Unity3d 用鼠标拾取模型顶点 三

using UnityEngine;
using System.Collections;
public class DrawBox : MonoBehaviour {
public GameObject sphere1;
// Update is called once per frame
void Update () {
RaycastHit hit;
Ray ray = Camera.mainCamera.ScreenPointToRay(Input.mousePosition);
if (Physics.Raycast(ray, out hit, 100))
{
Debug.Log(hit.collider.gameObject.name);
MeshCollider collider = hit.collider as MeshCollider;
if (collider == null||collider.sharedMesh==null)
return;
Mesh mesh0 = collider.sharedMesh;
Vector3[] vertices = mesh0.vertices;
int[] triangles = mesh0.triangles;
Vector3 p0 = hit.transform.TransformPoint(vertices[triangles[hit.triangleIndex * 3]]);
Vector3 p1 = hit.transform.TransformPoint(vertices[triangles[hit.triangleIndex * 3+1]]);
Vector3 p2 = hit.transform.TransformPoint(vertices[triangles[hit.triangleIndex * 3+2]]);
sphere1.transform.position = MinDistanceMouse(p0, p1, p2);
}
}
Vector3 MinDistanceMouse(Vector3 v1, Vector3 v2, Vector3 v3)
{
Vector3 mouseposition = Input.mousePosition;
float distance1 = Vector3.Distance(v1, mouseposition);
float distance2 = Vector3.Distance(v2, mouseposition);
float distance3= Vector3.Distance(v3, mouseposition);
if (distance1 < distance2 && distance1 < distance3)
return v1;
if (distance2 < distance1 && distance2 < distance3)
return v2;
if (distance3 < distance1 && distance3 < distance2)
return v3;
return Vector3.zero;
}
}