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418 Chapter 5: Creating Geometry
Radius—
Sets the radius of the ring . You set the
initial Radius value when you drag to create the
ring array.
Amplitude—Sets the amplitude of the ring’s sine
curve, in active units. Amplitude is a height offset
from the local origin of the center dummy object.
Cycles—Sets the number of cycles in the ring’s sine
curve. When Cycles is 0.0, the ring is flat. When
Cycles is 1.0, the ring is tilte d. Greater v alues
increase the number of peaks in the curve.
Phase—Offsets the phase of the wave. T hat is,
it has the effect of movi ng the wave along the
circumference of the ring. Whole values have no
effect; only fractional values do.
Number—Sets the number of boxes in the ring .
Sunlight and Daylight
Systems
Create panel > Systems > Sunlight button and Daylight
button
Create menu > Lights > Daylight System
Create menu > Systems > Daylight System
The Sunlight and Daylight systems use lig ht in
a system that follows the geog raphically correct
angle and movement of the sun over the ear th at
a given location. You can choose location, date,
time, and compass orientation. You can also
animate the date and time. This system is suitable
for shadow studies of proposed and existing
structures. In addition, you can animate Latitude,
Longitude, North Direction, and Orbital Scale.
Sunlight and Daylight have a similar user interface.
Thedifferenceisthat:
•Sunlightusesadirectional light (page 2–1293).
•DaylightcombinesSunlight (page 3–1018)
and Skylight (page 3–1012).TheSunlight
component can be an IES Sun light (page
2–1309),anmr Sun light (page 2–1319),or
astandardlight(atarget direct light (page
2–1292)). The Skylight component can b e an
IES Sky light (page 2–1312),anmr Sky light
(page 2–1318),oraSkylight (page 2–1296).
•TheIESSunandIESSkylightsare
photometric lights. It is appropriate to use
them if you are creating a rendering that uses
radiosity (page 3–51) with exposure control
(page 3–293).
• The mr Sun and mr Sky lights are also
photometric, but are intended for use with
the mental ray Sun & Sky (page 2–1313)
solution.
• The Standard light and Skylight are not
photometric. It is appropriate to use them if
your scene uses st andard lighting (Sunlight
with its Directional light works for this, too),
or if you are using light tracing (page 3–44).
Large view shows compass and light in a viewport. The
resulting rendered images are seen above it.
Note: When you create a sunlight system or a
daylight system that uses a target direct light for
the sun, the directional light’s hotspot is set to
encompass all geometry in the scene, so that
shadows will render correctly. Specifically, the