敌方AI移动决策

Question

我正在为Unity platformer游戏开发一个敌人AI移动系统，它将允许敌人在不变的基础上做出三个决定之一:空闲，向右移动，或向左移动。我希望敌人能够选择这些决定中的任何一个，即使它刚刚选择的决定将与它的下一个决定相同(即它可以连续两次选择“向右移动”，或者想要多少次就选择多少次)。下面的脚本没有错误，但当我测试游戏时，它会导致我的敌人结巴。有时它会在瞬间向右移动，然后向左移动，等等。我觉得我的代码的内在逻辑有点正确，但它的实现方式需要一些工作。感谢你能给我的任何帮助。

顺便说一句，如果我把"MakeMovementDecision“函数放在"Start”函数中，敌人会将.07向左或向右移动，或者只是静止不动，而永远不会执行另一个移动函数。

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

public class AIMovement : MonoBehaviour {

// References the enemy's Rigidbody2D component
private Rigidbody2D enemyRigidbody;

// Sets the enemy's movement speed
[SerializeField]
private int movementSpeed;

// Checks if the enemy is moving (to be used with animations)
private bool isMoving;

// The direction in which the enemy will move
private Vector2 directionToMove;

// The random decision (0, 1 or 2) that represents which movement function the enemy will perform
private int decisionValue;

// The time remaining before the enemy chooses which movement function to perform again
private float timeTilNextDecision;

// The random float that will be used to determine for how long the enemy remains idle
private float idleTime;

// The random float that will be used to determine for how long the enemy moves left or right
private float moveTime;

// Use this for initialization
void Start () {

    // Accesses the enemy's Rigidbody2D component
    enemyRigidbody = GetComponent<Rigidbody2D>();
}

void FixedUpdate () {

    MakeMovementDecision();
}

/// <summary>
/// Generates the decision for which type of movement the enemy will perform
/// </summary>
private void MakeMovementDecision ()
{
    // Chooses a value upon which the movement decision will be based
    decisionValue = Random.Range(0, 3);

    switch (decisionValue)
    {
        // Keeps the enemy standing still
        case 0:
            Idle();
            break;

        // Moves the enemy to the right
        case 1:
            MoveRight();
            break;

        // Moves the enemy to the left
        case 2:
            MoveLeft();
            break;
    }
}

/// <summary>
/// Causes the enemy to stand still with idle animations 
/// </summary>
private void Idle ()
{
    // Sets the idle stance duration
    idleTime = Random.Range(5.0f, 10.0f);

    // Calculates the time until the enemy may decide to change its movement
    timeTilNextDecision = idleTime - Time.deltaTime;

    // Sets the movement bool to false to play the idle animations
    isMoving = false;

    // Stops the enemy's movement
    enemyRigidbody.velocity = Vector2.zero;

    // Checks if the enemy should make a decision on its next movement
    if (timeTilNextDecision < 0)
    {
        MakeMovementDecision();
    }

}

private void MoveRight()
{
    moveTime = Random.Range(2.0f, 5.01f);
    timeTilNextDecision = moveTime - Time.deltaTime;
    isMoving = true;
    directionToMove = Vector2.right;
    transform.Translate(directionToMove * (movementSpeed * Time.deltaTime));

    if (timeTilNextDecision < 0)
    {
        MakeMovementDecision();
    }

}

private void MoveLeft()
{
    moveTime = Random.Range(2.0f, 5.01f);
    timeTilNextDecision = moveTime - Time.deltaTime;
    isMoving = true;
    directionToMove = Vector2.left;
    transform.Translate(directionToMove * (movementSpeed * Time.deltaTime));

    if (timeTilNextDecision < 0)
    {
        MakeMovementDecision();
    }

}

}

Answer 1

我想通了。我是一个过度脚本的受害者。这要简单得多，而且做的正是我想要的。关键是timeTilNextMovement变量是决定下一次移动何时发生的唯一变量。在我的另一个脚本中，我使用了太多的变量来完成这个简单的任务。

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

public class EnemyMovement : MonoBehaviour {

private Rigidbody2D enemyRigidbody;

private int movementValue;

private float timeTilNextMovement;

private bool isMoving;

[SerializeField]
private float movementSpeed;

private Vector2 moveRight;
private Vector2 moveLeft;

// Use this for initialization
void Start () {

    enemyRigidbody = GetComponent<Rigidbody2D>();
    moveRight = Vector2.right;
    moveLeft = Vector2.left;

    MakeMovementDecision();
}

// Update is called once per frame
void FixedUpdate () {

    timeTilNextMovement -= Time.fixedDeltaTime;

    switch (movementValue)
    {
        case 0:
            Debug.Log("IDLE"); 
            isMoving = false;
            enemyRigidbody.velocity = Vector2.zero;
            break;
        case 1:
            Debug.Log("RIGHT");
            isMoving = true;
            transform.Translate(moveRight * (movementSpeed * Time.fixedDeltaTime));
            break;
        case 2:
            Debug.Log("LEFT");
            isMoving = true;
            transform.Translate(moveLeft * (movementSpeed * Time.fixedDeltaTime));
            break;
    }

    if (timeTilNextMovement < 0)
    {
        MakeMovementDecision();
    }

}

private void MakeMovementDecision()
{
    movementValue = Random.Range(0, 3);
    timeTilNextMovement = Random.Range(2.0f, 5.0f);
}

}

Answer 2

您需要计算FixedUpdate()内部的时间。你的代码应该看起来像这样；

void FixedUpdate () {
    // Calculates the time until the enemy may decide to change its movement
    moveTime += Time.deltaTime;
    timeTilNextDecision = idleTime - moveTime;

    if (timeTilNextDecision < 0)
    {
        MakeMovementDecision();
    }
}

/// <summary>
/// Generates the decision for which type of movement the enemy will perform
/// </summary>
private void MakeMovementDecision ()
{
    // Chooses a value upon which the movement decision will be based
    decisionValue = Random.Range(0, 3);

    switch (decisionValue)
    {
        // Keeps the enemy standing still
        case 0:
            Idle();
            break;

        // Moves the enemy to the right
        case 1:
            MoveRight();
            break;

        // Moves the enemy to the left
        case 2:
            MoveLeft();
            break;
    }
}

/// <summary>
/// Causes the enemy to stand still with idle animations 
/// </summary>
private void Idle ()
{

    // Sets the idle stance duration
    idleTime = Random.Range(5.0f, 10.0f);
    // Sets the movement bool to false to play the idle animations
    isMoving = false;

    // Stops the enemy's movement
    enemyRigidbody.velocity = Vector2.zero;

    // Checks if the enemy should make a decision on its next movement


}

private void MoveRight()
{
    moveTime = Random.Range(2.0f, 5.01f);
    isMoving = true;
    directionToMove = Vector2.right;
    transform.Translate(directionToMove * (movementSpeed * Time.deltaTime));
}

private void MoveLeft()
{
    moveTime = Random.Range(2.0f, 5.01f);
    isMoving = true;
    directionToMove = Vector2.left;
    transform.Translate(directionToMove * (movementSpeed * Time.deltaTime));
}

编辑:我发现你计算时间的方式是错误的。Time.deltaTime是一个固定参数，它不返回经过的时间。