
    return mathf.atan2(pos.x, pos.y) * mathf.rad2deg;
  }
  /// <summary>
  /// 判断顺时针还是逆时针旋转
  /// </summary>
  /// <param name="current"></param>
  /// <param name="last"></param>
  /// <param name="anchor"></param>
  /// <returns></returns>
  private float touchjudge(vector2 current, ref vector2 last, vector2 anchor)
  {
    vector2 lastdir = (last - anchor).normalized; 
    vector2 currentdir = (current - anchor).normalized;

    float lastdot = vector2.dot(vector2.right, lastdir);
    float currentdot = vector2.dot(vector2.right, currentdir);

    float lastangle = last.y < anchor.y
       ? mathf.acos(lastdot) * mathf.rad2deg
       : -mathf.acos(lastdot) * mathf.rad2deg;

    float currentangle = current.y < anchor.y
      ? mathf.acos(currentdot) * mathf.rad2deg
      : -mathf.acos(currentdot) * mathf.rad2deg;

    last = current;
    return currentangle - lastangle;
  }
}

canvas设置如下：

脚本赋值如下：

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。