<s>
Xinerama	B-Device
is	O
an	O
extension	O
to	O
the	O
X	B-Operating_System
Window	I-Operating_System
System	I-Operating_System
that	O
enables	O
X	B-Operating_System
applications	O
and	O
window	B-Application
managers	I-Application
to	O
use	O
two	O
or	O
more	O
physical	O
displays	O
as	O
one	O
large	O
virtual	O
display	O
.	O
</s>
<s>
Developed	O
under	O
the	O
name	O
PanoramiX	B-Device
by	O
Madeline	O
T	O
.	O
Asmus	O
of	O
the	O
Digital	O
Equipment	O
Corporation	O
's	O
Unix	O
X	B-Operating_System
Server	O
Engineering	O
Group	O
,	O
the	O
software	O
was	O
contributed	O
to	O
The	B-Application
Open	I-Application
Group	I-Application
for	O
X11	B-Operating_System
Release	O
6.4	O
(	O
X11R6.4	O
)	O
and	O
renamed	O
Xinerama	B-Device
.	O
</s>
<s>
It	O
was	O
then	O
incorporated	O
into	O
the	O
XFree86	B-Device
4.0	O
release	O
in	O
1998	O
and	O
the	O
Solaris	B-Application
7	I-Application
11/99	O
release	O
.	O
</s>
<s>
According	O
to	O
X	B-Operating_System
Server	O
project	O
lead	O
Rob	O
Lembree	O
,	O
the	O
name	O
was	O
inspired	O
by	O
the	O
Cinerama	O
widescreen	O
theatre	O
process	O
.	O
</s>
<s>
Xinerama	B-Device
advantages	O
include	O
the	O
ability	O
to	O
only	O
maximize	O
windows	O
to	O
the	O
dimensions	O
of	O
the	O
active	O
physical	O
display	O
,	O
and	O
to	O
allow	O
new	O
pop-up	O
windows	O
on	O
the	O
active	O
physical	O
display	O
.	O
</s>
<s>
When	O
Xinerama	B-Device
is	O
enabled	O
in	O
the	O
X	B-Operating_System
server	O
,	O
multiple	O
X	B-Operating_System
screens	O
can	O
be	O
unified	O
into	O
a	O
single	O
workspace	O
.	O
</s>
<s>
This	O
unified	O
work	O
area	O
allows	O
windows	O
to	O
be	O
transferred	O
across	O
X	B-Operating_System
screens	O
.	O
</s>
<s>
The	O
Xinerama	B-Device
extension	O
provides	O
clients	O
with	O
information	O
about	O
the	O
layout	O
of	O
viewports	O
within	O
the	O
unified	O
workspace	O
.	O
</s>
<s>
The	O
X	B-Operating_System
server	O
's	O
client/server	O
architecture	O
allows	O
the	O
server	O
to	O
expose	O
Xinerama	B-Device
information	O
to	O
the	O
client	O
regardless	O
of	O
whether	O
the	O
Xinerama	B-Device
infrastructure	O
is	O
active	O
.	O
</s>
<s>
RandR	O
and	O
NVidia	O
's	O
twinview	B-General_Concept
utilize	O
this	O
feature	O
to	O
provide	O
window	B-Application
managers	I-Application
and	O
clients	O
with	O
information	O
about	O
the	O
output	O
layout	O
relative	O
to	O
the	O
framebuffer	O
.	O
</s>
<s>
Xinerama	B-Device
requires	O
that	O
all	O
of	O
the	O
physical	O
screens	O
have	O
the	O
same	O
bit	O
depth	O
.	O
</s>
<s>
For	O
example	O
,	O
an	O
8-bit	O
screen	O
cannot	O
be	O
combined	O
with	O
a	O
16-bit	B-Device
screen	O
.	O
</s>
<s>
In	O
some	O
implementations	O
,	O
OpenGL	B-Application
direct-rendering	O
only	O
works	O
on	O
one	O
screen	O
.	O
</s>
<s>
The	O
Solaris	B-Application
SPARC	O
OpenGL	B-Application
implementation	O
and	O
ATI	O
and	O
nVidia	O
proprietary	O
Linux	O
drivers	O
support	O
hardware-accelerated	O
rendering	O
of	O
all	O
screens	O
in	O
Xinerama	B-Device
mode	O
.	O
</s>
<s>
Xinerama	B-Device
's	O
lack	O
of	O
support	O
for	O
adding	O
or	O
removing	O
screens	O
causes	O
several	O
problems	O
:	O
</s>
<s>
These	O
problems	O
are	O
related	O
to	O
Xinerama	B-Device
's	O
implementation	O
rather	O
than	O
its	O
design	O
,	O
and	O
can	O
be	O
corrected	O
with	O
further	O
development	O
.	O
</s>
<s>
Some	O
window	B-Application
managers	I-Application
and	O
desktop	O
environments	O
have	O
limited	O
awareness	O
of	O
the	O
separate	O
physical	O
screens	O
in	O
Xinerama	B-Device
,	O
so	O
that	O
the	O
desktop	O
is	O
simply	O
stretched	O
over	O
the	O
physical	O
screens	O
instead	O
of	O
arranged	O
as	O
a	O
single	O
large	O
desktop	O
.	O
</s>
<s>
The	O
window	B-Application
manager	I-Application
may	O
place	O
a	O
new	O
window	O
on	O
an	O
unexpected	O
screen	O
,	O
which	O
can	O
be	O
confusing	O
and	O
annoying	O
.	O
</s>
<s>
Xinerama	B-Device
nevertheless	O
offers	O
the	O
advantage	O
that	O
windows	O
can	O
be	O
moved	O
between	O
screens	O
.	O
</s>
<s>
Some	O
window	B-Application
managers	I-Application
assume	O
a	O
rectangular	O
display	O
area	O
,	O
and	O
enforce	O
this	O
by	O
creating	O
excess	O
"	O
dead	O
space	O
"	O
at	O
the	O
edges	O
of	O
a	O
display	O
.	O
</s>
<s>
The	O
window	B-Application
manager	I-Application
needs	O
awareness	O
of	O
Xinerama	B-Device
to	O
avoid	O
placing	O
new	O
windows	O
in	O
this	O
dead	O
space	O
.	O
</s>
