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78 Chapter 17: Rendering
mental ray renderer is optimized to use multiple
processors and to take advantage of incremental
changes for efficient rendering of animations.
Unlike the default 3ds Max renderer, which renders
scanlines from the top of the image downward, the
mental ray renderer renders rectangular blocks
called
buckets . The order in which the buckets
are rendere d c an var y, depending on the metho d
you choose. By default, mental ray uses t he
Hilber t method, which picks the next bucket to
render based on the cost of switching to the next
one. Be cause objects can be discarded from the
memory to render other objects, it’s important to
avoidhavingtoreloadthesameobjectmultiple
times. This is especially important when you have
enabled placeholder objects (see the Processing
panel >
Tr anslator Options rollout (page 3–115) ).
If you use distributed rendering to render a scene,
it might be hard to understand the log ic b ehind
the rendering order. In this case, the order has
been optimized to avoid sending lots of data over
the network. Each CPU is assigned a bucket as the
bucket becomes available, so different buckets can
appear in the rendered image at different times.
See the Renderer panel >
Sampling Quality rollout
(page 3–97)
.
Note: The mental r ay renderer can also be run
in a standalone fashion, using a command-line
interface based on the mi2 or mi3 scene description
format.Thisisdescribedinthemanual
mental ray
Programming,
which is w ritten for programmers
writing custom
shaders (page 3–1103) .
See also
Getting Good Results with mental ray Rendering
(page 3–80)
3ds Max Materials in mental ray Renderings (page
3–82)
mental ray Concepts (page 3–87)
Enhancements to Standard Features (page 3–8 4)
Procedure
To us e the mental r ay render er:
1.
Choose Rendering menu > Render . The Render
Scene dialog displays.
2. On the Common panel, open the Assign
Renderer rollout, then click the “...” button for
the Production renderer.
AChooseRendererdialogisdisplayed.
3. OntheChooseRendererdialog,clicktoselect
mental ray Renderer, and then click OK.
Tip: After you make the mental ray renderer the
active production renderer, you can click Save
As Defaults to make the mental ray renderer the
default renderer for all new scenes. This can be
a convenient way to avoid extra setup time.
Now when you render, the Render Scene dialog
appears with the mental ray controls. You can
choose to render the scene with the built-in mental
ray renderer, or simply to translate the scene
and save it in a
.mi file (page 3–1066) that you
can render later, perhaps on a different system.
Controls for choosing whether to render, save to
a.
mi file, or both, are on the Translator Options
rollout (page 3–115)
.
R enderi ng with the mental r ay
R enderer
Rendering menu > Render > Render Scene dialog >
Common panel > Assign Renderer rollout > Choose
mental ray Renderer as the production renderer.
Main toolbar > Render Scene > Render Scene dialog
> Common panel > Assign Renderer rollout > Choose
mental ray Renderer as the production renderer.
To use the mental r ay translator and renderer, you
must first choose mental ray as the production
renderer, as described the "Procedures" sec tion
below . Once you have chosen mental ray
rendering, the Render Scene dialog displays panels
and rollouts that control the mental ray renderer.