Unity3d  用鼠标拾取模型的顶点

RaycastHit hit;         Ray ray = Camera.mainCamera.ScreenPointToRay(Input.mousePosition);         if (Physics.Raycast(ray, out hit, 100))         {             spheretransform.position = hit.point;

            //拾取三角面前提是物体含有一个MeshCollider碰撞器             MeshCollider collider = hit.collider as MeshCollider;             if (collider == null||collider.sharedMesh==null)                 return;

            //获取碰撞器所在物体的Mesh网格             Mesh mesh0 = collider.sharedMesh;

            //获取Mesh网格的所有顶点             Vector3[] vertices = mesh0.vertices;

            //获取mesh的三角形索引，这里的索引的就是模型顶点数组的下标             int[] triangles = mesh0.triangles;

            //然后通过hit.triangleIndex(摄像碰撞到的三角形的第一个点的索引)

            //然后+1 ，+2，获取三角形另外两个点的坐标             Vector3 p0 = vertices[triangles[hit.triangleIndex * 3]];             Vector3 p1 = vertices[triangles[hit.triangleIndex * 3 + 1]];             Vector3 p2 = vertices[triangles[hit.triangleIndex * 3 + 2]];             Transform transform = collider.transform;

            //上面的三个顶点是Mesh的本地坐标，需要用模型的Transform进行转换到世界坐标             p0 = transform.TransformPoint(p0);             p1 = transform.TransformPoint(p1);             p2 = transform.TransformPoint(p2);

            //然后设置三个小球的位置到这个三个点，方便调试，呵呵！             GameObject.Find("Sphere1").transform.position = p0;             GameObject.Find("Sphere2").transform.position = p1;             GameObject.Find("Sphere3").transform.position = p2;         }