前言

看见很多游戏有很特殊的波浪形文字效果，于是来尝试一下控制TMP文字顶点的方式达到类似效果。

原理

挂载tmp text，在里面随便放入非空格字符。

tmp text组件开放了textInfo接口，也就是GetComponent<TextMeshProUGUI>().textInfo可以获取text字符串信息：

 characterInfo[i].vertexIndex用于找到这个字符起始index；meshInfo[TMP_CharacterInfo.materialReferenceIndex]用于获取mesh信息，再进一层meshInfo.vertices即可拿到顶点信息。

我们就是强行修改vertices信息，然后调用TextMeshProUGUI.UpdateVertexData()即可完成text不同字符间的修改。

保存原始字符顶点vertices信息

//tmp组件
TextMeshProUGUI m_txtSelf = null;
//移动周期
float m_moveTotalTime = 1f;
//上下浮动幅度
float m_amplitude = 100;
Vector3[] m_rawVertex;

public void Awake()
{
    m_txtSelf = transform.GetComponent<TextMeshProUGUI>();
}

private void GetRawVertex()
{
    m_txtSelf.ForceMeshUpdate();
    if (m_txtSelf.textInfo.characterCount > 0)
    {
        TMP_CharacterInfo charInfo = m_txtSelf.textInfo.characterInfo[0];
        TMP_MeshInfo meshInfo = m_txtSelf.textInfo.meshInfo[charInfo.materialReferenceIndex];
        //创建对象来保存初始值
        m_rawVertex = new Vector3[meshInfo.vertices.Length];
        for (int i = 0; i < meshInfo.vertices.Length; i++)
        {
            m_rawVertex[i] = new Vector3(meshInfo.vertices[i].x, meshInfo.vertices[i].y, meshInfo.vertices[i].z);
        }
    }
}

public void Start()
{
    GetRawVertex();
}

所有字符一起移动

用协程每隔一段时间做一次循环运动，用dotween.to附加lamda表达式来完成字符串移动：

public void Start()
{
    GetRawVertex();
    StartCoroutine(Shake());
}
public IEnumerator Shake()
{
    while(true)
    {
        Tweener tweener = DOTween.To(() => 0f, y =>
        {
            for (int i = 0; i < m_txtSelf.textInfo.characterCount; i++)
            {
                // 获取字符信息和MeshInfo
                TMP_CharacterInfo currentCharInfo = m_txtSelf.textInfo.characterInfo[i];
                TMP_MeshInfo meshInfo = m_txtSelf.textInfo.meshInfo[currentCharInfo.materialReferenceIndex];

                int nextVertexIndex = meshInfo.vertices.Length;
                if (i < m_txtSelf.textInfo.characterCount - 1)
                {
                    TMP_CharacterInfo nextCharInfo = m_txtSelf.textInfo.characterInfo[i + 1];
                    nextVertexIndex = nextCharInfo.vertexIndex;
                }

                // 获取起始顶点索引
                int vertexIndex = currentCharInfo.vertexIndex;

                // 顶点偏移
                for (int j = vertexIndex; j < nextVertexIndex; j++)
                {
                    float yOffset = y;
                    if (yOffset >= 0 && yOffset <= 1)
                    {
                        meshInfo.vertices[j] = m_rawVertex[j] + Mathf.Sin(yOffset * Mathf.PI) * Vector3.up * m_amplitude;
                    }
                }
            }
            m_txtSelf.UpdateVertexData();
        }, 2, m_moveTotalTime);

        yield return new WaitForSeconds(m_moveTotalTime);
    }
}

 效果如下显示：

 每个字符规律跳动

就需要在y->yOffset中加入位置参数变量，用以形成类波浪效果：

float yOffset = y - (float)i / m_txtSelf.textInfo.characterCount;

 至此即可完成。

全部代码

using System.Collections;
using UnityEngine;
using TMPro;
using DG.Tweening;

public class test : MonoBehaviour
{
    //tmp组件
    TextMeshProUGUI m_txtSelf = null;
    //移动周期
    float m_moveTotalTime = 1f;
    //上下浮动幅度
    float m_amplitude = 100;
    Vector3[] m_rawVertex;

    public void Awake()
    {
        m_txtSelf = transform.GetComponent<TextMeshProUGUI>();
    }

    private void GetRawVertex()
    {
        m_txtSelf.ForceMeshUpdate();
        if (m_txtSelf.textInfo.characterCount > 0)
        {
            TMP_CharacterInfo charInfo = m_txtSelf.textInfo.characterInfo[0];
            TMP_MeshInfo meshInfo = m_txtSelf.textInfo.meshInfo[charInfo.materialReferenceIndex];
            //创建对象来保存初始值
            m_rawVertex = new Vector3[meshInfo.vertices.Length];
            for (int i = 0; i < meshInfo.vertices.Length; i++)
            {
                m_rawVertex[i] = new Vector3(meshInfo.vertices[i].x, meshInfo.vertices[i].y, meshInfo.vertices[i].z);
            }
        }
    }

    public void Start()
    {
        GetRawVertex();
        StartCoroutine(Shake());
    }
    public IEnumerator Shake()
    {
        yield return new WaitForSeconds(1);
        while (true)
        {
            Tweener tweener = DOTween.To(() => 0f, y =>
            {
                for (int i = 0; i < m_txtSelf.textInfo.characterCount; i++)
                {
                    // 获取字符信息和MeshInfo
                    TMP_CharacterInfo currentCharInfo = m_txtSelf.textInfo.characterInfo[i];
                    TMP_MeshInfo meshInfo = m_txtSelf.textInfo.meshInfo[currentCharInfo.materialReferenceIndex];

                    int nextVertexIndex = meshInfo.vertices.Length;
                    if (i < m_txtSelf.textInfo.characterCount - 1)
                    {
                        TMP_CharacterInfo nextCharInfo = m_txtSelf.textInfo.characterInfo[i + 1];
                        nextVertexIndex = nextCharInfo.vertexIndex;
                    }

                    // 获取起始顶点索引
                    int vertexIndex = currentCharInfo.vertexIndex;

                    // 顶点偏移
                    for (int j = vertexIndex; j < nextVertexIndex; j++)
                    {
                        float yOffset = y - (float)i / m_txtSelf.textInfo.characterCount;
                        if (yOffset >= 0 && yOffset <= 1)
                        {
                            meshInfo.vertices[j] = m_rawVertex[j] + Mathf.Sin(yOffset * Mathf.PI) * Vector3.up * m_amplitude;
                        }
                    }
                }
                m_txtSelf.UpdateVertexData();
            }, 2, m_moveTotalTime);

            yield return new WaitForSeconds(m_moveTotalTime);
        }
    }
}