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1340 Chapter 16: Material Editor, Materials, and Maps
ofthemapreplacethematerial’sdiffusecolor
component. This is the most common kind of
mapping.
Mapping the diffuse color is like painting an image
on the surface of the object. For example, if y ou
wantawalltobemadeoutofbrick,youcan
choose a map with an image of bricks, such as
Bricks (page 2–1468) .
By default, diffuse mapping applies the same map
to the
ambient color (page 3–1002) as well. You
seldom need to use a different map for diffuse and
ambient components.
It isn’t strictly necessary to lo ck the ambient and
diffuse maps. By turning the lock off and using
a different map for each component, you can
obtain interesting blend effects. But in general, the
purpose of diffuse mapping is to simulate a sing le
surface t hat is more complex than a basic m aterial,
and for this purpose the lock should be on.
Procedure
To map t he dif fus e color:
1.
Make sure the ambient and diffuse components
have their maps locke d. This button is to the
right of the map shortcut buttons for Ambient
and Diffuse on the Basic Parameters rollout,
andontheMapsrolloutinasimilarposition.It
is on b y default. When it is on, the map button
for the ambient color component is unavailable.
2. Click the Map button for Diffuse color.
The
Material/Map Browser (page 2–1291) is
displayed.
3. Choose from the list of map types, and then
click OK.
TheMaterialEditorisnowatthemaplevel,and
displays controls for the map parameters.
4. Use the map controls to set up the map.
Diffuse Level Mapping
Material Editor > Standard m aterial > Shader Basic
Parameters rollout > Anisotropic, Oren-Nayar-Blinn, or
Multi-Level shader > Maps rollout > Diffuse Level button
Mapping diffuse level
Top: No mapping
Bottom: Mapping diffuse level with a bitmap
Yo u c a n s e l e c t a b i t m a p f i l e o r procedural map
(page 3–1091)
to control the Diffuse Level
parameter. White pixels in the map leave the
diffuse level unchanged. Black pixels reduce the
diffuse level to 0. Intermediate values adjust the
diffuse level accordingly.
The diffuse level parameter is available with the
Anisotropic (page 2–1321) , Oren-Nayar-Blinn
(page 2–1323)
,and Multi-L evel (page 2–1323)
shaders.
Reducing the Amount of the diffuse level map
reduces the map’s effect, and increases the effect of
theDiffuseLevelvalueontheBasicParameters