<s>
Ray	B-Algorithm
marching	I-Algorithm
is	O
a	O
class	O
of	O
rendering	O
methods	O
for	O
3D	O
computer	O
graphics	O
where	O
rays	B-Device
are	O
traversed	O
iteratively	O
,	O
effectively	O
dividing	O
each	O
ray	O
into	O
smaller	O
ray	O
segments	O
,	O
sampling	O
some	O
function	O
at	O
each	O
step	O
.	O
</s>
<s>
This	O
function	O
can	O
encode	O
volumetric	O
data	O
for	O
volume	B-Algorithm
ray	I-Algorithm
casting	I-Algorithm
,	O
distance	O
fields	O
for	O
accelerated	O
intersection	O
finding	O
of	O
surfaces	O
,	O
among	O
other	O
information	O
.	O
</s>
<s>
In	O
sphere	O
tracing	O
,	O
or	O
sphere-assisted	O
ray	B-Algorithm
marching	I-Algorithm
an	O
intersection	O
point	O
is	O
approximated	O
between	O
the	O
ray	O
and	O
a	O
surface	O
defined	O
by	O
a	O
signed	O
distance	O
function	O
(	O
SDF	O
)	O
.	O
</s>
<s>
As	O
powerful	O
GPU	B-Architecture
hardware	O
became	O
more	O
widely	O
available	O
,	O
this	O
method	O
was	O
popularized	O
by	O
the	O
demoscene	O
and	O
Inigo	O
Quilez	O
.	O
</s>
<s>
A	O
similar	O
technique	O
to	O
sphere-assisted	O
ray	B-Algorithm
marching	I-Algorithm
,	O
the	O
use	O
of	O
cubes	O
and	O
taxicab	O
distance	O
can	O
be	O
used	O
to	O
render	O
voxel	O
volumes	O
.	O
</s>
<s>
In	O
volumetric	O
ray	B-Algorithm
marching	I-Algorithm
,	O
each	O
ray	O
is	O
traced	O
so	O
that	O
color	O
and/or	O
density	O
can	O
be	O
sampled	O
along	O
the	O
ray	O
and	O
then	O
be	O
combined	O
into	O
a	O
final	O
pixel	O
color	O
.	O
</s>
<s>
When	O
rendering	O
screen	O
space	O
effects	O
,	O
such	O
as	O
screen	O
space	O
reflection	O
(	O
SSR	O
)	O
and	O
screen	O
space	O
shadows	O
,	O
rays	B-Device
are	O
traced	O
using	O
G-buffers	O
,	O
where	O
depth	O
and	O
surface	O
normal	O
data	O
is	O
stored	O
per	O
each	O
2D	O
pixel	O
.	O
</s>
