HomeDesign/Assets/CirclePoint.cs

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

public class CirclePoint : MonoBehaviour {
    private Image img;
    private bool interact;
    public Sprite Spr1;
    public Sprite Spr2;
	// Use this for initialization
	void Start () {
        img = GetComponent<Image>();
	}
	
	// Update is called once per frame
	void Update () {
        ChangeSprite();
        CirclePoint1();
    }

    void ChangeSprite()
    {
        Ray ray = Camera.main.ScreenPointToRay(new Vector3(Screen.width / 2, Screen.height / 2, 0));
        RaycastHit hit;
        if (Physics.Raycast(ray, out hit))
        {
            if (hit.collider.tag == "cube" || hit.collider.tag == "floor") //判断碰撞物体的tag,这里是表示可以被交互的物体
            {
                interact = true;
            }
            else   //不可以被交互的物体
            {
                interact = false;
            }

        }
        else  //没有碰撞体的物体
        {
            interact = false;
        }
    }

    void CirclePoint1()  //准心的放大与缩小动画
    {
        if (interact)
        {
            img.sprite = Spr2;

        }
        else { img.sprite = Spr1;
           
        } //准心不显示   
    }
}