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1704 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 Nth Fra me—Tells the renderer to regenerate
therefractedimagebasedontheframe rate (page
3–944) set by the spinner.
Every single frame provides the most accurate
result, but tak es longest to render.
Use Envi ronment M ap—When off, environment
maps are ignored by the refraction during
rendering. It’s usef ul to turn it this off when
you have refractions in the scene and you’re
rotoscoping against a flat screen environment map.
Ascreenenvironmentmapdoesnotexistin3D
space the 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 cknes s Of fs et—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 f rom 0 .0
to 10.0; Default=0.5.
Note: The IOR (index of refrac tion) 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 parameter 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 refrac tion. 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 secondar y
refraction, and can create too large an effect. If this
happens, scale the effect dow n by reducing this
value to less t han one.
Raytrace Map Rollouts
R a y tr a cer Pa r amet er s R ol lout
Material Editor > Maps rollout > C lick a Map button. >
Material/Map Browser > Raytrace > Raytracer Parameters
rollout
This rollout contains the main controls for the
Raytrace map (page 2–1698).
Interfa ce