Unity3D - 为什么我的对象不会每秒移动每一帧

Question

Im struggling with very weird and propably simple problem,I have created a robot and his task is to move towards target I mean Im using Vector3.MoveTowards function in void update to move my robot per every frame but the problem is that he is moving only one time and stopping, he is making one step instead of for example 100. Im working with Unity3D. Here is source code;

public class Test01 : MonoBehaviour
{
public float speed, stopDist, rotationSpeed, moveSpeed, minSpeed, maxBackSpeed, maxFrontSpeed, turnSpeed, riseSpeed;
public Transform target;
private Rigidbody rb;
private float currentSpeed;

public bool isFinding = false;
private PlaySound signal;

void Start()
{
    signal = GameObject.FindGameObjectWithTag("Signal").GetComponent<PlaySound>();
    rb = GetComponent<Rigidbody>();
}

private void Update()
{
    // If space key button is pressed the robot's isFinding bool is becaming true and robot is starting searching for target.
    if (Input.GetKeyDown(KeyCode.Space))
    {
        isFinding = true;
        if (Vector3.Distance(transform.position, target.position) > stopDist)
        {
            transform.position = Vector3.MoveTowards(transform.position, target.position, speed * Time.deltaTime);
            signal.isAlarming = true;
            signal.Sound();
        }
        else if (Vector3.Distance(transform.position, target.position) < stopDist)
        {
            isFinding = false;
            signal.isAlarming = false;
            SoundManager.instance.StopSound();
            StopChasing();
        }
    }
}
 public void StopChasing()
{
    transform.position = this.transform.position;
}

Answer 1

Input.GetKeyDown is a function right when you pressed down the key.

You might want to change that to Input.GetKey instead, so it will move everytime you hold space.

Like this,

private void Update()
{
    // If space key button is pressed the robot's isFinding bool is becaming true and robot is starting searching for target.
    if (Input.GetKey(KeyCode.Space))
    {
        isFinding = true;
        if (Vector3.Distance(transform.position, target.position) > stopDist)
        {
            transform.position = Vector3.MoveTowards(transform.position, target.position, speed* Time.deltaTime);
            signal.isAlarming = true;
            signal.Sound();
        }
        else if (Vector3.Distance(transform.position, target.position) < stopDist)
        {
            isFinding = false;
            signal.isAlarming = false;
            SoundManager.instance.StopSound();
            StopChasing();
        }
    }
}

---

If you take the Input.GetKeyDown for the robot to start targetting. Then split it like this

private void Update()
{
    // If space key button is pressed the robot's isFinding bool is becaming true and robot is starting searching for target.
    if (Input.GetKeyDown(KeyCode.Space))
    {
        isFinding = true;
    }
    if (isFinding)
    {
        if (Vector3.Distance(transform.position, target.position) > stopDist)
        {
            transform.position = Vector3.MoveTowards(transform.position, target.position, speed* Time.deltaTime);
            signal.isAlarming = true;
            signal.Sound();
        }
        else if (Vector3.Distance(transform.position, target.position) < stopDist)
        {
            isFinding = false;
            signal.isAlarming = false;
            SoundManager.instance.StopSound();
            StopChasing();
        }
    }
}

---

After all, what you're doing before doesn't really use the isFinding as anything, you'll be just setting it as true and it will do nothing to affect the code.

Answer 2

Well currently you have everything nested under the GetKeyDown so it is executed only exactly once .

You could change that doing

if (Input.GetKeyDown(KeyCode.Space))
{
    isFinding = true;
}

if(isFinding)
{
    if (Vector3.Distance(transform.position, target.position) > stopDist)
    {
        transform.position = Vector3.MoveTowards(transform.position, target.position, speed * Time.deltaTime);
        signal.isAlarming = true;
        signal.Sound();
    }
    else
    {
        isFinding = false;
        signal.isAlarming = false;
        SoundManager.instance.StopSound();
        StopChasing();
    }
}

So pressing Space once activates the isFinding mode until it arrives at Vector3.Distance(transform.position, target.position) < stopDist