<s>
Nightfall	B-Application
is	O
an	O
American	O
computer	O
game	O
released	O
in	O
1998	O
by	O
Altor	O
Systems	O
,	O
Inc	O
.	O
</s>
<s>
Although	O
claimed	O
to	O
be	O
the	O
first	O
real-time	B-General_Concept
3D	O
first	O
person	O
adventure	O
game	O
,	O
there	O
are	O
earlier	O
examples	O
of	O
3D	O
first	O
person	O
adventure	O
games	O
,	O
however	O
,	O
such	O
as	O
Total	B-Application
Eclipse	I-Application
,	O
released	O
in	O
1988	O
.	O
</s>
<s>
Essentially	O
,	O
the	O
gameplay	O
is	O
a	O
combination	O
of	O
3D	O
first-person	O
shooters	O
such	O
as	O
Doom	B-Application
,	O
the	O
gameplay	O
found	O
in	O
Myst	B-Application
,	O
with	O
some	O
additional	O
elements	O
.	O
</s>
<s>
The	O
gameplay	O
hand	O
based	O
interface	O
is	O
detailed	O
in	O
a	O
Game	O
Developers	O
Conference	O
paper	O
that	O
compares	O
Unreal	B-Application
,	O
Quake	B-Application
,	O
Trespasser	B-Application
,	O
Tomb	B-Application
Raider	I-Application
,	O
Myst	B-Application
,	O
and	O
Nightfall	B-Application
styles	O
of	O
interaction	O
.	O
</s>
<s>
This	O
solves	O
a	O
problem	O
with	O
Myst	B-Application
's	O
gameplay	O
–	O
that	O
some	O
puzzles	O
cannot	O
be	O
solved	O
,	O
so	O
gameplay	O
cannot	O
proceed	O
as	O
the	O
player	O
is	O
"	O
stuck	O
"	O
.	O
</s>
<s>
In	O
the	O
case	O
of	O
Myst	B-Application
,	O
a	O
workaround	O
is	O
that	O
the	O
player	O
obtains	O
the	O
solution	O
from	O
elsewhere	O
–	O
e.g.	O
</s>
<s>
While	O
playing	O
Nightfall	B-Application
,	O
alternative	O
solutions	O
can	O
be	O
found	O
within	O
the	O
game	O
itself	O
.	O
</s>
<s>
The	O
map	O
dynamically	O
refreshes	O
to	O
show	O
the	O
areas	O
the	O
user	O
has	O
visited	O
or	O
can	O
see	O
,	O
much	O
as	O
games	O
like	O
Marathon	B-Application
do	O
.	O
</s>
<s>
These	O
include	O
"	O
Volumetric	O
real-time	B-General_Concept
light	O
model	O
"	O
,	O
"	O
Dynamic	O
depth	O
cued	O
colored	O
fog	O
and	O
dust	O
 '	O
,	O
'	O
Physics	O
model	O
for	O
collision	O
,	O
gravity	O
,	O
and	O
object	O
stacking	O
"	O
,	O
and	O
a	O
'	O
VR	O
hand	O
to	O
select	O
and	O
pick	O
up	O
objects	O
during	O
game	O
play	O
or	O
editing	O
 '	O
.	O
</s>
<s>
Mac	O
Gamers	O
Ledge	O
gave	O
it	O
5/5	O
and	O
states	O
that	O
'	O
Nightfall	B-Application
has	O
breathed	O
new	O
life	O
into	O
the	O
adventure	O
genre	O
by	O
truly	O
allowing	O
you	O
to	O
explore	O
a	O
vast	O
and	O
interesting	O
new	O
world	O
.	O
</s>
<s>
On	O
a	O
technical	O
note	O
,	O
the	O
reviewer	O
states	O
'	O
Nightfall	B-Application
was	O
designed	O
using	O
a	O
first-person	O
engine	O
,	O
and	O
it	O
was	O
designed	O
from	O
scratch	O
,	O
a	O
feat	O
involving	O
writing	O
two	O
million	O
lines	O
of	O
code	O
,	O
which	O
should	O
get	O
an	O
A	O
even	O
though	O
we	O
do	O
n't	O
give	O
scores	O
for	O
programming	O
!	O
</s>
<s>
The	O
game	O
is	O
only	O
compatible	O
with	O
Apple	O
computers	O
which	O
use	O
the	O
Mac	B-Application
OS	I-Application
running	O
on	O
PowerPC	O
processors	O
,	O
and	O
it	O
was	O
not	O
ported	O
to	O
other	O
operating	O
systems	O
.	O
</s>
<s>
While	O
not	O
directly	O
related	O
,	O
other	O
3D	O
adventures	O
such	O
as	O
realMyst	B-Application
followed	O
,	O
and	O
some	O
of	O
the	O
gameplay	O
mechanics	O
were	O
similar	O
to	O
those	O
in	O
Nightfall	B-Application
.	O
</s>
<s>
A	O
review	O
of	O
realMyst	B-Application
compared	O
its	O
freedom	O
of	O
motion	O
to	O
'	O
Altor	O
Systems	O
with	O
their	O
ahead-of-its-time	O
game	O
,	O
Nightfall	B-Application
 '	O
.	O
</s>
