OK, I'm not a programmer but this can be a clue what other players do. I know that programmers know about this, but I do not know why don't they do it.
I know that many users asked for subtitles on video bottom and that this is like a gazillionth time that someone asks for such a request, but for programmers this is not a ahrd thing to do.
As much as I know, almost every program is based on windowed and full screen mode. So, there shoud be a written code for transparent overlay that will track windows size and full screen (full screen - based on windows/monitor resolution).
On that basis, subtitles can be put in any X-Y postition of video.
I've seen that every program or external codec package do it and there are options for that. Even if there are no options for overlay, they do it by default.
Well?