ufo/Assets/Script/PlayerControl.cs

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

public class PlayerControl : MonoBehaviour
{
    public float minSpeed = 0.7f;
    public float maxSpeed = 1.4f;

    private float dis = 0;
    private float player_speed = 0;

    // Use this for initialization
    void Start()
    {

    }

    // Update is called once per frame
    void Update()
    {
        Vector3 mousePos = Camera.main.ScreenToWorldPoint(Input.mousePosition);
        mousePos.z = 0;

        dis = Vector2.Distance(new Vector2(transform.position.x, transform.position.y), new Vector2(mousePos.x, mousePos.y));
        if (dis <= 0.1f)
        {

        }
        else
        {
            TurnTo(mousePos);

            player_speed = dis * 0.5f;
            player_speed = Mathf.Clamp(player_speed, minSpeed, maxSpeed);
            transform.Translate(Vector3.up * Time.deltaTime * player_speed);
        }
    }

    void TurnTo(Vector3 pos)
    {
        Vector3 dir = pos - transform.position;
        float theta = Mathf.Atan2(dir.y, dir.x);
        float angle = theta * Mathf.Rad2Deg;
        transform.localEulerAngles = new Vector3(0, 0, angle - 90);

    }

    void OnTriggerEnter2D(Collider2D other)
    {
        Destroy(other.gameObject);
    }




}