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1514 Chapter 16: Material Editor, Materials, and Maps
Render group
These controls affect how the refraction should
behave in animations.
First Frame Only—Tells the renderer to create the
refracted image only on the first frame.
This is the fastest option. You can use it if the
camera and refractive object don’t move.
Every N th Fra me—Tells the renderer to regenerate
therefractedimagebasedonthe
framerate(page
3–1038)
set by the spinner.
Every single f rame provides the most accurate
result, but takes longest to render.
Use Envi ronment Ma p—When off, environment
maps are ignored by the refraction dur ing
rendering. It’s useful to turn it this off when
you have refractions in the scene and you’re
rotoscoping against a flat screen environment map.
Ascreenenvironmentmapdoesnotexistin3D
space t he way the other environment map types
do, and will not render properly. Default=on.
Refraction group
These controls are specific to the Thin Wall
Refraction effect:
Thi ckness O f fset—Affects the size of the refractive
offset, or jog effect. At 0, there’s no offset, and the
object can appear invisible in the rendered scene.
At 10.0, the offset is at its greatest. Range from 0.0
to 10.0; Default=0.5.
Note: The IOR (index of refraction) spinner in the
parent material’s Extended Parameters rollout also
affects the offset effect.
Bump Map Effect—Affects the magnitude of
refraction due to the presence of a bump map.
This p arameter multiplies the cur rent bump map
Amount in the parent material. Reduce this value
to reduce the effect of the secondary refraction;
increase this value to increase the effect. If there is
nobumpmapassigned,thisvaluehasnoeffect.
Default=1.0.
If there is unevenness in the surface of the
glass, there is a secondary refraction. Thin Wall
Refraction generates this secondary refraction if
the material also has a bump map present. The
algorithm guesses at t he scaling of the secondary
refraction, a nd can create too large an effect. If this
happens, scale the effect down by reducing this
value to less than one.
Raytrace Map Rollouts
R a y tr a cer Pa r a meter s R oll out
Material Editor > Maps rollout > Click a Map button. >
Material/Map Browser > R aytrace > Raytracer Parameters
rollout
This rollout contains the main controls for the
Raytrace m ap (page 2–1508) .
Interfa ce