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1142 Chapter 15: Lights and Cameras
Trans p. (Transpare ncy)—
When on, turns on
transparency for advanced ray-traced and area
shadows. Has no effect on shadow-mapp ed or
standard ray-traced shadows. Default=off.
The shadow transparency control is on the
Optimizations rollout (page 2–1206) .
Int . (I ntegr it y )—For advanced ray-traced shadows
or area shadows, sets the Shadow Integrity. See
Advanced Ray-Traced Parameters Rollout (page
2–1200)
or Area Shadows Rollout (page 2–1202) .
Default=1.
Qual. (Qua lit y)—F o r advanced ray-traced shadows
or area shadows, sets the Shadow Quality. See
Advanced Ray-Traced Parameters Rollout (page
2–1200)
or Area Shadows Rollout (page 2–1202) .
Default=2.
Decay—(StandardLightsonly.) Setsthetype
ofdecay: None,Inverse,orInverseSquare.
See
Attenuation Parameters (page 2–1190) .
Default=None.
Start—(Standard lig hts only.) Sets the start range
for decay. See
Attenuation Parameters (page
2–1190)
.Default=0.0.
Lengt h—(Photometric lights only.) Sets the Length
value for Linear and Area photometric lights. See
Linear Light Parameters Rollout (page 2–1198) or
Area Light Parameters Rol lout (page 2–1198) .
Width—(Photometric lights only.) Sets t he Width
value for Area photometric lights. See
Area Light
Parameters Rollout (page 2–1198)
.
Standard Lights
Standard lights are computer-based objects that
simulate lights such as household or office lamps,
the light instru ments used in stage and film
work, and the sun itself. Different kinds of light
objects cast light in different ways, simulating
different kinds of real-world light sources. Unlike
photometric lig hts (page 2–1155) ,standardlights
do not have physically-based intensity values.
There are eight typ es of standard light objects:
Target Spotlight (page 2–1143)
Free Spotlight (page 2–1144)
Target Direct Light (page 2–1145)
Free Direct Lig ht (page 2–1147)
Omni Light (page 2–1148)
Skylight (page 2–1149)
mr Area Omni Light (page 2–1152)
mr Area Spotlight (page 2–1153)
Most of the parameters for standard lights are
common to a l l five types. T hese are described in
the following topics:
General Lighting Parameters (page 2–1175)
Intensity/Color/Attenuation Parameters (page
2–1190)
Advanced Effects Rollout (page 2–1185)
Shadow Parameters (page 2–1181)
mental ray Indirect Illumination Rollout (for
Lights) (page 2–1187)
Spotlights and Directional li ghts have rollouts
specific to them:
Spotlight Parameters (page 2–1183)
Directional Par ameters (page 2–1193)
For parameters specific to a particular kind of
light, see that light’s description.
Shadow Parameters
Different rollouts can appear, depending on which
type of shadows y ou have chosen for a light: