[mythtv-users] X: `Ctrl Alt +' to change "screens"?

[John P. Poet]

I use a pcHDTV card with Myth.  Most of the programs I watch are 16:9, but
some are 4:3.

My TV is a Sony XBR700.  It has a 4:3 screen, but will display 16:9 HD material
using a "vertical squeeze" mode.  When ever the TV detects a 540p or 1080i
signal, it automatically goes into this "vertical squeeze" mode.

What I would like is an easy way to swich from 1920x540p to 720x480p within
X.  Is there a way to do that?

I do NOT want a "virtual screen resolution" other than the absolute
resolution for each of these modes.  The man page has:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Virtual xdim ydim

 This optional entry specifies the virtual screen resolution to be
 used. xdim must be a multiple of either 8 or 16 for most drivers, and a
 multiple of 32 when running in monochrome mode. The given value will be
 rounded down if this is not the case. Video modes which are too large for
 the specified virtual size will be rejected. If this entry is not present,
 the virtual screen resolution will be set to accommodate all the valid
 video modes given in the Modes entry. Some drivers/hardware combinations do
 not support virtual screens. Refer to the appropriate driver-specific
 documentation for details.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The behavior the man page describes, is what I see if I try to list both
1920x540p and 720x480p within the same Screen/Display section.  I end up
with a destop which scrolls around in the larger mode.

Another problem is the "DisplaySize" setting (in the Monitor section):

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
DisplaySize width height

 This optional entry gives the width and height, in millimetres, of the
 picture area of the monitor. If given this is used to calculate the
 horizontal and vertical pitch (DPI) of the screen.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This would need to be different depending on which mode the TV is in.

All this tells me that it is unlikely I will be able to switch between these
two modes from within an X session -- Unless there is a command to switch
from one "Screen" to another from within X?

What I appear to need is two different "Monitor" sections, and then two
different "Screen" sections (one for each Monitor).  I can do that, but how
do I run startx and tell it which "Screen" to use?

Thanks,

John