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1010 G lossa ry
The mental ray manual, Programming mental ray,
describes how to write custom shaders.
Shaders (Standard Materials)
For a standard material (page 2–1465),theshader
is the algorithm that controls how the material
responds to light. Shaders especially control how
highlights appear. They also prov ide a material’s
color components, and control its opacity,
self-illumination, and other sett ings. Shaders are
often named for their inventors; they can a lso be
named for the effect they prov ide. See Shading
Type (page 2–1398).
Sample s of different shadin g for a standard material
1. Anisotropic
2. Blinn
3. Metal
4. Multi-layer
5. Oren-Nayar-Blinn
6. Phong
7. Strauss
8. Translucent
For each material, one of the available shaders
is always active. You choose the shader on the
material’s Shader Basic Parameters rollout (page
2–1466).
The raytrace material (page 2–1512) uses a subset
of the s tandard materi al shaders: Anisotropic,
Blinn, Metal, Oren-Nayar-Blinn, and Phong.
You cho ose the raytrace material’s shader on the
material’s Raytrace Basic Parameters rollout (page
2–1514).
The other types of m aterials in 3ds Max don’t g ive
you a choice of shader.
Materials(andlightsandcameras)usedwith
the mental ray renderer (page 3–78) can use
ment al ray shaders, which are not the same as the
standard material shaders. See Shaders (mental ray
Renderer) (page 3–1009).
Shadow Maps (Light Objects)
Example of shadow-mapped shadows
Ashadowmapisabitmapthattherenderer
generatesduringapre-renderingpassofthe
scene. Shadow maps don’t show the color cast by
transparent or translucent objects . On the other
hand, shadow maps can have soft-edged shadows,
which ray-traced shadows cannot.
A shadow-map is projected f rom the direct ion
ofthespotlight. Thismethodprovidesasofter