Unity3D创建圆柱体的方法

//圆柱体是由两个圆和一个长方形组成的 先输入长方形的顶点 然后在输入圆顶点 private void UpdateMesh(Mesh mesh,int edg_x, int edg_y, float rad, float len) {  edg_x = Mathf.Max(2, edg_x);//保证最低2个边  edg_y = Mathf.Max(2, edg_y);  int _deglen = (edg_x +1)*edg_y;//长方体  int totalcount = _deglen + (1 + edg_x + 1) * 2; //加两个圆    Vector3[] normals = new Vector3[totalcount];  Vector3[] verts = new Vector3[totalcount];  Vector2[] uvs = new Vector2[totalcount];  int[] trians = new int[edg_x * edg_y*6];   float reg = 6.28318f / edg_x;  float _len = len / (edg_y - 1);      for (int y = 0; y < edg_y; y++)   for (int x = 0; x < edg_x + 1; x++)//多一个边来保存UV值   {    int i = x + y * (edg_x + 1);    verts[i] = new Vector3(Mathf.Sin((reg * (x % edg_x)) % 6.28318f) * rad, Mathf.Cos((reg * (x % edg_x)) % 6.28318f) * rad, rightPos + y * _len);//计算顶点坐标    normals[i] = new Vector3(verts[i].x, verts[i].y, 0);//计算法线方向    int id = x % (edg_x + 1) * 6 + y * edg_x * 6;    if (x < edg_x + 1 && y < edg_y - 1 && (id + 5) < trians.Length)//计算顶点数组    {     if(length>0)     {      trians[id] = i;      trians[id + 1] = trians[id + 4] = i + edg_x + 1;      trians[id + 2] = trians[id + 3] = i + 1;      trians[id + 5] = i + edg_x + 2;     }     else     {      trians[id] = i;      trians[id + 1] = trians[id + 3] = i + 1;      trians[id + 2]= trians[id + 5]=i + edg_x + 1;      trians[id + 4] = i + edg_x + 2;     }         }    //if (edg_x != 2)//计算UV，考虑到2个边的情况    // uvs[i] = new Vector2(x == edg_x ? 1f : quaduvStep.x * x, y == edg_y - 1 ? (2*rad+len)/totalLen : quaduvStep.y * y);    //else    // uvs[i] = new Vector2(x % edg_x, y == edg_y - 1 ? (2 * rad + len) / totalLen : quaduvStep.y * y);   }    int maxId = edg_x * (edg_y - 1) * 6;  verts[_deglen] = new Vector3(0,0,rightPos);    normals[_deglen] = -Vector3.forward;   //uvs[_deglen] = new Vector2(0.5f, (rad) / totalLen);  //原点一面  for (int x = 0; x < edg_x+1 ; x++)  {   verts[_deglen + 1 + x] = new Vector3(Mathf.Sin((reg * (x % edg_x)) % 6.28318f) * rad, Mathf.Cos((reg * (x % edg_x)) % 6.28318f) * rad, rightPos);   normals[_deglen + 1 + x] = -Vector3.forward;   if (x == edg_x) continue;    if(length>0)   {    trians[3 * x + maxId] = _deglen;    trians[3 * x + 1 + maxId] = _deglen + 1 + x;    trians[3 * x + 2 + maxId] = _deglen + 2 + x;   }   else   {    trians[3 * x + maxId] = _deglen;    trians[3 * x + 1 + maxId] = _deglen + 2 + x;    trians[3 * x + 2 + maxId] = _deglen + 1 + x;   }  }    //远点一面  maxId += 3 * edg_x;  verts[_deglen + 2 + edg_x] = new Vector3(0, 0, leftPos);  normals[_deglen + 2 + edg_x] = Vector3.forward;  //uvs[_deglen + 1] = new Vector2(0.5f, (3 * rad + len) / totalLen);    for (int x = 0; x < edg_x+1; x++)  {   verts[1 + x+edg_x+2+ _deglen] =new Vector3(Mathf.Sin((reg * (x % edg_x)) % 6.28318f) * rad, Mathf.Cos((reg * (x % edg_x)) % 6.28318f) * rad,leftPos);   normals[1 + x + edg_x + 2 + _deglen] = Vector3.forward;   if (x == edg_x) continue;   if (length > 0)   {    trians[3 * x + maxId] = _deglen + 2 + edg_x;    trians[3 * x + 1 + maxId] = _deglen + 2 + edg_x + x + 2;    trians[3 * x + 2 + maxId] = _deglen + 2 + edg_x + x + 1;   }   else   {    trians[3 * x + maxId] = _deglen + 2 + edg_x;    trians[3 * x + 1 + maxId] = _deglen + 2 + edg_x + x + 1;    trians[3 * x + 2 + maxId] = _deglen + 2 + edg_x + x + 2;   }  }  mesh.Clear();  mesh.vertices = verts;  mesh.triangles = trians;  //mesh.uv = uvs;  mesh.normals = normals;  mesh.RecalculateBounds(); }