vlc-playing DVD won't display on external monitor

[Chris]

2008/10/24 Robert P. J. Day <rpjday at crashcourse.ca>:
>  someone else suggested that the DVD image was bypassing the
> framebuffer, which i didn't follow.  can someone clarify the
> technical issues behind why i need to deactivate the attached
> LCD display on the laptop to get DVD output on the external
> display?  i'm convinced it works, and now i know how to do it.
> i'd just like it to not be quite so much magic.  thanks.

I'm not sure about this but I suspect the video display may be using a
video overlay surface:

http://en.wikipedia.org/wiki/Video_overlay

Typically you can only have one overlay surface per graphics device,
not per screen. As I said I'm not sure if that's what's happening for
you but it's a likely possibility.

Chris.