True FPS Aiming problem

Hi, i created a forum post detailling my problem

In short, when I change the player camera to the camera that is in the gun, it begins to point to the floor automatically.
(The problem shown in a video in thethread.)

I suspect it is a conceptual problem and I’m not considering something important.
Or what I’m trying to do is not possible.
I do not know in which section this question should be, but I’m doing the camera blend in C++ and I am using c ++ for my project, so I put the question in C++ programing.

Thanks in advance!

solved my problem. thx