<s>
High-dynamic-range	B-Device
rendering	I-Device
(	O
HDRR	B-Device
or	O
HDR	B-Device
rendering	I-Device
)	O
,	O
also	O
known	O
as	O
high-dynamic-range	B-General_Concept
lighting	O
,	O
is	O
the	O
rendering	O
of	O
computer	O
graphics	O
scenes	O
by	O
using	O
lighting	O
calculations	O
done	O
in	O
high	B-General_Concept
dynamic	I-General_Concept
range	I-General_Concept
(	O
HDR	O
)	O
.	O
</s>
<s>
The	O
use	O
of	O
high-dynamic-range	B-General_Concept
imaging	O
(	O
HDRI	O
)	O
in	O
computer	O
graphics	O
was	O
introduced	O
by	O
Greg	O
Ward	O
in	O
1985	O
with	O
his	O
open-source	O
Radiance	B-Application
rendering	O
and	O
lighting	O
simulation	O
software	O
which	O
created	O
the	O
first	O
file	O
format	O
to	O
retain	O
a	O
high-dynamic-range	B-General_Concept
image	O
.	O
</s>
<s>
In	O
1990	O
,	O
Nakame	O
,	O
et	O
al.	O
,	O
presented	O
a	O
lighting	O
model	O
for	O
driving	O
simulators	O
that	O
highlighted	O
the	O
need	O
for	O
high-dynamic-range	B-General_Concept
processing	O
in	O
realistic	O
simulations	O
.	O
</s>
<s>
In	O
1997	O
,	O
Paul	O
Debevec	O
presented	O
Recovering	O
high	B-General_Concept
dynamic	I-General_Concept
range	I-General_Concept
radiance	B-Application
maps	O
from	O
photographs	O
at	O
SIGGRAPH	O
,	O
and	O
the	O
following	O
year	O
presented	O
Rendering	O
synthetic	O
objects	O
into	O
real	O
scenes	O
.	O
</s>
<s>
HDRI	O
and	O
HDRL	O
(	O
high-dynamic-range	B-General_Concept
image-based	B-Algorithm
lighting	I-Algorithm
)	O
have	O
,	O
ever	O
since	O
,	O
been	O
used	O
in	O
many	O
situations	O
in	O
3D	O
scenes	O
in	O
which	O
inserting	O
a	O
3D	O
object	O
into	O
a	O
real	O
environment	O
requires	O
the	O
light	O
probe	O
data	O
to	O
provide	O
realistic	O
lighting	O
solutions	O
.	O
</s>
<s>
In	O
gaming	O
applications	O
,	O
Riven	B-Application
:	I-Application
The	I-Application
Sequel	I-Application
to	I-Application
Myst	I-Application
in	O
1997	O
used	O
an	O
HDRI	O
postprocessing	O
shader	O
directly	O
based	O
on	O
Spencer	O
's	O
paper	O
.	O
</s>
<s>
After	O
E3	O
2003	O
,	O
Valve	O
released	O
a	O
demo	O
movie	O
of	O
their	O
Source	B-Application
engine	I-Application
rendering	O
a	O
cityscape	O
in	O
a	O
high	B-General_Concept
dynamic	I-General_Concept
range	I-General_Concept
.	O
</s>
<s>
The	O
term	O
was	O
not	O
commonly	O
used	O
again	O
until	O
E3	O
2004	O
,	O
where	O
it	O
gained	O
much	O
more	O
attention	O
when	O
Epic	O
Games	O
showcased	O
Unreal	B-Operating_System
Engine	I-Operating_System
3	I-Operating_System
and	O
Valve	O
announced	O
Half-Life	B-Application
2	I-Application
:	I-Application
Lost	I-Application
Coast	I-Application
in	O
2005	O
,	O
coupled	O
with	O
open-source	O
engines	O
such	O
as	O
OGRE	B-Language
3D	I-Language
and	O
open-source	O
games	O
like	O
Nexuiz	B-Application
.	O
</s>
<s>
One	O
of	O
the	O
primary	O
