<s>
id	B-Application
Tech	I-Application
is	O
a	O
series	O
of	O
separate	O
game	O
engines	O
designed	O
and	O
developed	O
by	O
id	O
Software	O
.	O
</s>
<s>
Prior	O
to	O
the	O
presentation	O
of	O
the	O
id	O
Tech	O
5-based	O
game	O
Rage	B-Application
in	O
2011	O
,	O
the	O
engines	O
lacked	O
official	O
designation	O
and	O
as	O
such	O
were	O
simply	O
referred	O
to	O
as	O
the	O
Doom	B-Application
and	O
Quake	B-Application
engines	O
,	O
from	O
the	O
name	O
of	O
the	O
main	O
game	O
series	O
the	O
engines	O
had	O
been	O
developed	O
for	O
.	O
</s>
<s>
"	O
id	B-Application
Tech	I-Application
"	O
has	O
been	O
released	O
as	O
free	B-Application
software	I-Application
under	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
.	O
</s>
<s>
id	B-Application
Tech	I-Application
versions	O
0	O
to	O
3	O
were	O
released	O
under	O
GPL-2.0-or-later	O
.	O
</s>
<s>
id	B-Application
Tech	I-Application
versions	O
3.5	O
to	O
4.5	O
were	O
released	O
under	O
GPL-3.0-or-later	O
.	O
</s>
<s>
id	B-Application
Tech	I-Application
5	I-Application
to	O
7	O
are	O
proprietary	O
,	O
with	O
id	B-Application
Tech	I-Application
7	O
currently	O
being	O
the	O
latest	O
utilized	O
engine	O
.	O
</s>
<s>
However	O
id	B-Application
Tech	I-Application
4	I-Application
had	O
far	O
fewer	O
licensees	O
than	O
the	O
Unreal	B-Operating_System
Engine	I-Operating_System
from	O
Epic	O
Games	O
,	O
and	O
id	O
planned	O
to	O
regain	O
the	O
momentum	O
with	O
id	B-Application
Tech	I-Application
5	I-Application
,	O
until	O
they	O
were	O
bought	O
by	O
ZeniMax	O
Media	O
which	O
intended	O
to	O
keep	O
the	O
id	B-Application
Tech	I-Application
engines	O
exclusively	O
for	O
id	O
's	O
sister	O
studios	O
.	O
</s>
<s>
id	O
Software	O
had	O
developed	O
3D	O
engines	O
for	O
several	O
games	O
before	O
Wolfenstein	B-Application
3D	I-Application
.	O
</s>
<s>
Hovertank	B-Application
3D	I-Application
(	O
1991	O
)	O
used	O
solid-color	O
drawn	O
polygonal	O
walls	O
and	O
scalable	O
sprites	O
.	O
</s>
<s>
The	O
source	O
code	O
was	O
released	O
by	O
Flat	O
Rock	O
Software	O
in	O
June	O
2014	O
under	O
GPL-2.0-or-later	O
.	O
</s>
<s>
Catacomb	B-Application
3-D	I-Application
(	O
1991	O
)	O
added	O
texture	O
mapping	O
to	O
the	O
walls	O
.	O
</s>
<s>
The	O
source	O
code	O
was	O
released	O
by	O
Flat	O
Rock	O
Software	O
in	O
June	O
2014	O
under	O
GPL-2.0-or-later	O
.	O
</s>
<s>
Wolfenstein	B-Application
3D	I-Application
(	O
1992	O
)	O
increased	O
the	O
color	O
palette	O
from	O
16-color	O
EGA	B-Device
to	O
256-color	O
VGA	B-Protocol
and	O
also	O
adopted	O
raycasting	B-Algorithm
.	O
</s>
<s>
The	O
source	O
code	O
to	O
Wolfenstein	B-Application
3D	I-Application
,	O
along	O
with	O
its	O
prequel	O
Spear	B-Application
of	I-Application
Destiny	I-Application
,	O
was	O
released	O
on	O
the	O
21st	O
of	O
July	O
1995	O
under	O
a	O
proprietary	O
license	O
,	O
and	O
then	O
later	O
under	O
GPL-2.0-or-later	O
.	O
</s>
<s>
ShadowCaster	B-Application
(	O
1993	O
)	O
was	O
built	O
upon	O
the	O
Wolfenstein	B-Application
3D	I-Application
engine	O
and	O
was	O
licensed	O
out	O
to	O
Raven	O
Software	O
.	O
</s>
<s>
This	O
Raven	O
engine	O
was	O
later	O
also	O
used	O
by	O
CyClones	B-Device
and	O
In	B-Application
