<s>
Room-scale	O
(	O
sometimes	O
written	O
without	O
the	O
dash	O
)	O
is	O
a	O
design	O
paradigm	O
for	O
virtual	B-Application
reality	I-Application
(	O
VR	O
)	O
experiences	O
which	O
allows	O
users	O
to	O
freely	O
walk	O
around	O
a	O
play	O
area	O
,	O
with	O
their	O
real-life	O
motion	O
reflected	O
in	O
the	O
VR	O
environment	O
.	O
</s>
<s>
Using	O
360	O
degree	O
tracking	B-Operating_System
equipment	O
such	O
as	O
infrared	O
sensors	O
,	O
the	O
VR	O
system	O
monitors	O
the	O
user	O
's	O
movement	O
in	O
all	O
directions	O
,	O
and	O
translates	O
this	O
into	O
the	O
virtual	O
world	O
in	O
real-time	O
.	O
</s>
<s>
The	O
HTC	O
Vive	O
virtual-reality	B-Application
system	O
incorporates	O
room-scale	O
tracking	B-Operating_System
in	O
its	O
core	O
design	O
,	O
using	O
two	O
infrared	O
tracking	B-Operating_System
stations	O
located	O
in	O
opposite	O
corners	O
of	O
the	O
room	O
to	O
monitor	O
the	O
movement	O
of	O
the	O
player	O
.	O
</s>
<s>
The	O
Oculus	B-Device
Rift	I-Device
VR	O
system	O
was	O
introduced	O
primarily	O
for	O
front	O
facing	O
180	O
degree	O
experiences	O
.	O
</s>
<s>
However	O
,	O
Oculus	O
now	O
supports	O
two	O
sensor	O
diagonal	O
placement	O
roomscale	B-General_Concept
or	O
users	O
can	O
purchase	O
a	O
third	O
sensor	O
to	O
enable	O
more	O
robust	O
room-scale	O
tracking	B-Operating_System
,	O
</s>
