<s>
Open	B-Application
Inventor	I-Application
,	O
originally	O
IRIS	B-Application
Inventor	I-Application
,	O
is	O
a	O
C++	B-Language
object-oriented	B-Language
retained	O
mode	O
3D	O
graphics	O
toolkit	O
designed	O
by	O
SGI	O
to	O
provide	O
a	O
higher	O
layer	O
of	O
programming	O
for	O
OpenGL	B-Application
.	O
</s>
<s>
Open	B-Application
Inventor	I-Application
exists	O
as	O
both	O
proprietary	B-Application
software	I-Application
and	O
free	B-License
and	I-License
open-source	I-License
software	I-License
,	O
subject	O
to	O
the	O
requirements	O
of	O
the	O
GNU	B-Application
Lesser	I-Application
General	I-Application
Public	I-Application
License	I-Application
(	O
LGPL	B-Application
)	O
,	O
version	O
2.1	O
.	O
</s>
<s>
In	O
the	O
late	O
1980s	O
,	O
Wei	O
Yen	O
and	O
Rikk	O
Carey	O
initiated	O
the	O
IRIS	B-Application
Inventor	I-Application
project	O
to	O
create	O
a	O
toolkit	O
for	O
easier	O
3D	O
graphics	O
application	O
development	O
.	O
</s>
<s>
The	O
project	O
led	O
to	O
the	O
creation	O
of	O
Open	B-Application
Inventor	I-Application
(	O
OI	O
)	O
,	O
which	O
provided	O
a	O
common	O
base	O
layer	O
for	O
3D	O
programming	O
.	O
</s>
<s>
A	O
different	O
approach	O
,	O
OpenGL	B-Library
Performer	I-Library
,	O
prioritized	O
performance	O
optimization	O
but	O
remained	O
proprietary	B-Application
.	O
</s>
<s>
In	O
the	O
mid-1990s	O
,	O
SGI	O
attempted	O
to	O
merge	O
the	O
two	O
systems	O
into	O
Cosmo	O
3D	O
and	O
later	O
OpenGL++	B-Library
,	O
but	O
both	O
projects	O
were	O
ultimately	O
discontinued	O
.	O
</s>
<s>
Open	B-Application
Inventor	I-Application
was	O
licensed	O
to	O
third-party	O
developers	O
,	O
and	O
in	O
August	O
2000	O
,	O
it	O
was	O
released	O
under	O
the	O
LGPL	B-Application
open	O
source	O
license	O
by	O
SGI	O
.	O
</s>
<s>
The	O
Open	B-Application
Inventor	I-Application
API	B-Application
has	O
been	O
widely	O
used	O
in	O
scientific	O
and	O
engineering	O
visualization	O
systems	O
,	O
with	O
Thermo	O
Scientific	O
Open	B-Application
Inventor	I-Application
still	O
under	O
active	O
development	O
for	O
various	O
applications	O
.	O
</s>
<s>
Around	O
19881989	O
,	O
Wei	O
Yen	O
asked	O
Rikk	O
Carey	O
to	O
lead	O
the	O
IRIS	B-Application
Inventor	I-Application
project	O
.	O
</s>
<s>
If	O
3D	O
programming	O
were	O
made	O
easier	O
,	O
through	O
the	O
use	O
of	O
an	O
object	B-Language
oriented	I-Language
API	B-Application
,	O
then	O
more	O
people	O
would	O
create	O
3D	O
applications	O
and	O
SGI	O
would	O
benefit	O
.	O
</s>
<s>
OpenGL	B-Application
(	O
OGL	O
)	O
is	O
a	O
low	O
level	O
application	B-Application
programming	I-Application
interface	I-Application
that	O
takes	O
lists	O
of	O
simple	O
polygons	O
and	O
renders	O
them	O
as	O
quickly	O
as	O
possible	O
.	O
</s>
<s>
Open	B-Application
Inventor	I-Application
(	O
OI	O
)	O
was	O
written	O
to	O
address	O
this	O
issue	O
,	O
and	O
provide	O
a	O
common	O
base	O
layer	O
to	O
start	O
working	O
with	O
.	O
</s>
<s>
The	O
“	O
world	O
”	O
to	O
be	O
drawn	O
was	O
placed	O
in	O
a	O
scene	B-Data_Structure
graph	I-Data_Structure
run	O
by	O
OI	O
,	O
with	O
the	O
system	O
applying	O
occlusion	O
culling	O
on	O
objects	O
in	O
the	O
graph	O
automatically	O
.	O
</s>
<s>
On	O
the	O
downside	O
OI	O
tended	O
to	O
be	O
slower	O
than	O
hand-written	O
code	O
,	O
as	O
3D	O
tasks	O
are	O
notoriously	O
difficult	O
to	O
make	O
perform	O
well	O
without	O
shuffling	O
the	O
data	O
in	O
the	O
scene	B-Data_Structure
graph	I-Data_Structure
by	O
hand	O
.	O
</s>
<s>
Members	O
of	O
the	O
Inventor	O
team	O
left	O
to	O
form	O
their	O
own	O
group	O
,	O
which	O
founded	O
the	O
basis	O
of	O
the	O
OpenGL	B-Library
Performer	I-Library
project	O
.	O
</s>
<s>
Performer	B-Library
was	O
also	O
based	O
on	O
an	O
internal	O
scene	B-Data_Structure
graph	I-Data_Structure
,	O
but	O
was	O
allowed	O
to	O
modify	O
it	O
for	O
better	O
speed	O
as	O
it	O
saw	O
fit	O
,	O
