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Arch & Design Material (mental ray) 1561
Left: No detail distance; Center: 25mm detail distance; Right:
150mm detail distance
This also allows an interesting trick: Set Reflection
> Glossy Samples to 0, which renders reflections
as if they were mirror-perfect, but a lso use
interpolation to introduce blur into this reflection,
and perhaps use High Detail Distance to make
nearby parts less blurry. This is a fast way to obtain
a glossy reflection.
Thefloortilesinthefollowingillustration
are rendered with mirror reflections, and the
blurriness comes solely from the interpolation.
Thisrendersasfastasorfasterthanpuremirror
reflections, yet gives a satisfying illusion of true
glossy reflections, especially when ut ilizing the
High Detail Distance option , as on the r ig ht.
Left: No detail distance; Right: With detail distance
Single Sa mple f rom Environment—Creating
realistically blurry glossy reflections normally
requires taking multiple samples from the
environment, which can result in grainy,
slow-rendering environment reflections. With
this check box on, mental r ay instead takes only
one sample, thus preventing t he grain. This
also prevents blur ring the environment, so it is
best used together with a local, “pre-blurred"
environment m ap. You can do the pre-blurring in
an image-processing program or with the Material
Editor > Coordinates rollout (page 2–1625) >Blur
and Blur Offset settings.
Refractive interpolation group
Neighbor ing poi nts to look up —Defines how many
stored gr id points (in an N by N group around the
currently rendered point) are looked up to smooth
out refrac tive glossiness. The default is 2; hig her
values tend to “smear” the glossiness more, but are
hence prone to more oversmoothing artifacts.
Special Purpose Maps rollout
Lets you apply bump, displacement, and other
maps. Each left-justified setting has a check box
forenablinganddisablingthemap,andabutton
for defining the map.
Bump—Lets you apply a bump map and multiplier.
Do not a pply bumps to t he dif fuse sha ding—When
off, the bumps apply to all shading components:
diffuse, highlights, reflections, refractions, etc.
When on, bumps are applied to all components
exceptthediffuse.Thismeansbumpsareseenin
reflections, highlights, etc. but the diffuse shading
showsnobumps. Itisasifthematerial’sdiffuse
surfaceissmooth,butiscoveredbyabumpy
lacquer coating.