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96 Chapter 17: Rendering
If the active renderer is not already the mental
ray renderer, go to the Common p anel, and
on the Assign Renderer rollout, click the “...”
button for the Production renderer . A Choose
Renderer dialog is displayed. Highlight “mental
ray Renderer” in the list, and then click OK.
Leave the Render Scene dialog open, or
minimize it.
3. Open the Material E ditor. Use t he mental
ray Connection rollout (page 2–1461) to assign a
volumeshadertotheVolumecomponent.
Another technique would be to use the mental
ray material (page 2–1544), and assign a shader
totheVolumecomponent.
4. Also on the mental r ay Connection rollout,
clicktounlocktheSurfacecomponent.Click
the button and use the Browser to a ssign the
Transmat (physics) shader to the surface.
(If you are using t he mental ray material,
you don’t need to first unlock t he Surface
component.)
5. Apply the material to objects you wish to use as
shaded volumes.
mental ray Displacement
Displacement shading with the mental ray
renderer is similar to displacement mapping (page
2–1511) of standard materials. One advantage
of using mental ray displacement is that the
additional polygons of displaced surfaces are
stored only in the mental ray scene database, not
in your 3ds Max scene, so they do not increase
the memory requirements of your scene, except
at render time. This can be a big improvement
in performance over displacement mapping with
standard materials and the scanline renderer.
Procedure
To add displacement to a mental ray rendering:
1.
Choose Customize > Preferences. Go to the
mental ray panel, and turn on Enable Mental
Ray Ex tensions.
2. On the Render toolbar, click Render
Scene.
If the active renderer is not already the mental
ray renderer, go to the Common panel, and
on the Assign Renderer rollout, click the “...”
button for the Production renderer . A Choose
Renderer dia log is displayed. High light “mental
ray Renderer” in the list, and then click OK.
Leave the Render Scene dialog open, or
minimize it.
3. Open the Material Editor.
4. On the mental ray Connection rollout,
click to unlock the Displacement component.
Click the button and use the Browser to assign
a displacement shader to the surface.
Wa rn in g : This overrides any displacement assigned
to the base material as a standard map.
Another technique would be to use the mental
ray material (page 2–1544), and assign a shader
to the Displacement component. (If you are
using the mental ray material, you don’t need to
first unlock the Displacement component.)
5. Ap ply the material to objects you wish to show
the displacement.
mental ray Contour Shading
Contourshadingletsyourendervector-based
contourlines. Contoursaresimilartotheink
component of the Ink ’n Paint material.