Datasheet

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CHAPTER 1
CHAPTER 2
CHAPTER 3
CHAPTER 4
CHAPTER 5
CHAPTER 6
CHAPTER 7
CHAPTER 8
CHAPTER 9
CHAPTER 10
CHAPTER 11
CHAPTER 12
CHAPTER 13
CHAPTER 14
APPENDICES
INDEX
■ HOLLOW
Remember that the Hollow feature works along
the path of an extruded 2D shape. This means
that for linearly extruded objects a hollow will
appear along the z-axis (much like with path
cuts), but for radially extruded objects Hollow will
hollow out a rounded shape. While most hollow
shapes match the extruded 2D shape, you can
also hollow out a circle, a square, or a triangle.
Like path cuts, Hollow can be used to help
save prims. For example, if you want to create
a room with four walls, you might use one box
per wall, totaling four boxes. But the savvy
builder could use one large hollowed box (Figure
3.3). That’s four wall surfaces for the price of
one! If you need to add a door, simply play with
the cut values. (Unfortunately, the door will have
to appear in the corner of the room since that’s
where box path cuts start.)
■ TWIST
Twists are the weapon of choice for many organic builds, such as trees and fl owers. Like hollows,
twists occur along the path of extrusion, so they behave quite differently for linearly extruded objects
and radially extruded objects. Linearly extruded objects are fairly straightforward; for example,
twisting a box can give it a cruller shape, and if tapered to a point it could make a convincing drill or
unicorn horn.
Radially extruded objects, on the
other hand, cause one of the ends of the
extruded loop to break continuity and fl ip
around. If you enter a twist of 180 degrees
on the beginning part of a tube it causes
a half-twist, where it once again meshes
up seamlessly with the end. This creates
the famous shape known as a Möbius strip
(Figure 3.4). Performing the same trick on a
torus makes a pretty, lily-like fl ower shape.
Many prims become distorted when
twisting. Here is a cool trick that takes
advantage of this. As you know, there is
a 10-meter limitation on prim sizes. But
say you wanted a cylinder larger than 10
meters—perhaps for the foundation of a
castle or for a landing pad for a spaceship.
Figure 3.3: A room using four prims (left), and
the same room using one prim (right)
WARNING
WARNIN
G
Using a hollow prim as a room is a great way to save prims, but it has one drawback: When you
try to alt-zoom inside the room, Second Life’s camera will become confused and start behaving
as though you are trying to look at the outside of the prim. This can be annoying, so using a
hollow prim as a room is recommended only when prim conservation is your highest priority.
Figure 3.4: Transforming a tube into a Möbius
strip using twist
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