Unity 伤害飘血效果

• 前言
• 一、效果演示
• 二、相关代码

一个对于战斗中飘字飘血的功能，比较简单。

字的颜色没调整好，所以有点不好看。

根据自定义曲线控制飘字效果

using LFrameWork;
using TMPro;
using UnityEngine;

namespace Game
{
    public class HUDText : LMonoBehaviour,IUpdate
    {
        private readonly Vector3 r_LifeBarOffsetY = new Vector3(0, 2.2f, 0);

        //飘字持续时间
        [Range(0, 10f)] [SerializeField] protected float m_DurationTime;
        [SerializeField] protected AnimationCurve m_AlphaCurve;
        [SerializeField] protected AnimationCurve m_ScaleCurve;
        [SerializeField] protected AnimationCurve m_OffsetXCurve;
        [SerializeField] protected AnimationCurve m_OffsetYCurve;

        protected Transform m_FollowPlayer;
        protected TMP_Text m_HUDText;
        protected float m_CurrentTime;

        protected float m_OriginX;
        protected float m_OriginY;
        
        public void SetData(Transform target, string info)
        {
            m_FollowPlayer = target;
            m_HUDText = GetComponent();
            m_HUDText.text = info;

			//设置文本的起始位置
            transform.position =
                Utils.GetScreenPos(Camera.current, m_FollowPlayer.position + r_LifeBarOffsetY);
            
            m_OriginX = transform.localPosition.x;
            m_OriginY = transform.localPosition.y;
            
            //加入到自定义生命周期控制中
            LifeCycleManager.Instance.AddUpdate(this);
        }

        private void OnDisable()
        {
            LifeCycleManager.Instance.RemoveUpdate(this);
        }

        public void UpdateFun()
        {
            m_CurrentTime += Time.deltaTime;
            var tmpPercent = m_CurrentTime / m_DurationTime;
            if (tmpPercent > 1f)
            {
                //对象池回收
                RPGGame.Instance.RecycleObject(gameObject);
                return;
            }
            //静态扩展方法
            m_HUDText.SetColorAlpha(m_AlphaCurve.Evaluate(tmpPercent));
            transform.localScale = Vector3.one * m_ScaleCurve.Evaluate(tmpPercent);
            transform.SetTransLocalPosX(m_OriginX + m_OffsetXCurve.Evaluate(tmpPercent));
            transform.SetTransLocalPosY(m_OriginY + m_OffsetYCurve.Evaluate(tmpPercent));
        }
    }
}

工具方法，世界坐标和屏幕坐标的转换

        public static Vector3 GetScreenPos(Camera camera, Vector3 worldPos)
        {
            var tmpScreenPos = RectTransformUtility.WorldToScreenPoint(camera, worldPos);
            return new Vector3(tmpScreenPos.x, tmpScreenPos.y, 0);
        }

对于颜色渐变效果：
因为我这里的文本用的是TextMeshPro组件，所以对于字体变色可以直接修改其对应的属性。来控制文本的颜色渐变。

对于老版的Text组件，这里贴上一个脚本。在生成网格时修改顶点颜色，达成渐变的效果

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

namespace Game
{
    public class TextGradient : BaseMeshEffect
    {
        public Color32 topColor = Color.white;
        public Color32 bottomColor = Color.black;

        public override void ModifyMesh(VertexHelper vh)
        {
            if (!IsActive() || vh.currentVertCount == 0) return;
            
            var tmpVertices = new List();
            vh.GetUIVertexStream(tmpVertices);
            
            for (var i = 0; i < tmpVertices.Count && tmpVertices.Count - i >= 6; i += 6)
            {
                ChangeColor(tmpVertices,i, topColor);
                ChangeColor(tmpVertices,i + 1, topColor);
                ChangeColor(tmpVertices,i + 2, bottomColor);
                ChangeColor(tmpVertices,i + 3, bottomColor);
                ChangeColor(tmpVertices,i + 4, bottomColor);
                ChangeColor(tmpVertices,i + 5, topColor);
            }
            
            vh.Clear();
            vh.AddUIVertexTriangleStream(tmpVertices);
        }   

        private void ChangeColor(List uiVertices,int index, Color color)
        {
            var tmpVertex = uiVertices[index];
            tmpVertex.color *= color;
            uiVertices[index] = tmpVertex;
        }
    }
}

在文本上添加此脚本以后，修改TopColor和BottomColor脚本也可以实现渐变的效果

最后再分享一下自己调的四种曲线

AlphaCurve

ScaleCurve

OffsetXCurve

OffsetYCurve