AOI - Art of Illusion Introduction
Introduction to interactive creation and manipulation of 3D objects. Art of Illusion is a free
program for creating, rendering and animating 3D objects. It is open
source and allows
scripting using a language that is basically an interpreted version of Java
extended for scripting.
Rather than hash out all the basics here, I recommend that you open
another
browser window and look at some of the basic documentation on
interacting with AOI.
Please open AOI and try to follow along to get a taste for some of the
process of creating and rendering a 3D object. We will discuss some of
these techniques further in class.
Making a coffee mug (modeling)
1. In Front View, Create a cylinder
to be the body of the coffee cup. The base is in the XZ plane with the
height along Y.
Adjust its properties (Edit Object) to have a 1.5 radius in X and Z and
a height of 4. You may have to transform the object to rotate 90
degrees about an axis.
2. Adjust views - the Front and Left views may show the object too
large.
Replace the default value of 100 (at the top of the view) with a
smaller value of 50 or so..
3. It is sometimes helpful to turn on the grid display. (Look for Grids
... under the scene menu)
4. Next to hollow out the interior of
the mug, Copy/Paste the cylinder, scale it to be smaller, then
stretch it to extend beyond the top of the original cylinder. Select
the thinner cylinder as well as the original, under the tools menu,
select "Boolean Modeling" and
use the difference operator to subtract the thin cylinder from the
thicker one.
5. Define the basic shape of the mug
handle, in Front View, using
the Interpolate curve tool to make a curve to . My handle sticks
out to the right.
5.5 Since my handle is to the right, I change the Left View to Right
View.
6. Define a cross-section for the
handle. When swept along the curve of the handle, the handle
itself will be formed.
In the Right/Left View, make a closed
curve using the polygon tool. Double-click the polygon tool and
set it to define a 5 sided approximating
shape. Use the scaling tool to scale the curve so it defines an
appropriate cross section for the mug handle.
Select both the handle curve and the cross-section just created. Under
the Tools menu, pick "extrude".
In the dialog, choose the polygon (closed curve defining the handle
cross-section) as the object to extrude. For the extrude direction,
specify the curve which sketches the profile of the handle and check
the "Orientation follows curve"
checkbox.
7. A new "Extruded Object" forming
the mug handle is created. Move the object into position (move
away the original profile if necessary) Try using the pan and rotate viewport tools
in the perspective window. You should be able to tell if your
handle is stuck correctly on the mug and if it has been hollowed out
properly.
8. Use the "Cube" tool to create a
rectangular slab to act as a tabletop to sit the mug upon.
9. Under the Scene menu, select
Textures and define a New Uniform texture. Name it a desired
color (say "Red")
then adjust the Diffuse color
to be representative of your color's name.
10. Select the mug, then using the
Object menu, Set the Texture of the object to the new uniform
texture you just created.
11. Textures can get quite complicated. AOI provides built in functions
and a unique visual language for defining the details of a texture. The
boxes are functional units which may be connected together. Triangles
pointing out are outputs, those pointing in are inputs. Holding the
mouse down over a triangle will popup information about it, as will
double-clicking on a box.
Here is an example. To create it, use the texture option found uinder
the Scene menu. And create a new texture (procedural 3D).
A grid defines regular locations (a grid) in 3D. Basically, if we are
near enough to one of those locations we are within a white sphere,
otherwise the material is colored light blue.
Render
Render using the raytracer from the view of camera one. Set this up
with the Render ... selection from the Scene menu. Notice how the
renderer shows fine detail that you couldn't see before. Like the
glossy reflection of the mug on the counter top. Feel free to
experiment with adding another light and changing the display mode used
in the other views.
For fun.
You might want to add another mug, and experiment with an image
texture. This texture pattern will give you an idea of what part of the
texture image gets mapped where on your object.
The test pattern, mapped onto another mug. You might experiment with
editing the mappings of an image texture.
