回调函数的使用案例

1.比如调用回调函数
void x3d_action_extrude :: set_data(x3d_action_section& sec, std::function<void(size_t, x3d_action_section::key_point&)> func);
2.
x3d_action_extrude ac;
auto track_sec = [&](size_t, x3d_action_section::key_point& pt)
{
pt.m_pt += x3d_vector(m_tiebeam.m_across_width, 0, 0);
};
ac.set_data(*sec_begin, track_sec);