Unity3D --//通过射线判断角色是否在地面

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

public class PlayerContro : MonoBehaviour {

    public float speed;
    public Animator myAnimator;
    public SpriteRenderer spriteRenderer;
    // Use this for initialization
    private bool isGround = false;
    private Rigidbody2D myRigidbody2D;
    void Start () {
        myAnimator = GetComponent<Animator>();
        myRigidbody2D = GetComponent<Rigidbody2D>();
    }
	
	// Update is called once per frame
	void Update () {
        float x = Input.GetAxis("Horizontal");

        //旋转逻辑
        if (x >0)
        {
            spriteRenderer.flipX = false;
        }
        else if(x < 0)
        {
            spriteRenderer.flipX = true;
        }

        //角色是否在地面
        Debug.DrawRay(transform.position, Vector2.down * 0.11f, Color.red);
        RaycastHit2D hit = Physics2D.Raycast(transform.position, Vector2.down, 0.15f, 1 << 8);
        if (hit.collider != null)
        {
            isGround = true;
        }
        else
        {
            isGround = false;
        }

        //角色状态
        if (!isGround)//角色没有与地面接触
        {
            //  myAnimator.SetInteger("player_state", 2);
            myAnimator.Play("jump");
        }
        else //校色与地面接触
        {
             if (x == 0)
            {
                //    myAnimator.SetInteger("player_state", 0);
                myAnimator.Play("idle");
            }
            else
            {
                //   myAnimator.SetInteger("player_state", 1);
                myAnimator.Play("run");

            }
        }
       

        //角色行为控制
        transform.Translate(Vector3.right*x*Time.deltaTime*speed);
        // myRigidbody2D.velocity = Vector2.right * x * speed;
        // myRigidbody2D.MovePosition(Vector2.right*x*Time.deltaTime*speed);

        // myRigidbody2D.MovePosition(myRigidbody2D.position + Vector2.right * speed * Time.deltaTime * x);
        // Vector2 vector2 = new Vector2(1, 0.0f) * speed * x;
        // myRigidbody2D.velocity = vector2;
      
        if (Input.GetKeyDown("space"))
        {
            if (isGround)
            {
                myRigidbody2D.AddForce(Vector2.up * 180);
            }
          
        }
    }

}