8

1178 Chapter 15: Lights and Cameras
Note:
You can also prevent objects from casting
shadows by exclu ding them from a light.
Inter face
Light Type group (Modify pane l)
On—(Both Create panel and Modify panel) Turns
thelightonandoff.WhenOnison,shadingand
rendering use the light to illuminate the scene.
When On is off, the light is not used in shading or
rendering. Default=on.
In viewports, the interactive renderer shows the
effect of turning lights on or off.
Light Type List—Changes the type of the light.
If you have selected a
standard light ty p e (page
2–1142)
, the light can be changed to an omni,
spot, or directional light. If you have selected a
photometric light t ype (page 2–1155) ,youcan
change the light to a p oint, linear, or area light.
This parameter is available only in the Modify
panel.
Targeted—When on, the light is targeted. The
distance between the light and its target is
displayed to the right of the check box. For a f ree
light, you c an set this value. For target lig hts, you
can change it by turning off the check box, or by
moving the light or the light’s t arget object.
Shadows group
On—Determines whether the current light casts
shadows or not. Default=on.
Sha dow M ethod drop-down list —Determines
whether the renderer uses
shadow maps (page
3–1104)
, ray-traced shadows (page 3–1094) ,
advanced ray-traced shadows (page 3–1094) ,or
area shadows (page 3–1005) ,togenerateshadows
for this light.
The“mentalrayShadowMap”typeisprovided
for use with the
mental r ay renderer (page 3–77) .
When you choose t his shadow type and enable
shadow maps (on the
Shadows & Displacement
rollout (page 3–111)
of the Render Scene
dialog), shadows use the m ental ray shadow-map
algorithm. If this type is chosen but you render
w ith the default scan line renderer, no shadows
appear in the rendering.
Note: When shadow maps are enabled and the
shadow map type is Shadow Map, the mental ray
renderer attempts to translate the shadow map
settings into comparable settings for mental ray
shadow maps. (The results mig ht not be what
you expected.) In all other cases, the mental ray
renderer generates ray-traced shadows.
Each shadow t ype has its particular cont rols:
•
Advanced ra y-tr aced shadows—See Advanced
Ray-Traced Parameters Rollout (p age 2–1200)
and Optimizations Rollout (page 2–1206) .
•
Area shadows—See Area Shadows Rollout (page
2–1202)
and Optimizations Rollout (page
2–1206)
.
•
mental ra y sha dow ma ps—See mental ray
Shadow Map Rollout (page 2–1205)
.
•
Ray-traced shadows—See Ray-Traced Shadow
Parameters Rollout (page 2–1207)
.
•
Shadow maps—See Shadow Map Parameters
Rollout (page 2–1208)
.