Re: x-display-list on the Mac

[David Reitter]

On 24 Mar 2007, at 10:21, YAMAMOTO Mitsuharu wrote:

> > Right, but if you have one X11 screen on two monitors, it should
> > return the total width.  This seems to not be the case when
> > compiling for native OSX.
>
> OK, how about this?  x-display-mm-{width,height} are changed so as to
> keep the dpi values of the main display.

Sure, that would make it a bit more consistent. However, the -mm-  
functions weren't really my concern.
Placing frames is a difficult thing if one doesn't know what the  
available screen area is (screen as in total screen, not in the X  
sense).

What complicates matters is that multiple monitors may be arranged so  
that the total desktop area is not rectangular. Just having  
information about total width and height won't be enough. (And I  
presume that is not a Mac only issue.)

Can the notion of "display" (X) approximate each monitor? In a  
situation with two monitors, one could have x-display-list return  
three displays: a main one ("Mac"), and then "1" and "2" or so for  
the other two, separately. Then, x-display-mm/pixel-width/height  
could either return the dimensions of the total area, or of only one  
of the screens.

This does not yet reflect the fact that the small displays  
(representing monitors) can be positioned anywhere on the big screen  
- maybe a function `x-display-origin' could return the coordinates  
for each small display.