十三.角色生命等属性控制

角色生命等属性控制

1.添加UI界面

鼠标右键---->UI---->Canvas，重命名为UICanvas

EventSystem放置在UICanvas下

在UICanvas下添加Image，命名为Heart1，设置图片为UI_Heart

拷贝2个Heart1，共3个心形代表角色生命值

设置UI对齐方式为左上角

2.创建脚本UIController

绑定到UICanvas

创建单例instance，在在Awake中指向UIController

//单例
public static UIController sInstance;    

private void Awake()
{
    sInstance = this;
}

添加引用UI

using UnityEngine.UI;

创建3个Image，分别指向Heart1，Heart2，Heart3

创建3个Sprite，表示满血、半血和空血，指向三个sprite

public Image heart1, heart2, heart3;    //三个生命值状态标识
public Sprite heartFull, heartHalf, heartEmpty;    //生命值状态

新建函数UpdateHealthDisplay，更新生命值状态

public void UpdateHealthDisplay()
{
    switch(PlayerHealthController.sInstance.currentHealth)
    {
        case 6:
            heart1.sprite = heartFull;
            heart2.sprite = heartFull;
            heart3.sprite = heartFull;

            break;
        case 5:
            heart1.sprite = heartFull;
            heart2.sprite = heartFull;
            heart3.sprite = heartHalf;

            break;
        case 4:
            heart1.sprite = heartFull;
            heart2.sprite = heartFull;
            heart3.sprite = heartEmpty;

            break;
        case 3:
            heart1.sprite = heartFull;
            heart2.sprite = heartHalf;
            heart3.sprite = heartEmpty;

            break;
        case 2:
            heart1.sprite = heartFull;
            heart2.sprite = heartEmpty;
            heart3.sprite = heartEmpty;

            break;
        case 1:
            heart1.sprite = heartHalf;
            heart2.sprite = heartEmpty;
            heart3.sprite = heartEmpty;

            break;
        case 0:
            heart1.sprite = heartEmpty;
            heart2.sprite = heartEmpty;
            heart3.sprite = heartEmpty;

            break;
        default:
            heart1.sprite = heartEmpty;
            heart2.sprite = heartEmpty;
            heart3.sprite = heartEmpty;

            break;
    }
}

在PlayerHealthController中，player绑定中maxHealth改为6，overrides---->Apply All

DealDamage函数内同步生命值状态显示

public void DealDamage()
{
    currentHealth --;

    if(currentHealth <= 0)
    {
        currentHealth = 0;
        //生命值耗尽，设置角色隐藏
        gameObject.SetActive(false);
    }

    //同步生命值状态显示
    UIController.sInstance.UpdateHealthDisplay();
}

3.设置受到伤害后一段时间无敌

添加无敌状态的一些参数

//防止连续受到伤害，设置受到伤害后，一段时间无敌状态
public float invincibleLength;  //无敌时间
private float invincibleCounter;    //无敌计数器

//设置无敌状态时角色的显示变化
private SpriteRenderer theSR;

//Start()中初始化
theSR = GetComponent<SpriteRenderer>();

设置invincibleLength为1，在Update中更新invincibleCounter

void Update()
{
    if (invincibleCounter > 0)
    {
        invincibleCounter -= Time.deltaTime;

        if(invincibleCounter <= 0)
        {
            theSR.color = new Color(theSR.color.r, theSR.color.g, theSR.color.b, 1.0f);
        }
    }
}

被攻击时，也同步判断和设置

public void DealDamage()
{
    if (invincibleCounter <= 0)
    {
        currentHealth--;

        if (currentHealth <= 0)
        {
            currentHealth = 0;
            //生命值耗尽，设置角色隐藏
            gameObject.SetActive(false);
        }
        else
        {
            invincibleCounter = invincibleLength;
            theSR.color = new Color(theSR.color.r, theSR.color.g, theSR.color.b, .5f);
        }

        //同步生命值状态显示
        UIController.sInstance.UpdateHealthDisplay();
    }
}

4.受伤后状态

在PlayerController中添加参数

//受伤状态
public float knockBackLength;   //推动时间长
public float knockBackForce;    //推动力量
private float knockBackCounter; //推动计数器

设置初始值

在Update中添加判断

void Update()
{
    if (knockBackCounter <= 0)
    {
        //设置速度 /*GetAxisRaw*/
        theRB.velocity = new Vector2(moveSpeed * Input.GetAxis("Horizontal"), theRB.velocity.y);

        //检测是否在地面       参数：圆形中心，圆形半径，筛选器（用于检查仅在指定层上的对象）
        isGrounded = Physics2D.OverlapCircle(groundCheckPoint.position, .2f, whatIsGround);

        if (isGrounded)
        {
            //在地面时，可以连跳为true
            canDoubleJump = true;
        }

        //跳跃
        if (Input.GetButtonDown("Jump"))
        {
            if (isGrounded)  //判断是否在地面
            {
                theRB.velocity = new Vector2(theRB.velocity.x, jumpForce);
            }
            else
            {
                if (canDoubleJump)
                {
                    //不在地面，连跳
                    theRB.velocity = new Vector2(theRB.velocity.x, jumpForce);
                    canDoubleJump = false;
                }
            }
        }

        //翻转
        if (theRB.velocity.x < 0)
        {
            theSR.flipX = true;
        }
        else if (theRB.velocity.x > 0)
        {
            theSR.flipX = false;
        }
    }
    else
    {
        knockBackCounter -= Time.deltaTime;
        if(!theSR.flipX)
        {
            theRB.velocity = new Vector2(-knockBackForce, theRB.velocity.y);
        }
        else
        {
            theRB.velocity = new Vector2(knockBackForce, theRB.velocity.y);
        }
    }

    //设置动画中设置的moveSpeed,isGrounded的值
    anim.SetFloat("moveSpeed", Mathf.Abs(theRB.velocity.x));
    anim.SetBool("isGrounded", isGrounded);
}

添加KnockBack()函数，设置受伤后推动值

public void KnockBack()
{
	  knockBackCounter = knockBackLength;
    theRB.velocity = new Vector2(0, knockBackForce);
}

在PlayerHealthController中，DealDamage()函数判断当前生命值大于0时，添加推动状态(else下)

//角色受伤后推动状态
PlayerController.sInstance.KnockBack();

5.受伤动画

添加受伤动画

交叉设置动画帧

新建Trigger，命名为"hurt"

设置连接动画

其他状态到受伤状态

受伤状态到正常状态

PlayerController中，KnockBack()函数里面，添加受伤触发动画

//受伤动画
anim.SetTrigger("hurt");