AddForce给物体添加刚体效果并且脚本增加一个力（按空格实现）

using UnityEngine;
using System.Collections;

public class CubeAddForce : MonoBehaviour {

    float hor,ver;
    //力的方向向量
    Vector3 forceDir;
    //力的大小
    public float force = ;

    Rigidbody rig;

    void Start()
    {
        rig = GetComponent<Rigidbody> ();
    }

    void Update()
    {
        hor = Input.GetAxis ("Horizontal");
        ver = Input.GetAxis ("Vertical");

        forceDir = new Vector3 (hor,,ver);
        //施加一个力
        rig.AddForce (forceDir * force);
        if (Input.GetKeyDown (KeyCode.Space)) {
            rig.AddExplosionForce (, Vector3.zero, );
        }
    }

}