9

Light Tracer 45
Character lit by Skylight and one spotlight, and rendered with
light tracing
Model by Sonny Sy — [e-mail] —
www.geocities.com/orange_3D
The Lig ht Tr acer provides soft-edged shadows
and color bleeding for brightly-lit scenes such as
outdoor scenes. I t is typically used in conjunction
with a Skylight (page 2–1296).Unlikeradiosity
(page 3–51), the Light Tracer does not attem pt to
create a physically accurate model, and can be
easier to set up.
Outdoor scene lit by Skylight and rendered with light tracing
Tip: While you can use light tracing for indoor
scenes, radiosity is usually the better choice in
such cases.
Pr evi ewin g th e Ef f ect of L ight Tra cing
• To get a quick preview of the effect the
Light Tr acer will have, lower the values of
Rays/Sample and Filter Size.
The result will be a grainy version of the full
effect.
• Another way to get a quick preview is to m a ke
sure Adaptive Undersa mpling is turned on.
In this group, set the Initial Sample Spacing
sampling and the Subdivide Down To setting
tothesamevalue. IntheGeneralSettings
group, lower the value of Rays/Sample, and set
Bounces equal to 0.0. This g ives a rather blotchy
but fast preview of the rendering. Increase the
Rays/Sample and Filter Size values to improve
the image quality.
In general, you can get good, fairly quick
resultswithalowerFilterSizevalueaslongas