求教！跳跃代码报错

[Ian Tsai]

求助！
原案例是基于Unity4的，我用的是Unity5
#70和#89行报错，原因是jumpMaterial没有定义。说实话这段代码我理解不了为什么要这样设计，求高人指点

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

public class PlayController : MonoBehaviour {
    [HideInInspector]
    public bool isFacingRight = true;
    [HideInInspector]
    public bool isJumping = false;
	[HideInInspector]
	public bool isDoubleJumping = false;
    [HideInInspector]
    public bool isGrounded = false;

    public float jumpForce = 650.0f;
    public float maxSpeed = 7.0f;

    public Transform groundCheck;
    public LayerMask groundLayers;

    private float groundCheckRadius = 0.2f;
	private Animator anim;

	void awake(){
		anim = GetComponent<Animator> ();
	}
//	// Use this for initialization
//	void Start () {
//	}
	
	// Update is called once per frame
	void Update () {
		if (Input.GetButtonDown ("Jump")) 
		{
			if (isGrounded == true) {
				this.GetComponent<Rigidbody2D> ().velocity = new Vector2 (GetComponent<Rigidbody2D> ().velocity.x, 0);
				this.GetComponent<Rigidbody2D> ().AddForce (new Vector2 (0, jumpForce));
				this.anim.SetTrigger ("Jump");
			} else if (isDoubleJumping == false) {
				isDoubleJumping = true;
				this.GetComponent<Rigidbody2D> ().velocity = new Vector2 (GetComponent<Rigidbody2D> ().velocity.x, 0);
				this.GetComponent<Rigidbody2D> ().AddForce (new Vector2 (0, jumpForce));
			}


		}
	}

    private void FixedUpdate()
    {
		isGrounded = Physics2D.OverlapCircle
			(groundCheck.position, groundCheckRadius, groundLayers);
	
		PhysicsMaterial2D material = this.gameObject.GetComponent<CircleCollider2D> ().sharedMaterial;

		if(isGrounded==true)
		{
			isDoubleJumping=false;
		}
		if (isGrounded == true && material == this.jumpMaterial) {
			CircleCollider2D collision = this.gameObject.GetComponent<CircleCollider2D> ();
			collision.sharedMaterial = null;
			collision.enabled = false;
			collision.enabled = true;
		}
		else if(isGrounded ==false&&this.gameObject.GetComponent<CircleCollider2D>().sharedMaterial==null)
			{
				CircleCollider2D collision = this.gameObject.GetComponent<CircleCollider2D> ();
				collision.sharedMaterial = this.jumpMaterial;
				collision.enabled = false;
				collision.enabled = true;
			}
			

		float move = Input.GetAxis ("Horizontal");
		try
		{
			this.GetComponent<Rigidbody2D>().velocity = new Vector2 (move * maxSpeed, GetComponent<Rigidbody2D>().velocity.y);
			this.anim.SetFloat("Speed",Mathf.Abs(move));
			if ((move > 0.0f && isFacingRight == false)|| (move < 0.0f && isFacingRight == true)) 
			{
				Flip ();
			}
		}
		catch(UnityException error){
			Debug.LogError (error.toString ());
		}
	}
	void Flip()
	{
		isFacingRight = !isFacingRight;
		Vector3 playerScale = transform.localScale;
		playerScale.x = playerScale.x * -1;
		transform.localScale = playerScale;
	}
}

[带酒书生]

你就没定义jumpmaterial，肯定报错啊