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106 Chapter 17: Rendering
Caustics and Global Illumination
Rollout (mental ray Renderer)
Rendering menu > Render > Render Scene dialog
> Indirect Illumination panel > Caustics and Global
Illumination rollout
Main toolbar > Render Scene > Render Scene dialog
> Indirect Illumination panel > Caustics and Global
Illumination rollout
Note: The Indirect Illumination panel appears only when
the mental ray renderer is the active renderer.
The controls in this rollout are for the effects of
caustics (page 3–92) and global illumination (page
3–93).
Pr ocedur es
To r ender with caustics:
1.
Select each object you want to generate caustics,
either by reflection or refraction. Right-click
andchooseProperties,thenonthementalray
panel of the Object Properties dialog, turn on
Generate Caustics.
Objects receive caustics by default. If you t hin k
this value might have changed for the objects
you want to receive caustics, use those objects’
Object Properties dialog to make sure Receive
Caustics is turned on. Also, to speed rendering
time, you might want to turn off Receive
Caustics for those objects th at don’t need to
show them.
2. In the Render Scene dialog, go to the Caustics
And Global Illumination rollout and turn on
Caustics.
3. Adjust t he caustics parameters to get the effect
you want.
4. Render the scene.
To r ender wi th global il lumina tion:
1.
Select each object you want to generate
global illumination. Right-click and choose
Properties, then on the mental ray panel of the
Object Properties dialog, turn on Generate
Global Illuminat ion.
Objects receive global illumination by default. If
you think this value might have changed for the
objects you want to receive global illumination,
use those objects’ Object Properties dialog
to make sure Receive Global Illumination is
turned on. Also, to speed rendering time,
you m ight want to tur n off Receive Global
Illumination for those objects that don’t need it.
2. In the Render Scene dialog, go to the Indirect
Illumination panel > Caustics And Global
Illumination rollout and turn on Global
Illumination.
3. Adjust the global illumination parameters to
get the effect you want.
4. Forthefinalrendering,turnonFinalGatheras
well as Global Illumination. See Final Gather
Rollout (mental ray Renderer) (page 3–111).
5. Render the scene.