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Advanced Lighting Override Material 1601
material (upper button) or the ba ked material
(lower button).
Render—Use these buttons to choose which
material appears in renderings: the original
material (upper button) or the ba ked material
(lower button).
Advanced Li ghting Ov err ide
Material
Material Editor > Type b utton > M aterial/Map Browser >
Advanced Lighting Override
This material lets you d irectly control the radiosity
properties of a material. Advanced Lighting
Override is always a supplement to a base material,
which can be any renderable material. The
Advanced Lighting Override material has no effect
on ordinary renderings. It affects the radiosity
solution (page 3–51) or light tracing (page 3–44).
Advanced Lighting Overr ide has two main uses:
•Adjustingthematerialpropertiesusedina
radiosity solution or light tracing
• Creatingspecialeffectssuchashaving
self-illuminating objects contribute energ y to
the radiosity solution
As the rollout for the Advanced Lighting Override
material states, you don’t have to apply this
material to obtain a radiosity solution, and most
models wil l never require it.
Impor tant: The mental ray renderer (page 3–78) does not
support the Advanced Lighting Override material.
Obtaining a B etter Image
Materialsthatusedefaultsettingscanbehighly
reflective. This can lead to overexposed or
washed-out radiosity solutions. In general, the
bestwaytoadjustthisistoreducetheHSV
Value (V) of a material color; or, for a bitmapped
material, reduce the RGB Level. In some situations,
Radiosity Override can improve the appearance
of the radiosity solution. Examples of situations
where Radiosity Override can help include color
bleeding and large dark areas:
• You might want to reduce Reflectance Scale
or Color Bleed w hen a large area of color (for
example, a red car p et in a room with white
walls) creates excessive color bleeding. This
mightbephysicallyaccurate,buttheeyeadjusts
for such effects, and the radiosity result might
look better with less reflectance or less color
bleeding.
Left: Excessive bleeding of the floor color onto the walls
and ceiling.
Right: Radiosity Override material reduces the floor’s
reflectance, causing less bleeding.
• You might want to increase Reflectance Scale
when the scene includes a large dark area (for
example, a black floor). This can lead to a very
dark radiosity result. You can maintain the
floor’s color but increase reflectance, giving the
sol ution the colors you want while increasing
its brightness.
The room is lit only by spotlights pointed at the floor.
Increasing reflectance of the floor brightens the entire
room.