Pursuit	I-Application
of	I-Application
Greed	I-Application
.	O
</s>
<s>
Rise	B-Application
of	I-Application
the	I-Application
Triad	I-Application
uses	O
an	O
enhanced	O
engine	O
of	O
Wolfenstein	B-Application
3D	I-Application
and	O
was	O
meant	O
to	O
serve	O
as	O
the	O
sequel	O
to	O
it	O
.	O
</s>
<s>
The	O
source	O
code	O
was	O
released	O
on	O
the	O
20th	O
of	O
December	O
2002	O
under	O
GPL-2.0-or-later	O
.	O
</s>
<s>
Other	O
games	O
using	O
this	O
engine	O
are	O
:	O
Blake	B-Application
Stone	I-Application
:	I-Application
Aliens	I-Application
of	I-Application
Gold	I-Application
,	O
Blake	B-Application
Stone	I-Application
:	I-Application
Planet	I-Application
Strike	I-Application
,	O
Corridor	B-Application
7	I-Application
:	I-Application
Alien	I-Application
Invasion	I-Application
,	O
Operation	B-Application
Body	I-Application
Count	I-Application
,	O
and	O
Rise	B-Application
of	I-Application
the	I-Application
Triad	I-Application
.	O
</s>
<s>
Originally	O
known	O
as	O
the	O
"	O
Doom	B-Application
engine	O
"	O
,	O
this	O
engine	O
powers	O
the	O
id	O
Software	O
games	O
Doom	B-Application
(	O
1993	O
)	O
and	O
Doom	B-Application
II	I-Application
:	I-Application
Hell	I-Application
on	I-Application
Earth	I-Application
(	O
1994	O
)	O
.	O
</s>
<s>
Initially	O
developed	O
on	O
NeXT	O
computers	O
,	O
it	O
was	O
ported	O
to	O
MS-DOS	B-Application
for	O
Doom	B-Application
's	O
release	O
and	O
was	O
later	O
ported	O
to	O
several	O
game	O
consoles	O
and	O
operating	B-General_Concept
systems	I-General_Concept
.	O
</s>
<s>
The	O
source	O
code	O
was	O
released	O
on	O
the	O
23rd	O
of	O
December	O
1997	O
under	O
a	O
proprietary	O
license	O
,	O
and	O
then	O
later	O
on	O
the	O
3rd	O
of	O
October	O
1999	O
under	O
GPL-2.0-or-later	O
.	O
</s>
<s>
Their	O
sources	O
were	O
released	O
on	O
the	O
4th	O
of	O
September	O
2008	O
under	O
GPL-2.0-only	O
.	O
</s>
<s>
Other	O
games	O
using	O
this	O
engine	O
include	O
Strife	B-Application
:	I-Application
Quest	I-Application
for	I-Application
the	I-Application
Sigil	I-Application
and	O
Chex	B-Application
Quest	I-Application
.	O
</s>
<s>
Originally	O
known	O
as	O
"	O
Quake	B-Application
engine	O
"	O
,	O
it	O
was	O
originally	O
written	O
to	O
power	O
1996	O
's	O
Quake	B-Application
.	O
</s>
<s>
It	O
featured	O
true	O
3D	O
real-time	B-General_Concept
rendering	I-General_Concept
and	O
is	O
the	O
first	O
id	B-Application
Tech	I-Application
engine	O
to	O
use	O
the	O
client	B-Operating_System
–	I-Operating_System
server	I-Operating_System
model	I-Operating_System
.	O
</s>
<s>
The	O
source	O
code	O
was	O
released	O
on	O
the	O
21st	O
of	O
December	O
1999	O
under	O
GPL-2.0-or-later	O
.	O
</s>
<s>
The	O
Quake	B-Application
engine	O
was	O
updated	O
with	O
a	O
new	O
executable	O
titled	O
QuakeWorld	O
that	O
contained	O
code	O
to	O
enhance	O
the	O
networking	O
capabilities	O
of	O
Quake	B-Application
in	O
response	O
to	O
the	O
demand	O
for	O
across-internet	O
network	O
games	O
that	O
arose	O
as	O
a	O
result	O
of	O
Quakes	B-Application
usage	O
of	O
UDP	B-Protocol
for	O
networking	O
.	O
</s>
<s>
id	B-Application
Tech	I-Application
2	O
was	O
later	O
updated	O
for	O
the	O
release	O
of	O
