Re: x-display-pixel-width/height inconsistency

[YAMAMOTO Mitsuharu <mituharu@math.s.chiba-u.ac.jp>]

>>>>> On Thu, 21 Mar 2013 06:43:28 +0400, Dmitry Gutov <dgutov@yandex.ru> said:

> With them fixed, the behavior seems to be right:

ELISP> (x-display-pixel-height)
> 1200
ELISP> (x-display-pixel-width)
> 3200
ELISP> (display-mm-height)
> 423
ELISP> (display-mm-width)
> 1128

> That's the correct values for the bounding box. At least, the first
> two.

Thanks again for testing.

>> I understand users want to know the size of each monitor rather
>> than the total size.  But that does not justify changing existing
>> common functions in an inconsistent and ad hoc way and making them
>> platform-specific unnecessarily.  If such functionality is
>> necessary, it should be provided in a platform-independent and
>> consistent way.

> Of course. I was just asking why you picked this specific behavior
> to make consistent across platforms.

> If the existing X11 behavior is actually in use somewhere, then that
> makes sense, of course.

Other behavior is also OK with me as long as it is consistent across
platforms.  But I think the X11 behavior is the most natural (I won't
say useful) choice at this moment for the following reasons.

First, the behavior is documented in the info including the case for
multi-monitor setups.  Second, the other x-display-* functions query
properties per "display" (in the X11 terminology) determined by the
given argument.  Note that neither of "display" nor "screen" in the
X11 terminology has something to do with physical monitors (in this
sense, the implementation of x-display-screens in the NS port,
counting the number of physical monitors, is also wrong).  Third, I
guess distinguishing physical monitors on X11 requires the Xinerama
extension or some help of window managers.  So such functionality
seems to be at a different level from other x-display-* functions.

One may want to query not only the size of a particular physical
monitor but also the position and the displayable area (i.e., except
Panel, Dock, or Taskbar).  I think it would be better to provide the
functions that are aware of physical monitors as a new group of them,
rather than by breaking the existing argument convention of
x-display-* functions.

				     YAMAMOTO Mitsuharu
				mituharu@math.s.chiba-u.ac.jp