为什么OnMouseDown函数的hit.triangleIndex return -1？

Question

void OnMouseDown()
    {
        if (Input.GetMouseButtonDown(0))
        {
            RaycastHit hit;
            Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
            if (Physics.Raycast(ray, out hit, 1000.0f))
            {
                int[] triangles = transform.GetComponent<MeshFilter>().mesh.triangles;
                if (hit.triangleIndex != -1 && (hit.triangleIndex * 3) < triangles.Length)
    }

当我单击网格上的一个三角形时，有两个三角形使用断点进入函数，但我看到 hit.triangleIndex 是 -1。

在数组三角形中我有 6 个项目：

index 0 = 2
index 1 = 1 
index 2 = 0
index 3 = 2
index 4 = 3
index 5 = 1

Answer 1

Triangle index is only valid if the collider that was hit is a MeshCollider.

RaycastHit.triangleIndex

为什么OnMouseDown函数的hit.triangleIndex return -1？

Why OnMouseDown function the hit.triangleIndex return -1?

c#

unity3d

unity5