<s>
The	O
C4	B-Operating_System
Engine	I-Operating_System
is	O
a	O
proprietary	O
computer	O
game	O
engine	O
developed	O
by	O
Terathon	O
Software	O
that	O
is	O
used	O
to	O
create	O
3D	O
games	O
and	O
other	O
types	O
of	O
interactive	O
virtual	O
simulations	O
for	O
PlayStation	B-Device
5	I-Device
,	O
PlayStation	B-Operating_System
4	I-Operating_System
,	O
PlayStation	B-Operating_System
3	I-Operating_System
,	O
Windows	B-Application
(	O
XP	B-Application
and	O
later	O
)	O
,	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
(	O
versions	O
10.9	B-Operating_System
and	O
later	O
)	O
,	O
Linux	B-Application
,	O
and	O
iOS	B-Application
.	O
</s>
<s>
Development	O
of	O
the	O
C4	B-Operating_System
Engine	I-Operating_System
is	O
led	O
by	O
computer	O
graphics	O
author	O
Eric	O
Lengyel	O
,	O
who	O
is	O
also	O
the	O
founder	O
of	O
Terathon	O
Software	O
.	O
</s>
<s>
Due	O
to	O
changing	O
market	O
conditions	O
,	O
the	O
C4	B-Operating_System
Engine	I-Operating_System
was	O
retired	O
in	O
2015	O
,	O
but	O
an	O
announcement	O
has	O
been	O
made	O
that	O
it	O
is	O
returning	O
in	O
2021	O
.	O
</s>
<s>
C4	B-Operating_System
Engine	I-Operating_System
version	O
7.0	O
is	O
released	O
on	O
22nd	O
of	O
March	O
2023	O
.	O
</s>
<s>
The	O
architecture	O
of	O
the	O
C4	B-Operating_System
Engine	I-Operating_System
is	O
that	O
of	O
a	O
layered	O
collection	O
of	O
software	O
components	O
,	O
in	O
which	O
the	O
lowest	O
layers	O
interact	O
with	O
the	O
computer	O
hardware	O
and	O
operating	O
system	O
,	O
and	O
the	O
higher	O
layers	O
provide	O
platform-independent	B-Operating_System
services	O
to	O
the	O
game	O
code	O
.	O
</s>
<s>
The	O
C4	B-Operating_System
Engine	I-Operating_System
is	O
based	O
on	O
the	O
OpenGL	B-Application
library	O
on	O
Windows	B-Application
,	O
Mac	O
,	O
Linux	B-Application
,	O
and	O
iOS	B-Application
platforms	O
,	O
and	O
it	O
uses	O
a	O
one-pass-per-light	O
forward	O
rendering	O
model	O
.	O
</s>
<s>
Material	O
attributes	O
can	O
be	O
used	O
to	O
produce	O
effects	O
such	O
as	O
normal	B-Application
mapping	I-Application
,	O
parallax	O
mapping	O
,	O
horizon	O
mapping	O
,	O
and	O
bumpy	O
reflections	O
or	O
refractions	O
.	O
</s>
<s>
The	O
terrain	O
capabilities	O
of	O
the	O
C4	B-Operating_System
Engine	I-Operating_System
are	O
based	O
on	O
a	O
voxel	O
technology	O
,	O
allowing	O
full	O
3D	O
sculpting	O
to	O
produce	O
features	O
such	O
as	O
overhangs	O
,	O
arches	O
,	O
and	O
truly	O
vertical	O
cliffs	O
that	O
would	O
not	O
be	O
possible	O
under	O
a	O
conventional	O
height-based	O
terrain	O
system	O
.	O
</s>
<s>
Triangle	O
meshes	O
are	O
generated	O
from	O
voxel	O
data	O
using	O
the	O
Marching	B-Algorithm
cubes	I-Algorithm
algorithm	I-Algorithm
,	O
and	O
seamless	O
multiresolution	O
level	O
of	O
detail	O
is	O
made	O
possible	O
by	O
using	O
the	O
Transvoxel	O
algorithm	O
to	O
stitch	O
together	O
regions	O
of	O
differing	O
resolutions	O
.	O
</s>
<s>
The	O
