/// <summary> 获取最近点的索引，如果点列表长度为0时，则返回-1。 </summary>
private int GetClosestPointIndex()
{
int closestIndex = -1;
Vector3[] vertices = TransformUtil.CovertTransformsToVertices(m_points);
var polyLine = GeomUtil.GetClosestPolyLineToPoint(transform.position, vertices, m_isClosed);//获取距离当前点最近的边
if (polyLine.startIndex > -1 && polyLine.endIndex > -1)
{
closestIndex = m_isReverseOnStart ? polyLine.startIndex : polyLine.endIndex;
}
return(closestIndex);
}