Quake	B-Application
II	I-Application
in	O
1997	O
,	O
with	O
enhancements	O
such	O
as	O
colored	O
lighting	O
and	O
a	O
new	O
MD2	O
model	O
format	O
.	O
</s>
<s>
id	B-Application
Tech	I-Application
2.5	O
is	O
the	O
last	O
to	O
include	O
a	O
software	O
renderer	O
.	O
</s>
<s>
The	O
source	O
code	O
was	O
released	O
on	O
the	O
22nd	O
of	O
December	O
2001	O
under	O
GPL-2.0-or-later	O
.	O
</s>
<s>
Originally	O
known	O
as	O
the	O
"	O
Quake	B-Application
III	I-Application
Arena	I-Application
engine	O
"	O
,	O
it	O
was	O
used	O
to	O
power	O
id	O
Software	O
's	O
Quake	B-Application
III	I-Application
Arena	I-Application
in	O
1999	O
.	O
</s>
<s>
The	O
Quake	B-Application
III	I-Application
Arena	I-Application
engine	O
was	O
updated	O
to	O
patch	O
1.26	O
and	O
later	O
versions	O
are	O
called	O
"	O
Quake	B-Application
III	I-Application
Team	O
Arena	O
engine	O
"	O
with	O
a	O
new	O
MD4	O
skeletal	O
model	O
format	O
and	O
huge	O
outdoor	O
areas	O
.	O
</s>
<s>
id	B-Application
Tech	I-Application
3	I-Application
is	O
the	O
first	O
in	O
this	O
series	O
to	O
require	O
an	O
OpenGL-compliant	O
graphics	B-Architecture
accelerator	I-Architecture
to	O
run	O
.	O
</s>
<s>
The	O
source	O
code	O
was	O
released	O
on	O
the	O
19th	O
of	O
August	O
2005	O
under	O
GPL-2.0-or-later	O
.	O
</s>
<s>
id	B-Application
Tech	I-Application
3	I-Application
was	O
updated	O
with	O
the	O
2001	O
release	O
of	O
Return	B-Application
To	I-Application
Castle	I-Application
Wolfenstein	I-Application
which	O
included	O
a	O
single-player	O
scripting	O
system	O
,	O
and	O
was	O
eventually	O
used	O
to	O
power	O
the	O
first	O
Call	B-Application
of	I-Application
Duty	I-Application
title	O
in	O
2003	O
,	O
ultimately	O
spawning	O
the	O
IW	B-Application
engine	I-Application
.	O
</s>
<s>
It	O
was	O
also	O
used	O
for	O
Wolfenstein	B-Application
:	I-Application
Enemy	I-Application
Territory	I-Application
.	O
</s>
<s>
The	O
source	O
code	O
was	O
released	O
on	O
the	O
12th	O
of	O
August	O
2010	O
under	O
GPL-3.0-or-later	O
.	O
</s>
<s>
Commonly	O
known	O
as	O
the	O
"	O
Doom	B-Application
3	I-Application
engine	I-Application
"	O
which	O
was	O
used	O
to	O
power	O
Doom	B-Application
3	I-Application
as	O
it	O
released	O
in	O
2004	O
,	O
id	B-Application
Tech	I-Application
4	I-Application
began	O
as	O
an	O
enhancement	O
to	O
id	B-Application
Tech	I-Application
3	I-Application
.	O
</s>
<s>
The	O
decision	O
to	O
switch	O
from	O
C	B-Language
to	O
the	O
C++	B-Language
programming	I-Language
language	I-Language
necessitated	O
a	O
restructuring	O
and	O
rewrite	O
of	O
the	O
rest	O
of	O
the	O
engine	O
;	O
today	O
,	O
while	O
id	B-Application
Tech	I-Application
4	I-Application
contains	O
code	O
from	O
id	B-Application
Tech	I-Application
3	I-Application
,	O
much	O
of	O
it	O
has	O
been	O
rewritten	O
.	O
</s>
<s>
The	O
source	O
code	O
was	O
released	O
on	O
the	O
22nd	O
of	O
November	O
2011	O
under	O
GPL-3.0-or-later	O
.	O
</s>
<s>
Other	O
games	O
using	O
this	O
engine	O
are	O
:	O
Raven	O
Software	O
's	O
Quake	B-Application
4	I-Application
(	O
2005	O
)	O
and	O
Wolfenstein	B-Application
(	O
2009	O
)	O
,	O
Human	O
Head	O
Studios	O
 '	O
Prey	B-Application
(	O
2006	O
)	O
,	O
Splash	O
Damage	O
