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1602 Chapter 16: Material Editor, Materials, and Maps
Tip:
Check the reflectance and transmittance
display (page 2–1430) to get an idea of how
the c urrent material will affect the radiosity
sol ution or light-traced rendering.
Creat ing S pecial Ef fects
Self-illumination (page 2–1487) makes an object
appear to glow in ordinary renderings, but does
not contribute energy to the radiosity solution. To
have radiosity processing take a self-i lluminating
material into account, make this material the base
material of Advanced Lighting Override, then
increase the value of Luminance Scale.
Upper left: By default, self-illuminated neon lights do not
influencethescenelight.
Right: Advanced Lighting Override mate rial scales the neo n
lights’ Luminance so the radiosity solution can take it into
account.
Luminance scale takes self-illuminat ion mapping
(page 2–1502) 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 qua lity of bump mapping (page 2–1506) in
areas of indirect lighting.
Procedures
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 2–1456),
choose Keep Old Material As Sub-Material, a nd
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
about the hi ghest that will work with radiosity.
Most real-world materials have much lower
reflectance.
See Reflectance and Transmittance Display (page
2–1430) for some reflectance properties of
real-world materials.
To mak e a self-illuminating material emit radiosity
ener gy :
1.
Create a m aterial that is self-illuminating.
2. Click the Type button and choose Advanced
Lighting Override.
3. In the Replace Material dialog (page 2–1456),
choose Keep Old Material As Sub-Material, a nd
click OK.
4. Increase the value of Luminance Scale to
have the mater ial emit energy for radiosity
processing.