<s>
A	O
wire-frame	B-Algorithm
model	I-Algorithm
,	O
also	O
wireframe	B-Algorithm
model	I-Algorithm
,	O
is	O
a	O
visual	O
representation	O
of	O
a	O
three-dimensional	O
(	O
3D	O
)	O
physical	O
object	O
used	O
in	O
3D	O
computer	O
graphics	O
.	O
</s>
<s>
Using	O
a	O
wire-frame	B-Algorithm
model	I-Algorithm
allows	O
for	O
the	O
visualization	O
of	O
the	O
underlying	O
design	O
structure	O
of	O
a	O
3D	O
model	O
.	O
</s>
<s>
Traditional	O
two-dimensional	O
views	O
and	O
drawings/renderings	O
can	O
be	O
created	O
by	O
the	O
appropriate	O
rotation	O
of	O
the	O
object	O
,	O
and	O
the	O
selection	O
of	O
hidden	B-Algorithm
line	I-Algorithm
removal	I-Algorithm
via	O
cutting	O
planes	O
.	O
</s>
<s>
Since	O
wire-frame	O
renderings	O
are	O
relatively	O
simple	O
and	O
fast	O
to	O
calculate	O
,	O
they	O
are	O
often	O
used	O
in	O
cases	O
where	O
a	O
relatively	O
high	O
screen	O
frame	O
rate	O
is	O
needed	O
(	O
for	O
instance	O
,	O
when	O
working	O
with	O
a	O
particularly	O
complex	O
3D	O
model	O
,	O
or	O
in	O
real-time	B-General_Concept
systems	I-General_Concept
that	O
model	O
exterior	O
phenomena	O
)	O
.	O
</s>
<s>
Wire-frame	B-Algorithm
models	I-Algorithm
were	O
also	O
used	O
extensively	O
in	O
video	O
games	O
to	O
represent	O
3D	O
objects	O
during	O
the	O
1980s	O
and	O
early	O
1990s	O
,	O
when	O
"	O
properly	O
"	O
filled	O
3D	O
objects	O
would	O
have	O
been	O
too	O
complex	O
to	O
calculate	O
and	O
draw	O
with	O
the	O
computers	O
of	O
the	O
time	O
.	O
</s>
<s>
Wire-frame	B-Algorithm
models	I-Algorithm
are	O
also	O
used	O
as	O
the	O
input	O
for	O
computer-aided	O
manufacturing	O
(	O
CAM	O
)	O
.	O
</s>
<s>
There	O
are	O
three	O
main	O
types	O
of	O
3D	O
computer-aided	B-Application
design	I-Application
(	O
CAD	B-Application
)	O
models	O
;	O
wire	O
frame	O
is	O
the	O
most	O
abstract	O
and	O
least	O
realistic	O
.	O
</s>
<s>
Appropriate	O
calculations	O
have	O
to	O
be	O
performed	O
to	O
transform	B-Algorithm
the	O
3D	O
coordinates	O
of	O
the	O
vertices	O
into	O
2D	O
screen	O
coordinates	O
.	O
</s>