C4	B-Operating_System
Engine	I-Operating_System
can	O
play	O
sounds	O
stored	O
in	O
the	O
WAV	O
format	O
using	O
16-bit	O
mono	O
or	O
stereo	O
sampling	O
,	O
and	O
audio	O
data	O
can	O
be	O
played	O
from	O
memory	O
or	O
streamed	O
from	O
disk	O
.	O
</s>
<s>
Multiplayer	O
gameplay	O
in	O
C4	O
is	O
supported	O
by	O
a	O
two-layer	O
messaging	O
system	O
that	O
uses	O
the	O
User	B-Protocol
Datagram	I-Protocol
Protocol	I-Protocol
to	O
communicate	O
among	O
different	O
computers	O
connected	O
to	O
a	O
game	O
.	O
</s>
<s>
The	O
C4	B-Operating_System
Engine	I-Operating_System
has	O
a	O
native	O
physics	O
engine	O
which	O
can	O
be	O
used	O
or	O
allows	O
the	O
option	O
for	O
implementing	O
a	O
3rd	O
party	O
solution	O
instead	O
.	O
</s>
<s>
The	O
C4	B-Operating_System
Engine	I-Operating_System
ships	O
with	O
basic	O
game	O
development	O
tools	O
required	O
to	O
make	O
a	O
modern	O
game	O
.	O
</s>
<s>
Many	O
tools	O
make	O
use	O
of	O
the	O
comprehensive	O
graphical	B-Application
user	I-Application
interface	I-Application
system	O
provided	O
by	O
the	O
engine	O
so	O
that	O
a	O
consistent	O
interface	O
is	O
presented	O
to	O
the	O
user	O
across	O
multiple	B-Operating_System
platforms	I-Operating_System
.	O
</s>
<s>
The	O
World	O
Editor	O
tool	O
is	O
a	O
3D	O
content	O
creation	O
application	O
that	O
is	O
typically	O
used	O
to	O
create	O
game	O
environments	O
for	O
use	O
with	O
the	O
C4	B-Operating_System
Engine	I-Operating_System
.	O
</s>
<s>
This	O
enables	O
the	O
use	O
of	O
content	O
from	O
a	O
large	O
number	O
of	O
digital	O
content	O
creation	O
programs	O
such	O
as	O
Autodesk	B-Language
Maya	I-Language
or	O
3D	B-Language
Studio	I-Language
Max	I-Language
.	O
</s>
<s>
The	O
C4	B-Operating_System
Engine	I-Operating_System
is	O
licensed	O
for	O
$100	O
per	O
person	O
,	O
and	O
this	O
includes	O
all	O
future	O
updates	O
at	O
no	O
additional	O
cost	O
.	O
</s>
<s>
The	O
C4	B-Operating_System
Engine	I-Operating_System
has	O
been	O
licensed	O
by	O
many	O
universities	O
in	O
connection	O
with	O
games-oriented	O
software	O
engineering	O
curricula	O
or	O
for	O
special	O
research	O
projects	O
.	O
</s>
<s>
Students	O
in	O
some	O
of	O
these	O
programs	O
are	O
required	O
to	O
create	O
their	O
own	O
games	O
as	O
part	O
of	O
a	O
course	O
using	O
the	O
C4	B-Operating_System
Engine	I-Operating_System
,	O
and	O
many	O
of	O
these	O
projects	O
have	O
gone	O
on	O
to	O
be	O
entered	O
in	O
the	O
Independent	O
Games	O
Festival	O
student	O
competition	O
.	O
</s>
<s>
One	O
particular	O
university	O
research	O
project	O
involved	O
the	O
TactaVest	O
technology	O
developed	O
at	O
WPI	O
,	O
and	O
their	O
use	O
of	O
the	O
C4	B-Operating_System
Engine	I-Operating_System
was	O
featured	O
in	O
the	O
Discovery	O
Channel	O
Canada	O
television	O
show	O
Daily	O
Planet	O
airing	O
on	O
May	O
26	O
,	O
2006	O
.	O
</s>
<s>
Games	O
that	O
use	O
the	O
C4	B-Operating_System
Engine	I-Operating_System
include	O
:	O
</s>
