Avatar捏脸换装

简单说明：

1. 基础换装:Skinned Mesh Renderer组件的bones骨骼信息 去刷新骨骼

2. 合并Mesh:

3. 刷新权重:

4. Bindposes

5. 替换材质，合并贴图，刷新UV

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class CombineMesh{
    public static void Combine(GameObject avatar,SkinnedMeshRenderer[] skinneds,bool mergeSubMeshes)
    {
        //1.取出所有骨骼
        Transform[] allbone = avatar.GetComponentsInChildren<Transform>();
        Dictionary<string, Transform> dicbone = new Dictionary<string, Transform>();
        for (int i = 0; i < allbone.Length; i++)
        {
            dicbone.Add(allbone[i].name, allbone[i]);
        }
        //2.根据是否合并子网格判断是否合并材质
        List<Vector2[]> olduvlist = new List<Vector2[]>();
        Material material = new Material(Shader.Find("Custom/Face"));
        List<Material> materials = new List<Material>();
        if (mergeSubMeshes)
        {
            List<Texture2D> texture2s = new List<Texture2D>();
            for (int i = 0; i < skinneds.Length; i++)
            {
                texture2s.Add(skinneds[i].sharedMaterial.GetTexture("_BackTex") as Texture2D);
            }
            Texture2D texture = new Texture2D(1024, 1024);
            Rect[] rects = texture.PackTextures(texture2s.ToArray(), 0);
            //修改模型uv坐标
            for (int i = 0; i < skinneds.Length; i++)
            {
                Vector2[] olduv = skinneds[i].sharedMesh.uv;
                olduvlist.Add(olduv);
                Vector2[] newuv = new Vector2[olduv.Length];
                for (int j = 0; j < olduv.Length; j++)
                {
                    float uvx = rects[i].x + rects[i].width * olduv[j].x;
                    float uvy = rects[i].y + rects[i].height * olduv[j].y;
                    newuv[j] = new Vector2(uvx, uvy);
                }
                skinneds[i].sharedMesh.uv = newuv;
            }
            Texture2D face = skinneds[0].sharedMaterial.GetTexture("_MainTex") as Texture2D;
            material.SetTexture("_BackTex", texture);
            material.SetTexture("_MainTex", face);
            material.SetFloat("_PosX", texture.width / face.width);
            material.SetFloat("_PosY", texture.height / face.height);
        }
        else
        {
            for (int i = 0; i < skinneds.Length; i++)
            {
                materials.Add(skinneds[i].sharedMaterial);
            }
        }
        //3.取出网格合并
        List<CombineInstance> combines = new List<CombineInstance>();
        for (int i = 0; i < skinneds.Length; i++)
        {
            CombineInstance combine = new CombineInstance();
            combine.mesh = skinneds[i].sharedMesh;
            combine.transform = skinneds[i].transform.localToWorldMatrix;
            combines.Add(combine);
        }
        Mesh mesh = new Mesh();
        mesh.CombineMeshes(combines.ToArray(), mergeSubMeshes, false);
        //4.找到需要使用的骨骼
        List<Transform> bones = new List<Transform>();
        for (int i = 0; i < skinneds.Length; i++)
        {
            for (int j = 0; j < skinneds[i].bones.Length; j++)
            {
                if (dicbone.ContainsKey(skinneds[i].bones[j].name))
                {
                    bones.Add(dicbone[skinneds[i].bones[j].name]);
                }
            }
        }
        //5.赋值
        avatar.GetComponent<SkinnedMeshRenderer>().sharedMesh = mesh;
        avatar.GetComponent<SkinnedMeshRenderer>().bones = bones.ToArray();
        if (mergeSubMeshes)
        {
            avatar.GetComponent<SkinnedMeshRenderer>().material = material;
        }
        else
        {
            avatar.GetComponent<SkinnedMeshRenderer>().materials = materials.ToArray();
        }
    }}