advantages	O
of	O
HDR	B-Device
rendering	I-Device
is	O
that	O
details	O
in	O
a	O
scene	O
with	O
a	O
large	O
contrast	O
ratio	O
are	O
preserved	O
.	O
</s>
<s>
These	O
are	O
represented	O
by	O
the	O
hardware	O
as	O
a	O
floating	B-Algorithm
point	I-Algorithm
value	I-Algorithm
of	O
0.0	O
and	O
1.0	O
for	O
pure	O
black	O
and	O
pure	O
white	O
,	O
respectively	O
.	O
</s>
<s>
Another	O
aspect	O
of	O
HDR	B-Device
rendering	I-Device
is	O
the	O
addition	O
of	O
perceptual	O
cues	O
which	O
increase	O
apparent	O
brightness	O
.	O
</s>
<s>
HDR	B-Device
rendering	I-Device
also	O
affects	O
how	O
light	O
is	O
preserved	O
in	O
optical	O
phenomena	O
such	O
as	O
reflections	O
and	O
refractions	O
,	O
as	O
well	O
as	O
transparent	O
materials	O
such	O
as	O
glass	O
.	O
</s>
<s>
However	O
,	O
in	O
HDR	B-Device
rendering	I-Device
,	O
very	O
bright	O
light	O
sources	O
can	O
exceed	O
the	O
1.0	O
brightness	O
to	O
simulate	O
their	O
actual	O
values	O
.	O
</s>
<s>
Although	O
many	O
manufacturers	O
claim	O
very	O
high	O
numbers	O
,	O
plasma	O
displays	O
,	O
LCD	B-Device
displays	I-Device
,	O
and	O
CRT	B-Device
displays	I-Device
can	O
deliver	O
only	O
a	O
fraction	O
of	O
the	O
contrast	O
ratio	O
found	O
in	O
the	O
real	O
world	O
,	O
and	O
these	O
are	O
usually	O
measured	O
under	O
ideal	O
conditions	O
.	O
</s>
<s>
Some	O
increase	O
in	O
dynamic	O
range	O
in	O
LCD	B-Device
monitors	I-Device
can	O
be	O
achieved	O
by	O
automatically	O
reducing	O
the	O
backlight	O
for	O
dark	O
scenes	O
.	O
</s>
<s>
OLED	B-Device
displays	I-Device
have	O
better	O
dynamic	O
range	O
capabilities	O
than	O
LCDs	B-Device
,	O
similar	O
to	O
plasma	O
but	O
with	O
lower	O
power	O
consumption	O
.	O
</s>
<s>
709	O
defines	O
the	O
color	O
space	O
for	O
HDTV	B-Device
,	O
and	O
Rec	O
.	O
</s>
<s>
2020	O
defines	O
a	O
larger	O
but	O
still	O
incomplete	O
color	O
space	O
for	O
ultra-high-definition	B-Device
television	I-Device
.	O
</s>
<s>
Otherwise	O
,	O
HDR	B-Device
rendering	I-Device
systems	O
have	O
to	O
map	O
the	O
full	O
dynamic	O
range	O
of	O
what	O
the	O
eye	O
would	O
see	O
in	O
the	O
rendered	O
situation	O
onto	O
the	O
capabilities	O
of	O
the	O
device	O
.	O
</s>
<s>
This	O
tone	B-Language
mapping	I-Language
is	O
done	O
relative	O
to	O
what	O
the	O
virtual	O
scene	O
camera	O
sees	O
,	O
combined	O
with	O
several	O
full	O
screen	O
effects	O
,	O
e.g.	O
</s>
<s>
Tone	B-Language
mapping	I-Language
and	O
blooming	O
shaders	O
can	O
be	O
used	O
together	O
to	O
help	O
simulate	O
these	O
effects	O
.	O
</s>
<s>
Tone	B-Language
mapping	I-Language
,	O
in	O
the	O
context	O
of	O
graphics	O
rendering	O
,	O
is	O
a	O
technique	O
used	O
to	O
map	O
colors	O
from	O
high	B-General_Concept
dynamic	I-General_Concept
range	I-General_Concept
(	O
in	O
which	O
lighting	O
calculations	O
are	O
performed	O
