[xine-bugs] [ xine-Bugs-1001702 ] Not possible to select display aspect ratio

[SourceForge.net <no...@so...>]

Bugs item #1001702, was opened at 2004-08-02 00:06
Message generated for change (Comment added) made by jstembridge
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=109655&aid=1001702&group_id=9655

Category: None
Group: None
Status: Open
Resolution: None
Priority: 4
Submitted By: Lasse Kärkkäinen (tronic)
Assigned to: Nobody/Anonymous (nobody)
Summary: Not possible to select display aspect ratio

Initial Comment:
Xine always uses DPI values from X. This is a problem
because in many configurations it is practically
impossible to get those DPI values correct. Add
user-configurable display pixel aspect and
desktop/display aspect ratio settings (both are
required, but only one may be set at a time). Of
course, the special case of 1:1 pixel aspect would help
a lot already (because it applies to nearly all PC
displays).


----------------------------------------------------------------------

>Comment By: James Stembridge (jstembridge)
Date: 2004-09-08 15:50

Message:
Logged In: YES 
user_id=537148

According to the XF86Config man page the DisplaySize is set 
in the Monitor section. This being the case why can't it be 
set independently for each monitor?

----------------------------------------------------------------------

Comment By: Lasse Kärkkäinen (tronic)
Date: 2004-09-08 15:36

Message:
Logged In: YES 
user_id=57635

Did you read my post? It's a dual-display setup, with two
monitors. This is a problem because it is NOT possible to
configure DisplaySize separately for each display. Also, a
combined DisplaySize doesn't make any sense, as each monitor
probably has different DPI. In fact, I don't know if X or
Xinerama even could handle this, but the NVIDIA driver
certainly cannot. The combined desktop mode (TwinView) is
clearly implemented in NVIDIA drivers, not by X (I don't
think X even supports any kind of combined desktop directly).

Just add a selection for square pixels (pixel aspect = 1.0)
and it'll work in most configurations.

In fact, that's what I've been using, but doing so requires
hacking the source, and has some issues (window size is
calculated with the incorrect aspect, probably because the
pixel aspect override is done in the wrong function).

Conclusion: the bug is a combination of X limitations and of
NVIDIA hacks to get around those. Fixing the actual problem
seems impossible, as it would require adding major new
functionality to X. Thus, a workaround must be supported in
every program that makes use of the DPI values provided by
X. Most programs already allow manual DPI overrides.


----------------------------------------------------------------------

Comment By: Michael Roitzsch (mroi)
Date: 2004-08-25 15:46

Message:
Logged In: YES 
user_id=552060

Sorry, but I still don't quite get it. The DisplaySize in X11 is a 
physical size and is configured per physical monitor. I don't 
understand how using a monitor in different logical screens or 
with different resolutions can change its phyiscal size. 
 
Maybe you actually see a bug in your graphics driver? 
 

----------------------------------------------------------------------

Comment By: Lasse Kärkkäinen (tronic)
Date: 2004-08-25 07:47

Message:
Logged In: YES 
user_id=57635

In TwinView (dual display) there is no way to configure
separate DisplaySize for each display. Even if it is
possible to get the DPI correct for one of the two displays,
this will only work in one resolution. After switching
resolutions (xrandr), it will be incorrect again. This seems
to be a limitation with X, and I am not aware of any useful
workarounds.



----------------------------------------------------------------------

Comment By: Michael Roitzsch (mroi)
Date: 2004-08-02 12:44

Message:
Logged In: YES 
user_id=552060

Why would it be impossible to get X report correct DPI values? You just 
have to configure the physical size of your display correctly. 

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=109655&aid=1001702&group_id=9655