Datasheet

48
PRIM
TORTURE
WORKING
WITH
TINY
PRIMS
BUILDING
BY
THE
NUMBERS
TUTORIAL:
BUILDING A
STAIRCASE
CHAPTER 3
Sheared tubes behave much like
other radially extruded prims, but
you may notice that the tube looks a
little odd when Top Shear is applied to
it. The top and the bottom seem to
have a little distortion in the form of
a bump. But when you look inside the
prim by doing a path cut of B = 0.250
and E = 0.750 you can plainly see that
the distortion is caused by the inside
corners of the base 2D rectangle,
which do not tilt when shear is applied
(Figure 3.8).
■ HOLE SIZE
Hole Size exists only on radially extruded prims. As mentioned in Chapter 2, “Mastering Second Life’s
Basic Building Blocks,” this feature has a very confusing name since its values control the hole size
only indirectly by adjusting the dimensions of the 2D base shape. The X value (which represents the
x-axis) adjusts the hole depth, while the Y value (which pertains to the y-axis) makes the hole smaller
by widening the base shape.
Hole Size is useful for fi ne-tuning tori destined to become vehicle tires or inner tubes. You can
also use it to simulate the cylinder’s hollow effect on a tube.
■ PROFILE CUT
Profi le Cut is available only in radially
extruded prims. This feature is
extremely useful for creating a variety
of complex shapes that look like they
use many more prims than they
actually do!
Let’s explore the Profi le Cut
options by making a little lounge table
out of a tube. Set Hollow to 95 and
Hole Size Y = 0.45. Now do a profi le
cut of B = 0.25 and E = 0.90. As
you can see, we now have a lovely
restaurant table complete with base,
a central stand, and a tabletop, all
with one single prim! If you want to
simulate a tablecloth, set the profi le
cut B = 0.20. By copying and reducing
the size of the table, the same design
can make for attractive low-prim chairs
(Figure 3.9).
Figure 3.8: Shear applied to a tube looks odd. A cross-
section of the prim shows that the rectangular base
shapes are the reason.
Figure 3.9: Aimee’s fi ve-prim patio-furniture set. The
stools are minor variations on the table design.
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