<s>
ARB	B-Language
assembly	I-Language
language	I-Language
is	O
a	O
low-level	O
shading	B-Language
language	I-Language
,	O
which	O
can	O
be	O
characterized	O
as	O
an	O
assembly	B-Language
language	I-Language
.	O
</s>
<s>
It	O
was	O
created	O
by	O
the	O
OpenGL	B-Application
Architecture	O
Review	O
Board	O
(	O
ARB	B-Language
)	O
to	O
standardize	O
GPU	B-Architecture
instructions	O
controlling	O
the	O
hardware	O
graphics	B-General_Concept
pipeline	I-General_Concept
.	O
</s>
<s>
Texas	O
Instruments	O
created	O
the	O
first	O
programmable	O
graphics	B-Architecture
processor	I-Architecture
in	O
1985	O
:	O
the	O
TMS34010	B-General_Concept
,	O
which	O
allowed	O
developers	O
to	O
load	O
and	O
execute	O
code	O
on	O
the	O
processor	O
to	O
control	O
pixel	B-Algorithm
output	O
on	O
a	O
video	O
display	O
.	O
</s>
<s>
NVIDIA	O
released	O
its	O
first	O
video	O
card	O
NV1	B-Device
in	O
1995	O
,	O
which	O
supported	O
quadratic	O
texture	O
mapping	O
.	O
</s>
<s>
This	O
was	O
followed	O
by	O
the	O
Riva	B-Device
128	I-Device
(	O
NV3	B-Device
)	O
in	O
1997	O
,	O
providing	O
the	O
first	O
hardware	O
acceleration	O
for	O
Direct3D	B-Application
.	O
</s>
<s>
Various	O
video	O
card	O
vendors	O
released	O
their	O
own	O
accelerated	O
boards	O
,	O
each	O
with	O
their	O
own	O
instruction	O
set	O
for	O
GPU	B-Architecture
operations	O
.	O
</s>
<s>
The	O
OpenGL	B-Application
Architecture	O
Review	O
Board	O
(	O
ARB	B-Language
)	O
was	O
formed	O
in	O
1992	O
,	O
in	O
part	O
to	O
establish	O
standards	O
for	O
the	O
GPU	B-Architecture
industry	O
.	O
</s>
<s>
The	O
ARB	B-Language
and	O
NVIDIA	O
established	O
a	O
number	O
of	O
OpenGL	B-Application
extensions	O
to	O
standardize	O
GPU	B-Architecture
programming	O
:	O
</s>
<s>
These	O
two	O
extensions	O
provided	O
an	O
industry	O
standard	O
for	O
an	O
assembly	B-Language
language	I-Language
that	O
controlled	O
the	O
GPU	B-Architecture
pipeline	O
for	O
3D	O
vertex	O
and	O
interpolated	O
pixel	B-Algorithm
properties	O
,	O
respectively	O
.	O
</s>
<s>
Subsequent	O
high-level	O
shading	B-Language
languages	I-Language
sometimes	O
compile	O
to	O
this	O
ARB	B-Language
standard	O
.	O
</s>
<s>
While	O
3D	O
developers	O
are	O
now	O
more	O
likely	O
to	O
use	O
a	O
C-like	O
,	O
high-level	O
shading	B-Language
language	I-Language
for	O
GPU	B-Architecture
programming	O
,	O
ARB	B-Language
assembly	O
has	O
the	O
advantage	O
of	O
being	O
supported	O
on	O
a	O
wide	O
range	O
of	O
hardware	O
.	O
</s>
<s>
Note	O
however	O
that	O
some	O
features	O
,	O
such	O
as	O
loops	O
and	O
conditionals	O
,	O
are	O
not	O
available	O
in	O
ARB	B-Language
assembly	O
,	O
and	O
using	O
them	O
requires	O
to	O
adopt	O
either	O
the	O
NV_gpu_program4	O
extension	O
,	O
or	O
the	O
GLSL	B-Language
shading	B-Language
language	I-Language
.	O
</s>
<s>
All	O
major	O
graphics	O
card	O
manufacturers	O
have	O
supported	O
ARB	B-Language
assembly	I-Language
language	I-Language
for	O
years	O
,	O
