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Rendering Algorithms Rollout (mental ray R e nderer) 113
Render ing Algorithms R ollout
(menta l r ay Rend erer )
Rendering menu > Render > Render Scene dialog >
Renderer panel > Rendering Algorithms rollout
Main toolbar > Render Scene > Render Scene dialog >
Renderer panel > Rendering Algorithms rollout
Note: The Renderer panel appears only when the mental
ray renderer is the currently active renderer.
Thecontrolsinthisrolloutletyouchoosewhether
to render using ray-tracing, scanline rendering,
or both. You can also choose the method used to
accelerate ray-tracing.
The controls labeled Trace Depth limit the number
of times each ray can be reflected, refracted, or
both.
Procedure
To s et t r a ce dept h f or r ef l ecti ons and r e fr a cti ons :
1.
Count the number of times y ou want an object
to be reflected or refracted in the scene.
2. On the mental ray: Rendering Algorithms
rollout, set Max Reflections to the number of
reflections you want, and Max R efractions to
the number of refract ions you want.
3. Set Max Depth to equal the value you chose for
Max Reflections plus the value you chose for
Max Refractions.
Thegreaterthenumberofreflectionsand
refractions, the more slowly your scene will
render. On the other hand, too l ow a value
for Max Reflections or Max Refractions (or
Max Depth, controlling both) can make your
rendering look unrealistic.
Interfa ce
By default, both Ray Trace and Scanline are
enabled, which lets the mental ray renderer use
a combination of
ray tracing (page 3–87) and
scanli ne rendering to render the scene. Sca nline
rendering is used for direct illumination (“primary
rays”) only; ray tracing is used for indirect
illumination (caustics and global illumination) as
well as reflections, refractions, and lens effects.
Youcandisableoneortheotheroption,butnot
both. For example, if only ray tracing is enabled
and you turn it off, 3ds Max enables scan line
rendering.
Scanline group
Enable—When on, the renderer can use scanline
rendering . When off, the renderer uses the
ray-tracing method only. Scanline rendering
is faster than ray t racing, but cannot generate
reflections, refractions, shadows, depth of field, or
indirect lighting. Default=on.