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Aladdin-4D Tutorial #11:
Creating arrays with Genie Tools

    Many years ago, for those of you who are too Amiga-young to remember, there
was a 3D program put distributed by a company called MindWare called
PageRender-3D. Though somewhat primitive by today's standards, PageRender had a
few tools that nobody else had. One of these, and my absolute favorite, was the ability
to create what are called "arrays". Arrays are groupings of a cloned object formed in a
specific pattern, such as cubic, spherical, cylindrical, and other 3D possibilities. By
various methods, some too complex to be inviting, you can create arrays in all of
today's Amiga graphic programs. And now, with the superlative list of accessories for
ADSPEC's Aladdin-4D software called "Genie Tools: volume 2" from Shead data
processing, the intuitive magic of array creation is again easy and enjoyable with a tool
called "Point Instancing".

Traditional Aladdin Instancing

    We've already covered the general way that Aladdin addresses instancing an
object in tutorial number nine in Amazing, so we won't bother to go through the whole
process here. Suffice to redefine the instancing process as a way to tell the computer
that a polygon or 3D object that has been selected can be cloned (repeated) any number
of times along a defined path. In A4D's normative instancing process, the selected poly
or object never shows its duplicates on the editing screen, but only appears when
rendered. This is meant to save space when the 3D file is saved, because all that is
stored are the directions and not the polygons. This is fine when you want to animate a
number of objects following a path at the same time, like similar marchers in a large
parade. It does little good, however, when you want to wind a path through the objects
with a flying camera, or have another reason for needing to see the duplicated objects
on the edit screen. Normally, except for wireframe previewing, instanced objects do not
appear until rendered. Shead's Genie Tools ride to the rescue.

Genie Tools

    Let me back up for a second and say a bit about Shead's genie Tools in general.
Ever since Greg Gorby, the author of Aladdin-4D, opened up his program to other
programmer's in version 3.0, there have been a number of folks who have written their
own tools. Usually these tools have addressed processes that A4D was missing, and in
rare cases the new tools have lived up to the high standard Greg Gorby set in the root
program. Genie Tools was an exemplary member of this process from the start. All of
the added tools in volume one, and now in volume two as well, not only added some
new operations, but Mr. Shead seems to have captured the very essence of what
ADSPEC has done in Aladdin itself. Shead's tools have exactly the same look and feel
as the original A4D set, and are just as qualitatively useful and intuitive. All are
accompanied by a wealth of on-line explanatory text, and even tutorials for the
intuitively disadvantaged. Point-Instancing, one of a whole collection of new tools in
volume two, is the tool being referenced in this tutorial. As we continue this series of
A4D tutorials in future issues of Amazing, I'm sure selected Genie Tools will continue
to be a frequent subject of attention.

Point-Instancing

    Unlike their A4D standard counterpart (called simply "instancing"),
point-instanced objects appear on the edit screen for path allocation and whatever other
editing you may want to apply to them (resizing, rotation, deletion of selected
members, etc.). Once objects are point-instanced (meaning duplicated in specific arrays
on the edit screen), it's a fairly simple task to thread a path in between them and fly the
"camera" along it for the animated ride of a lifetime. Given the right recording
equipment, these types of animations rival the hottest stuff seen on the networks. One
of my present projects consists of flying a detailed spaceship into and through a cubic
array of textured revolving spheres.

The Varieties of Point-Instancing

    P-Instancing comes in three flavors in the Genie Tools volume two utility: Cubic,
Spherical, and Cylindrical. Each does exactly what you would expect, arranging any
number of selected polys or objects in the associated array. But there's a lot more
possible then that, because each array type has other controls associated with it as well.
Let's look at each of these three types.

Cubic Arrays

    This would be better understood as a rectangular array, because you can vary the
number of units along any combination of XYZ axis vectors. You could just as easily
produce a planar arrangement as a 3D one by keeping all but one unit number at 1. A
wall of bricks or a tiled floor could be shaped in this manner. Cubic arrays are the
simplest to visualize and understand. Aside from setting the number of the rectangular
elements in the configuration, you can also set the distance the objects maintain from
each other on each separate axis. The scale and rotation of objects can also be set with
each separate axis addressed individually. Scaling and rotation can take place from
either the Attach Point or the object's center.

Cylindrical Arrays

    This gets a bit more complex. In addition to the expected parameters, objects can
be set to rotate by user selected amounts around the Z axis, and there is a special "Align
Theta" button that allows objects to have their faces aligned with the cylindrical shape.

Spherical Arrays

    This is potentially the most complex of the three, though the on-line help files
make operation a virtual snap. There are two "align" toggles here to activate the polys
lining up their faces with the spherical arrangement.

Cautions

    These operations are very computation intensive, and the more cloning that takes
place (the higher number of duplicates chosen on each axis) the more time it takes to
place them in 3D space. I tested these attributes on an Amiga 3000 Tower, and even at
68030 speed, some of the finalizing on the edit screen took over a half hour for larger
arrays. On an Amiga 4000, this time is cut to about a third. I would hate to have to
work with these tools on a stock 2000 unless I had all night to wait for the finished 3D
arrays to be ready to render. One neat animation trick is to set the expected array, and
then with "Deform Mode" on (the way Aladdin 4D generates key frame animations),
snap every object in the array to the center so that they all overlap each other. Once the
animation is rendered, what you witness is the array growing magically out of a single
object. Shead's Genie Tools volume one and two deserves more tutorials, all of which I
hope to provide you with in Amazing time. For now,.. Enjoy! And, oh yes, see you in
ROMulan space.

Aladdin-4D
ADSPEC Programming
1405 N. Ellsworth
Salem, OH 44460
[phone]

Genie Tools: Volumes 1 and 2
Shead Data Processing
4610 Eubank Blvd., NE #1118
Albuquerque, NM  87111
[phone]

Captions to Figures:

Figure 1. A cubic array is one of the most beautiful. Its ordered symmetry appeals to
our sense of balance, and its a snap to produce with genie Tools volume two.

Figure 2. Spherical arrays can be as dense as you'd like. Here, we've taken the same
textured cubic shapes and arranged a small number in a targeted spherical array.

Figure 3. Cylindrical arrays anyone? What a great way to produce a cityscape with
textured buildings, just by varying the P-Instancing in A4D with Genie Tools volume 2.