<s>
In	O
3D	O
computer	O
graphics	O
,	O
the	O
view	B-General_Concept
frustum	I-General_Concept
(	O
also	O
called	O
viewing	B-General_Concept
frustum	I-General_Concept
)	O
is	O
the	O
region	O
of	O
space	O
in	O
the	O
modeled	O
world	O
that	O
may	O
appear	O
on	O
the	O
screen	O
;	O
it	O
is	O
the	O
field	O
of	O
view	O
of	O
a	O
perspective	B-Architecture
virtual	O
camera	O
system	O
.	O
</s>
<s>
The	O
view	B-General_Concept
frustum	I-General_Concept
is	O
typically	O
obtained	O
by	O
taking	O
a	O
frustum	O
—	O
that	O
is	O
a	O
truncation	O
with	O
parallel	O
planes	O
—	O
of	O
the	O
pyramid	B-General_Concept
of	I-General_Concept
vision	I-General_Concept
,	O
which	O
is	O
the	O
adaptation	O
of	O
(	O
idealized	O
)	O
cone	O
of	O
vision	O
that	O
a	O
camera	O
or	O
eye	O
would	O
have	O
to	O
the	O
rectangular	O
viewports	O
typically	O
used	O
in	O
computer	O
graphics	O
.	O
</s>
<s>
Some	O
authors	O
use	O
pyramid	B-General_Concept
of	I-General_Concept
vision	I-General_Concept
as	O
a	O
synonym	O
for	O
view	B-General_Concept
frustum	I-General_Concept
itself	O
,	O
i.e.	O
</s>
<s>
Viewing-frustum	O
culling	O
is	O
the	O
process	O
of	O
removing	O
from	O
the	O
rendering	O
process	O
those	O
objects	O
that	O
lie	O
completely	O
outside	O
the	O
viewing	B-General_Concept
frustum	I-General_Concept
.	O
</s>
<s>
To	O
make	O
culling	O
fast	O
,	O
it	O
is	O
usually	O
done	O
using	O
bounding	B-Algorithm
volumes	I-Algorithm
surrounding	O
the	O
objects	O
rather	O
than	O
the	O
objects	O
themselves	O
.	O
</s>
<s>
Together	O
this	O
information	O
can	O
be	O
used	O
to	O
calculate	O
a	O
projection	O
matrix	O
for	O
rendering	O
transformation	B-Language
in	O
a	O
graphics	B-General_Concept
pipeline	I-General_Concept
.	O
</s>