since	O
the	O
NVIDIA	O
Geforce	O
FX	O
series	O
,	O
the	O
AMD	O
R300-based	O
cards	O
(	O
Radeon	B-Device
9500	I-Device
series	O
and	O
higher	O
)	O
,	O
and	O
the	O
Intel	B-Device
GMA	I-Device
900	I-Device
.	O
</s>
<s>
However	O
,	O
standard	O
ARB	B-Language
assembly	I-Language
language	I-Language
is	O
only	O
at	O
the	O
level	O
of	O
Pixel	B-Algorithm
Shader	O
2.0	O
and	O
predates	O
GLSL	B-Language
,	O
so	O
it	O
has	O
very	O
few	O
features	O
.	O
</s>
<s>
While	O
nVidia	O
has	O
made	O
proprietary	O
extensions	O
to	O
ARB	B-Language
assembly	I-Language
languages	I-Language
that	O
combine	O
the	O
fast	O
compile	O
speed	O
of	O
ARB	B-Language
assembly	O
with	O
modern	O
OpenGL	B-Application
3.x	O
features	O
,	O
introduced	O
with	O
the	O
GeForce	O
8	O
Series	O
,	O
most	O
non-nVidia	O
OpenGL	B-Application
implementations	O
do	O
not	O
provide	O
the	O
proprietary	O
nVidia	O
extensions	O
to	O
ARB	B-Language
assembly	I-Language
language	I-Language
and	O
do	O
not	O
offer	O
any	O
other	O
way	O
to	O
access	O
all	O
the	O
shader	O
features	O
directly	O
in	O
assembly	O
,	O
forcing	O
the	O
use	O
of	O
GLSL	B-Language
even	O
for	O
machine	O
generated	O
shaders	O
where	O
assembly	O
would	O
be	O
more	O
appropriate	O
.	O
</s>
<s>
The	O
ARB	B-Language
Vertex	O
Program	O
extension	O
provides	O
APIs	O
to	O
load	O
ARBvp1.0	O
assembly	O
instructions	O
,	O
enable	O
selected	O
programs	O
,	O
and	O
to	O
set	O
various	O
GPU	B-Architecture
parameters	O
.	O
</s>
<s>
The	O
ARB	B-Language
Fragment	O
Program	O
extension	O
provides	O
APIs	O
to	O
load	O
ARBfp1.0	O
assembly	O
instructions	O
,	O
enable	O
selected	O
programs	O
,	O
and	O
to	O
set	O
various	O
GPU	B-Architecture
parameters	O
.	O
</s>
<s>
OpenGL	B-Application
fragments	O
are	O
interpolated	O
pixel	B-Algorithm
definitions	O
.	O
</s>
<s>
The	O
GPU	B-Architecture
's	O
vertex	O
processor	O
calculates	O
all	O
the	O
pixels	B-Algorithm
controlled	O
by	O
a	O
set	O
of	O
vertices	O
,	O
interpolates	O
their	O
position	O
and	O
other	O
properties	O
and	O
passes	O
them	O
onto	O
its	O
fragment	O
process	O
.	O
</s>
<s>
Fragment	O
programs	O
allow	O
developers	O
to	O
modify	O
these	O
pixel	B-Algorithm
properties	O
before	O
they	O
are	O
rendered	O
to	O
a	O
frame	O
buffer	O
for	O
display	O
.	O
</s>
<s>
All	O
ARB	B-Language
assembly	O
variables	O
are	O
float4	O
vectors	O
,	O
which	O
may	O
be	O
addressed	O
by	O
xyzw	O
or	O
rgba	O
suffixes	O
.	O
</s>
<s>
ARB	B-Language
assembly	O
supports	O
the	O
following	O
suffixes	O
for	O
vertex	O
attributes	O
:	O
</s>
<s>
ARB	B-Language
assembly	O
supports	O
the	O
following	O
state	O
matrices	O
:	O
</s>
<s>
ARB	B-Language
assembly	O
supports	O
the	O
following	O
instructions	O
:	O
</s>
<s>
ARB	B-Language
assembly	O
provides	O
no	O
instructions	O
for	O
flow	O
control	O
or	O
branching	O
.	O
</s>
<s>
ARB	B-Language
interfaces	O
provide	O
no	O
compiling	O
step	O
for	O
assembly	B-Language
language	I-Language
.	O
</s>
