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1152 Chapter 15: Lights and Cameras
Increasing the number of rays increases the quality of your
image. However, it also increases rende ring time.
Ray Bias—The closest distance at which objects
can cast shadows on a given point in the scene.
Settingthisvalueto0cancausethepointtocast
shadows upon itself, and setting it to a large value
canpreventobjectsclosetoapointfromcasting
shadows on the point.
mr A r ea Omni L ight
Create panel > Lights > m r Area Omni button > Area Light
Parameters rollout
When you render a scene using the mental ray
renderer (page 3–77)
,anareaomnilightemits
light from a spherical or cylindr ical volume, rather
than from a point source. With the default scanline
renderer, the area omni light behaves like any other
standard omni light.
Note: In3dsMax,areaomnilightsarecreated
and supported by a MAXScr ipt script. Only the
mental ray renderer uses the parameters on the
Area Light Parameters rollout. See
Enhancements
to Standard Features (page 3–84)
for more details.
Tip: Area lights take longer to render than point
lights. To create a quick test (or draft) rendering,
youcanusetheArea/LinearLightsasPointLights
toggle in the
Common Parameters rollout (page
3–27)
of the Render Scene dialog to speed up your
rendering.
See also
mr Area Spotlight (page 2–1153)
Procedures
To create an area omni light:
1.
OntheCreatepanel,clickLights.
2. On the Object Type rollout, click mr Area
Omni.
3. Click in a viewpor t.
4. Settheshapeandsizeofthearealightinthe
Area Light Parameters rollout.
Whileyouusethespinnerstoadjustthesize
of the area l ight, a gizmo (yellow by default)
appears in viewports to show the adjusted
size. This gizmo disappears once you finish
adjusting the value.
Tip: YoucanuseRotatetoadjusttheorientation
of a cylindrical area omni light. However, no
gizmoappearswhileyourotatethelight.
To convert a standard 3ds Max light to an area light:
1.
Selectoneormorelights.
2. Go to the Utilities panel.
3. On the Utilities rollout, click MAXScript.
The MAXScript rollout is displayed.
4. On the MAXScript rollout, choo se “Convert To
mr Area Lights” from the Utilities drop-down
list.
The “Convert To mr Area Lights” rol lout is
displayed.
5. On the “Convert To mr Area Lights” rollout,
click Convert Selected Lights. A MAXScript
alertisdisplayed,thatsays"DeleteOldLights?"
Click Yes to delete the original light and replace
it with the area light. Click No to leave the
original lig ht in place. If you click No there are