)	O
to	O
a	O
lower	O
dynamic	O
range	O
that	O
matches	O
the	O
capabilities	O
of	O
the	O
desired	O
display	O
device	O
.	O
</s>
<s>
Various	O
tone	B-Language
mapping	I-Language
operators	I-Language
exist	O
,	O
ranging	O
from	O
simple	O
real-time	O
methods	O
used	O
in	O
computer	O
games	O
to	O
more	O
sophisticated	O
techniques	O
that	O
attempt	O
to	O
imitate	O
the	O
perceptual	O
response	O
of	O
the	O
human	O
visual	O
system	O
.	O
</s>
<s>
Currently	O
HDRR	B-Device
has	O
been	O
prevalent	O
in	O
games	O
,	O
primarily	O
for	O
PCs	B-Device
,	O
Microsoft	O
's	O
Xbox	B-Operating_System
360	I-Operating_System
,	O
and	O
Sony	O
's	O
PlayStation	B-Operating_System
3	I-Operating_System
.	O
</s>
<s>
It	O
has	O
also	O
been	O
simulated	O
on	O
the	O
PlayStation	B-Device
2	I-Device
,	O
GameCube	B-Application
,	O
Xbox	B-Application
and	O
Amiga	B-Device
systems	O
.	O
</s>
<s>
Sproing	O
Interactive	O
Media	O
has	O
announced	O
that	O
their	O
new	O
Athena	O
game	O
engine	O
for	O
the	B-Operating_System
Wii	I-Operating_System
will	O
support	O
HDRR	B-Device
,	O
adding	O
Wii	B-Operating_System
to	O
the	O
list	O
of	O
systems	O
that	O
support	O
it	O
.	O
</s>
<s>
As	O
this	O
includes	O
multiplication	O
and	O
division	O
(	O
which	O
can	O
accumulate	O
rounding	B-Algorithm
errors	I-Algorithm
)	O
,	O
it	O
is	O
useful	O
to	O
have	O
the	O
extended	O
accuracy	O
and	O
range	O
of	O
16	O
bit	O
integer	O
or	O
16	O
bit	O
floating	B-Algorithm
point	I-Algorithm
formats	I-Algorithm
.	O
</s>
<s>
Complex	O
shader	O
effects	O
began	O
their	O
days	O
with	O
the	O
release	O
of	O
Shader	B-Language
Model	I-Language
1.0	O
with	O
DirectX	B-Application
8	I-Application
.	O
</s>
<s>
Shader	B-Language
Model	I-Language
1.0	O
illuminated	O
3D	O
worlds	O
with	O
what	O
is	O
called	O
standard	B-Device
lighting	I-Device
.	O
</s>
<s>
Standard	B-Device
lighting	I-Device
,	O
however	O
,	O
had	O
two	O
problems	O
:	O
</s>
<s>
On	O
December	O
24	O
,	O
2002	O
,	O
Microsoft	O
released	O
a	O
new	O
version	O
of	O
DirectX	B-Application
.	O
</s>
<s>
DirectX	B-Application
9.0	I-Application
introduced	O
Shader	B-Language
Model	I-Language
2.0	I-Language
,	O
which	O
offered	O
one	O
of	O
the	O
necessary	O
components	O
to	O
enable	O
rendering	O
of	O
high-dynamic-range	B-General_Concept
images	O
:	O
lighting	O
precision	O
was	O
not	O
limited	O
to	O
just	O
8-bits	O
.	O
</s>
<s>
One	O
of	O
the	O
first	O
graphics	B-Device
cards	I-Device
to	O
support	O
DirectX	B-Application
9.0	I-Application
natively	O
was	O
ATI	O
's	O
Radeon	B-Device
9700	I-Device
,	O
though	O
the	O
effect	O
was	O
n't	O
programmed	O
into	O
games	O
for	O
years	O
afterwards	O
.	O
</s>
<s>
On	O
August	O
23	O
,	O
2003	O
,	O
Microsoft	O
updated	O
DirectX	B-Application
to	O
DirectX	B-Application
9.0b	I-Application
,	O
which	O