's	O
Enemy	B-Application
Territory	I-Application
:	I-Application
Quake	I-Application
Wars	I-Application
(	O
2007	O
)	O
and	O
Brink	B-Application
(	O
2011	O
)	O
.	O
</s>
<s>
id	B-Application
Tech	I-Application
4	I-Application
was	O
updated	O
with	O
the	O
2012	O
release	O
of	O
Doom	B-Application
3	I-Application
:	I-Application
BFG	I-Application
Edition	I-Application
with	O
some	O
features	O
from	O
id	B-Application
Tech	I-Application
5	I-Application
.	O
</s>
<s>
The	O
source	O
code	O
was	O
released	O
on	O
the	O
26th	O
of	O
November	O
2012	O
under	O
GPL-3.0-or-later	O
.	O
</s>
<s>
Used	O
for	O
id	O
Software	O
's	O
Rage	B-Application
,	O
the	O
engine	O
is	O
based	O
on	O
the	O
file	O
system	O
frameworks	O
.	O
</s>
<s>
Some	O
technologies	O
included	O
are	O
the	O
GUI	O
system	O
from	O
id	B-Application
Tech	I-Application
4	I-Application
,	O
including	O
a	O
new	O
renderer	O
,	O
MegaTexture	O
2.0	O
technology	O
,	O
soft	O
shadows	O
and	O
more	O
.	O
</s>
<s>
The	O
engine	O
has	O
since	O
been	O
used	O
to	O
power	O
MachineGames	O
 '	O
first	O
two	O
Wolfenstein	B-Application
titles	O
;	O
The	O
New	O
Order	O
in	O
2014	O
with	O
its	O
standalone	O
expansion	O
The	B-Application
Old	I-Application
Blood	I-Application
,	O
which	O
released	O
in	O
2015	O
.	O
</s>
<s>
It	O
was	O
also	O
used	O
for	O
Tango	O
Gameworks	O
 '	O
The	B-Application
Evil	I-Application
Within	I-Application
(	O
2014	O
)	O
.	O
</s>
<s>
Used	O
for	O
Doom	B-Application
released	O
on	O
May	O
13	O
,	O
2016	O
.	O
</s>
<s>
While	O
the	O
engine	O
uses	O
some	O
of	O
the	O
features	O
from	O
id	B-Application
Tech	I-Application
5	I-Application
,	O
id	O
has	O
also	O
added	O
support	O
for	O
Vulkan	B-Application
rendering	O
.	O
</s>
<s>
Development	O
of	O
the	O
renderer	O
is	O
led	O
by	O
Tiago	O
Sousa	O
,	O
who	O
had	O
previously	O
worked	O
on	O
CryEngine	B-Application
,	O
following	O
previous	O
technical	O
director	O
John	O
Carmack	O
's	O
resignation	O
in	O
2013	O
.	O
id	B-Application
Tech	I-Application
6	O
was	O
also	O
used	O
in	O
Wolfenstein	B-Application
II	I-Application
:	I-Application
The	I-Application
New	I-Application
Colossus	I-Application
(	O
2017	O
)	O
,	O
and	O
Wolfenstein	B-Application
:	I-Application
Youngblood	I-Application
(	O
2019	O
)	O
again	O
by	O
MachineGames	O
.	O
</s>
<s>
It	O
was	O
not	O
used	O
for	O
Quake	B-Application
Champions	I-Application
however	O
,	O
which	O
combined	O
id	B-Application
Tech	I-Application
features	O
with	O
the	O
Saber3D	O
Engine	O
.	O
</s>
<s>
At	O
QuakeCon	O
2018	O
,	O
id	O
Software	O
announced	O
the	O
release	O
of	O
a	O
new	O
game	O
in	O
the	O
Doom	B-Application
franchise	O
called	O
Doom	B-Application
Eternal	I-Application
.	O
</s>
<s>
Powered	O
by	O
the	O
id	B-Application
Tech	I-Application
7	O
engine	O
,	O
Doom	B-Application
Eternal	I-Application
was	O
released	O
on	O
March	O
20	O
,	O
2020	O
.	O
</s>
<s>
The	O
new	O
engine	O
is	O
capable	O
of	O
delivering	O
an	O
increase	O
in	O
geometric	O
detail	O
without	O
drops	O
in	O
frame-rate	O
vs.	O
id	B-Application
Tech	I-Application
6	O
.	O
</s>
<s>
On	O
PC	O
,	O
id	B-Application
Tech	I-Application
7	O
supports	O
Vulkan	B-Application
rendering	O
only	O
.	O
</s>
