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MegaDisc 06 (1988)(MegaDisc Digital Publishing)(AU)[m][WB].zip
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REVIEWS
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SculptAnimate.rvw
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1988-04-09
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SCULPT ANIMATE 3D -
A REVIEW BY GRAEME WHITTLE
Most Amiga users are by now familiar with the animation of the robot
juggling three mirrored spheres. This animation was one of the first
for the Amiga which employed the powerful graphic technique known as
ray-tracing. This animation was the crea tion of Dr Eric Graham
who went on to write Sculpt 3d and then the animation module for that
program Animate 3d. Combined these programs are argueably the most
powerful graphics software available for any personal computer.
RAY TRACING, WHAT IS IT?
Ray tracing is a relatively new graphics technique, pioneered in the
1960's by nuclear physicist Phillip Mittleman in an attempt to develop
radiation shielding. It was then further developed by Turner Whitted at
the University of North Carolina.
Essentially a ray tracing program follows the paths of light rays
from the viewers position back to the light source, on the way any
"objects" these rays encounter are described in a realistic manner.
The wonder of this technique is that it can describe a variety of
surfaces and textures among them mirroring and refraction. The great
drawback is that this process is computationally intensive and requires
enormous amounts of computing time. This time problem has largely been
overcome with Sculpt 3d as there are a number of tracing modes, you can
also generate partial screen images if you wish.
SCULPT 3D
Sculpt 3d is not copy protected, has a very clear manual and
is reasonably priced. Upon entering the program you are confronted with
three editing screens known as the triview windows, these windows have
various operational gadgets and are resizable. All editing functions are
carried out in the triview. At first I found editing my objects
rather difficult but with practice it soon became a breeze. I now find
that aspects of the editor which I initially found awkward are designed
in such a way that they, with practice, make things easier. Experienced
users of this software will know what I mean. If you are a novice
Sculpt 3d user and are feeling somewhat frustrated with the triview,
persevere - it will all make sense in time.
TRIVIEW WINDOWS
The objects created with the triview editor are based on geodesic
principles, that is they are, without exception composed of triangular
faces. Sound limiting? Well its not, you can in fact describe any three
dimensional form whatever with this program. There are a number of
preset forms such as spheres, cubes, discs, and hemispheres. These can
be used as objects in their own right or they can used as primitives for
more complex structures. The objects are manipulated by selecting vertices
(the corners of the triangles). It is possible to perform a number of
functions on selected vertices without affecting all of the object, you
can colour, smooth, stretch, expand, mirror, reflect, attract or repel
with a magnet, the list goes on and on.
ENVIRONMENTS
Available to the user, as well as all this, are a number environments
in which to place your objects. You can simply place the objects in black
space, this isn't very imaginative but will trace the fastest. Or you
can create a floor, plain or checkered on which to put your creation.
The sky is also user definable, if you wish you can have a green sky
fading into a deep purple at the zenith, this program is that flexible.
In the sculpt 3d environment there is also a camera, a target and
lamps. The camera is the point of view, it can be moved around and it
focuses on the target. You can select from lenses ranging from a
wideangle to a telephoto, or define your own focal length. The lamps are
the all important source of light. They can be moved and you can define
their brightness and colour. You may have as many lamps as you wish, I
have found that one or two lamps is best for most tracings. In fact, if
you are starting out with Sculpt 3d, I suggest that you keep things
simple at first and make more complex objects as you become more
experienced.
TRACING
There are a number of tracing modes available to the user of this
program. Wire frame is the fastest and is the mode I use when I want a
quick look at the position and size of my object. It generates in
seconds. Painting mode is slower, it generates pictures in minutes and
is good for testing the colours of objects. Both wireframe and painted
images can be saved as standard IFF files and loaded into paint programs
if needed. The really powerful modes are snapshot and the ultimate is
photo. Snapshot will give you a full trace in hold and modify (4096
colours) but will not record shadows, it takes from half to a few hours
to generate. Photo mode is the mode you choose just before going to bed,
it will take anything from six to thirty-six hours to complete a full
trace. Mirror and glass take the longest to trace also the more lamps
the more time. Photo mode records all the shadows and every detail
superbly, especially in interlace. I am constantly surprised at the
beauty of the colour and the fine shadings that this mode produces.
Don't be put off by the time factor, after all if you organize things
well you can make use of the Amiga now, even when you are not at home.
You can see the image generating on the screen so if things don't look as
you had hoped you can abort the trace. Also you can set up a batch file
of tracings, I did this when I went away for seven days and when I came
home, there waiting for me were three images with all the slow trace
factors included.
ANIMATION
The animation module for Sculpt 3d is purchased seperately and, be
warned, is useless by itself. Animate 3d combines with Sculpt to make
one new program called Sculpt Animate 3d or SA for short. This not only
adds animation functions to the program, it also upgrades and adds to the
object editor.
There are two types of animation available to the user of SA, they
are, global animation and key frame animation. Global animation is best
used for the movement of predefined objects and key frame animation can be
used for moving and metamorphosing objects. Of the two I found keyframe
to be the easiest to use. You can have up to sixty frames in a movie,
and the best thing is that with a key frame animation you only need to
describe the frames where important changes take place, the rest is
"inbetweened" by the computer. You can preview your animations in wire
frame mode or trace them in any of the modes described previously. The
software then compresses the frames into a remarkably small .anim file.
Animation is a complex business though, especially in three
dimensions and I don't claim to be completely conversant with this aspect
of Sculpt Animate 3d, but I'm learning.
SUMMARY
I have used every 3d graphics program available (in Australia anyway)
for the Amiga and Sculpt Animate simply blows the others off the shelf,
even software costing twice the price.
I do have a few reservations though, sometimes the triview screen
colours become a bit upset, this can be cured by slightly resizing one of
the windows forcing a redraw of the entire screen. A simple undo feature
would be handy, also when I added the Animate module I found that with
some of the features, unless you do things exactly right you can find
yourself staring at a guru.
You can use Sculpt Animate 3d on a 512k machine, but at least a
megabyte is recommended. A hard disk drive is also a good idea for this
program, as some of the files it creates are very large indeed. If you
are interested in raytracing then get to know Sculpt first and then
upgrade to Sculpt Animate, this could save you considerable heartache.
Lastly I am giving tutorials for this program, this could save you even
more heartache, if you are interested see the ARTSCAPE advert (not a
blipvert) elsewhere on this disk.
~~~~~~~~~~~~~~~~~~~~~~~ END OF SCULPTANIMATE.RVW ~~~~~~~~~~~~~~~~~~~~~~~