enabled	O
the	O
Pixel	O
Shader	O
2.x	O
(	O
Extended	O
)	O
profile	O
for	O
ATI	O
's	O
Radeon	O
X	O
series	O
and	O
NVIDIA	O
's	O
GeForce	O
FX	O
series	O
of	O
graphics	O
processing	O
units	O
.	O
</s>
<s>
On	O
August	O
9	O
,	O
2004	O
,	O
Microsoft	O
updated	O
DirectX	B-Application
once	O
more	O
to	O
DirectX	B-Application
9.0c	I-Application
.	O
</s>
<s>
This	O
also	O
exposed	O
the	O
Shader	B-Language
Model	I-Language
3.0	I-Language
profile	O
for	O
High-Level	B-Language
Shader	I-Language
Language	I-Language
(	O
HLSL	B-Language
)	O
.	O
</s>
<s>
Shader	B-Language
Model	I-Language
3.0	I-Language
'	O
s	O
lighting	O
precision	O
has	O
a	O
minimum	O
of	O
32	O
bits	O
as	O
opposed	O
to	O
2.0	O
'	O
s	O
8-bit	O
minimum	O
.	O
</s>
<s>
Also	O
all	O
lighting-precision	O
calculations	O
are	O
now	O
floating-point	B-Algorithm
based	O
.	O
</s>
<s>
NVIDIA	O
states	O
that	O
contrast	O
ratios	O
using	O
Shader	B-Language
Model	I-Language
3.0	I-Language
can	O
be	O
as	O
high	O
as	O
65535:1	O
using	O
32-bit	O
lighting	O
precision	O
.	O
</s>
<s>
At	O
first	O
,	O
HDRR	B-Device
was	O
only	O
possible	O
on	O
video	B-Device
cards	I-Device
capable	O
of	O
Shader-Model-3.0	O
effects	O
,	O
but	O
software	O
developers	O
soon	O
added	O
compatibility	O
for	O
Shader	B-Language
Model	I-Language
2.0	I-Language
.	O
</s>
<s>
As	O
a	O
side	O
note	O
,	O
when	O
referred	O
to	O
as	O
Shader	B-Language
Model	I-Language
3.0	I-Language
HDR	O
,	O
HDRR	B-Device
is	O
really	O
done	O
by	O
FP16	O
blending	O
.	O
</s>
<s>
FP16	O
blending	O
is	O
not	O
part	O
of	O
Shader	B-Language
Model	I-Language
3.0	I-Language
,	O
but	O
is	O
supported	O
mostly	O
by	O
cards	O
also	O
capable	O
of	O
Shader	B-Language
Model	I-Language
3.0	I-Language
(	O
exceptions	O
include	O
the	O
GeForce	O
6200	O
series	O
)	O
.	O
</s>
<s>
Shader	B-Language
Model	I-Language
4.0	I-Language
is	O
a	O
feature	O
of	O
DirectX	B-Application
10	I-Application
,	O
which	O
has	O
been	O
released	O
with	O
Windows	O
Vista	O
.	O
</s>
<s>
Shader	B-Language
Model	I-Language
4.0	I-Language
allows	O
128-bit	O
HDR	B-Device
rendering	I-Device
,	O
as	O
opposed	O
to	O
64-bit	O
HDR	O
in	O
Shader	B-Language
Model	I-Language
3.0	I-Language
(	O
although	O
this	O
is	O
theoretically	O
possible	O
under	O
Shader	B-Language
Model	I-Language
3.0	I-Language
)	O
.	O
</s>
<s>
Shader	B-Language
Model	I-Language
5.0	O
is	O
a	O
feature	O
of	O
DirectX	B-Application
11	O
.	O
</s>
<s>
It	O
allows	O
6:1	O
compression	O
of	O
HDR	O
textures	O
without	O
noticeable	O
loss	O
,	O
which	O
is	O
prevalent	O
on	O
previous	O
versions	O
of	O
DirectX	B-Application
HDR	O
texture	O
compression	O
techniques	O
.	O
</s>
<s>
It	O
is	O
possible	O
to	O
develop	O
HDRR	B-Device
through	O
GLSL	B-Language
shader	O
starting	O
from	O
OpenGL	B-Application
1.4	O
onwards	O
.	O
</s>
