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1412 Chapter 16: Material Editor, Materials, and Maps
Luminance scale takes self-illumination mapping
(page 2–1343)
into account. You can use this to
model effects such as a computer monitor in a
darkened room.
The Special Effects group of the Advanced Lighting
Override material also has a control for adjusting
the quality of
bump mapping (page 2–1347) in
areas of indirect lighting.
Pr ocedur es
To adjust a material’s reflectance and transmittance:
1.
Create a material for your scene.
2. Click the Type button and choose Advanced
Lighting Override.
3. In the Replace Material dialog (page 2–1300) ,
choose Keep Old Material As Sub-Material, and
click OK.
4. AdjusttheReflectanceScaleandTransmittance
Scale parameters. As you do, watch the
Reflectance and Transmittance display, and
make sure the values are good for a radiosity
solution. For example, 85 percent reflectance is
aboutthehighestthatwillworkwithradiosity.
Most real-world mater ials have much lower
reflectance.
See
Reflectance and Transmittance Display
(page 2–1274)
for some reflectance properties
of real-world materials.
To mak e a self-illuminating material emit r adiosity
energy :
1.
Create a material that is self-illuminating.
2. Click the Type button and choose Advanced
Lighting Override.
3. In the Replace Material dialog (page 2–1300) ,
choose Keep Old Material As Sub-Material, and
click OK.
4. Increase the value of Luminance Scale to
have the material emit e nergy for radiosity
processing.
Interfa ce
Override M aterial Physical Properties group
These parameters directly control the base
material’s advanced lig hting properties.
Wa rn in g: There is no problem with reducing the default
scale, but increasing it for any of these parameters might
cause colors to “burn out”: if the scale is too great, they
render as pure white, appearing overexposed.
Reflectance Scale—
Increases or decreases the
amount of en ergy the material reflects. Range=0.1
to 5.0. Default=1.0.
Reflectance Scale increases or decreases the energy of
reflected rays.
Tip: Don’t use this control to increase
self-illumination. Use the Luminance Scale
instead. Luminance Scale is in the Special Effects
group (below).