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有时我们只需要网格中顶点的子集即可动画，而无需完整的骨架，例如用于面部动画的一组嘴形或脸部顶点。一种简单的方法是使用“变形目标动画”。在此动画中，我们混合顶点而不是骨骼，这就是为什么它也被称为逐顶点动画的原因。动画存储为原始网格顶点的一系列变形版本。变形版本称为“变形目标”，而原始版本称为“基础”。我们可以使用权重数组在基本目标和变形目标之间进行混合：

通过使用jd文件格式，我们可以在pos0和pos1，normal0和normal1之间进行插值

来自Unity Wiki的以下示例仅使用Lerp在2个网格之间混合顶点：

using UnityEngine;
 /// REALLY IMPORTANT NOTE./// When using the mesh morpher you should absolutely make sure that you turn/// off generate normals automatically in the importer, or set the normal angle to 180 degrees./// When importing a mesh Unity automatically splits vertices based on normal creases./// However the mesh morpher requires that you use the same amount of vertices for each mesh and that/// those vertices are laid out in the exact same way. Thus it wont work if unity autosplits vertices based on normals.[RequireComponent(typeof(MeshFilter))]public class MeshMorpher : MonoBehaviour{   public Mesh[] m_Meshes;
   public bool m_AnimateAutomatically = true;
   public float m_OneLoopLength = 1.0F; /// The time it takes for one loop to complete   public WrapMode m_WrapMode = WrapMode.Loop;
   private float m_AutomaticTime = 0;
 
   private int m_SrcMesh = -1;
   private int m_DstMesh = -1;
   private float m_Weight = -1;
   private Mesh m_Mesh;
 
   /// Set the current morph in       public void SetComplexMorph(int srcIndex, int dstIndex, float t)   {      if (m_SrcMesh == srcIndex && m_DstMesh == dstIndex && Mathf.Approximately(m_Weight, t))         return;
 
      Vector3[] v0 = m_Meshes[srcIndex].vertices;
      Vector3[] v1 = m_Meshes[dstIndex].vertices;
      Vector3[] vdst = new Vector3[m_Mesh.vertexCount];
      for (int i = 0; i < vdst.Length; i++)         vdst[i] = Vector3.Lerp(v0[i], v1[i], t);
 
      m_Mesh.vertices = vdst;
      m_Mesh.RecalculateBounds();
   } 
   /// t is between 0 and m_Meshes.Length - 1.   /// 0 means the first mesh, m_Meshes.Length - 1 means the last mesh.   /// 0.5 means half of the first mesh and half of the second mesh.   public void SetMorph(float t)   {      int floor = (int)t;
      floor = Mathf.Clamp(floor, 0, m_Meshes.Length - 2);
      float fraction = t - floor;
      fraction = Mathf.Clamp(t - floor, 0.0F, 1.0F);
      SetComplexMorph(floor, floor + 1, fraction);
   } 
   void Awake()   {      enabled = m_AnimateAutomatically;
      MeshFilter filter = GetComponent(typeof(MeshFilter)) as MeshFilter;
 
      // Make sure all meshes are assigned!      for (int i = 0; i < m_Meshes.Length; i++)      {         if (m_Meshes[i] == null)         {            Debug.Log("MeshMorpher mesh  " + i + " has not been setup correctly");
            m_AnimateAutomatically = false;
            return;
         }      } 
      //  At least two meshes      if (m_Meshes.Length < 2)      {         Debug.Log("The mesh morpher needs at least 2 source meshes");
         m_AnimateAutomatically = false;
         return;
      } 
      filter.sharedMesh = m_Meshes[0];
      m_Mesh = filter.mesh;
      int vertexCount = m_Mesh.vertexCount;
      for (int i = 0; i < m_Meshes.Length; i++)      {         if (m_Meshes[i].vertexCount != vertexCount)         {            Debug.Log("Mesh " + i + " doesn't have the same number of vertices as the first mesh");
            m_AnimateAutomatically = false;
            return;
         }      }   } 
   void Update()   {      if (m_AnimateAutomatically)      {         float deltaTime = Time.deltaTime * (m_Meshes.Length - 1) / m_OneLoopLength;
         m_AutomaticTime += deltaTime;
         float time;
         if (m_WrapMode == WrapMode.Loop)            time = Mathf.Repeat(m_AutomaticTime, m_Meshes.Length - 1);
         else if (m_WrapMode == WrapMode.PingPong)            time = Mathf.PingPong(m_AutomaticTime, m_Meshes.Length - 1);
         else            time = Mathf.Clamp(m_AutomaticTime, 0, m_Meshes.Length - 1);
 
         SetMorph(time);
      }   }}

转载http://www.cgdev.net/blog/476.html

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