even	O
dropping	O
“	O
less	O
important	O
”	O
objects	O
and	O
polygons	O
in	O
order	O
to	O
maintain	O
guaranteed	O
performance	O
levels	O
.	O
</s>
<s>
Performer	B-Library
also	O
used	O
a	O
number	O
of	O
processes	B-Operating_System
to	O
run	O
tasks	O
in	O
parallel	O
for	O
added	O
performance	O
,	O
allowing	O
it	O
to	O
be	O
run	O
(	O
in	O
one	O
version	O
)	O
on	O
multiple	O
processors	O
.	O
</s>
<s>
Unlike	O
Inventor	O
,	O
Performer	B-Library
remained	O
proprietary	B-Application
so	O
that	O
SGI	O
would	O
have	O
the	O
agility	O
to	O
modify	O
the	O
API	B-Application
as	O
needed	O
to	O
keep	O
in	O
step	O
with	O
the	O
latest	O
hardware	O
enhancements	O
.	O
</s>
<s>
At	O
some	O
point	O
in	O
the	O
mid-1990s	O
it	O
was	O
realized	O
that	O
there	O
was	O
no	O
good	O
reason	O
that	O
the	O
two	O
systems	O
could	O
not	O
be	O
combined	O
,	O
resulting	O
in	O
a	O
single	O
high-level	O
API	B-Application
with	O
both	O
performance	O
and	O
programmability	O
.	O
</s>
<s>
Eventually	O
all	O
of	O
these	O
ideas	O
would	O
come	O
together	O
to	O
create	O
the	O
OpenGL++	B-Library
effort	O
,	O
along	O
with	O
Intel	O
,	O
IBM	O
and	O
DEC	O
.	O
</s>
<s>
Essentially	O
a	O
cleaned	O
up	O
and	O
more	O
“	O
open	O
”	O
version	O
of	O
Cosmo	O
3D	O
,	O
work	O
on	O
Cosmo	O
ended	O
and	O
SGI	O
turned	O
to	O
OpenGL++	B-Library
full-time	O
.	O
</s>
<s>
The	O
OpenGL++	B-Library
effort	O
would	O
drag	O
on	O
and	O
eventually	O
be	O
killed	O
,	O
and	O
SGI	O
then	O
tried	O
again	O
with	O
Microsoft	O
with	O
the	O
similar	O
Fahrenheit	B-Library
project	O
,	O
which	O
also	O
died	O
.	O
</s>
<s>
In	O
1994	O
SGI	O
licensed	O
Open	B-Application
Inventor	I-Application
to	O
two	O
third-party	O
developers	O
,	O
Template	O
Graphics	O
Software	O
(	O
TGS	O
)	O
and	O
Portable	O
Graphics	O
;	O
in	O
1996	O
TGS	O
bought	O
Portable	O
Graphics	O
,	O
making	O
them	O
the	O
sole	O
licensee	O
.	O
</s>
<s>
After	O
many	O
years	O
of	O
being	O
solely	O
available	O
under	O
proprietary	B-Application
licensing	O
from	O
TGS	O
,	O
now	O
FEI	O
,	O
Inventor	O
has	O
been	O
released	O
under	O
the	O
LGPL	B-Application
open	O
source	O
license	O
,	O
in	O
August	O
2000	O
,	O
which	O
is	O
available	O
from	O
SGI	O
.	O
</s>
<s>
At	O
approximately	O
the	O
same	O
time	O
,	O
an	O
API	B-Application
clone	O
library	O
called	O
Coin3D	B-Application
was	O
released	O
by	O
the	O
company	O
SIM	O
(	O
Systems	O
in	O
Motion	O
)	O
.	O
</s>
<s>
The	O
Coin	O
library	O
had	O
been	O
written	O
in	O
a	O
clean	O
room	O
fashion	O
from	O
scratch	O
,	O
sharing	O
no	O
code	O
with	O
the	O
original	O
SGI	O
Inventor	O
library	O
,	O
but	O
implementing	O
the	O
same	O
API	B-Application
for	O
compatibility	O
reasons	O
.	O
</s>
<s>
Kongsberg	O
ended	O
development	O
of	O
Coin3D	B-Application
in	O
2011	O
and	O
released	O
the	O
code	O
under	O
the	O
BSD	O
3-clause	O
license	O
.	O
</s>
<s>
Thermo	O
Scientific	O
Open	B-Application
Inventor	I-Application
is	O
still	O
thriving	O
,	O
under	O
active	O
development	O
and	O
has	O
added	O
numerous	O
improvements	O
to	O
the	O
original	O
Inventor	O
API	B-Application
specifically	O
for	O
medical	B-Application
imaging	I-Application
,	O
medical	B-Algorithm
image	I-Algorithm
computing	I-Algorithm
,	O
3D	O
reflection	O
seismology	O
,	O
and	O
petroleum	O
reservoir	O
modeling	O
.	O
</s>
<s>
The	O
Open	B-Application
Inventor	I-Application
API	B-Application
is	O
still	O
commonly	O
used	O
for	O
a	O
wide	O
range	O
of	O
scientific	O
and	O
engineering	O
visualization	O
systems	O
around	O
the	O
world	O
,	O
having	O
proven	O
itself	O
well	O
designed	O
for	O
effective	O
development	O
of	O
complex	O
3D	O
application	O
software	O
.	O
</s>
<s>
In	O
2004	O
,	O
TGS	O
was	O
acquired	O
by	O
Mercury	B-Application
Computer	I-Application
Systems	I-Application
,	O
and	O
in	O
June	O
2009	O
,	O
the	O
entity	O
became	O
an	O
independent	O
company	O
again	O
called	O
.	O
</s>
