unity3d可调初速度的平抛运动

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

public class HorizontalProjectileMotion : MonoBehaviour {
public float time=3;//代表从A点出发到B经过的时长
public Transform pointA;//点A
public Transform pointB;//点B
public float g=-10;//重力加速度
// Use this for initialization
private Vector3 speed;//初速度向量
public float mySpeed=10;
private Vector3 Gravity;//重力向量
private bool ismove;
void Start () {
time =(pointB.position.x - pointA.position.x)/mySpeed;
Debug.Log(time);
transform.position = pointA.position;//将物体置于A点
//通过一个式子计算初速度
speed = new Vector3((pointB.position.x - pointA.position.x)/time,
(pointB.position.y-pointA.position.y)/time-0.5fgtime, (pointB.position.z - pointA.position.z) / time);
Gravity = Vector3.zero;//重力初始速度为0
}
private float dTime=0;
// Update is called once per frame
void FixedUpdate () {

    if(ismove)
    {
    Gravity.y = g * (dTime += Time.fixedDeltaTime);//v=at
    //模拟位移
    transform.Translate(speed*Time.fixedDeltaTime);
    transform.Translate(Gravity * Time.fixedDeltaTime);
    }
    if(transform.position.x>=pointB.transform.position.x)
    {
        transform.position=pointB.position;
        pointA.position=pointB.position;
        pointB.position=new Vector3(pointB.position.x+Random.Range(0,10),pointB.position.y+Random.Range(-5,5),0);
        ismove=false;
    }
}

public void Jump()
{
    time =(pointB.position.x - pointA.position.x)/mySpeed;
    Debug.Log(time);
    transform.position = pointA.position;//将物体置于A点
    //通过一个式子计算初速度
    speed = new Vector3((pointB.position.x - pointA.position.x)/time,
        (pointB.position.y-pointA.position.y)/time-0.5f*g*time, (pointB.position.z - pointA.position.z) / time);
    Gravity = Vector3.zero;//重力初始速度为0
    dTime=0;
    ismove=true;
}

}