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88 Chapter 17: Rendering
This is equivalent to the preference, Open Message
Window On Error.
Cle ar —Click to clear all messages from the
messages area.
menta l r a y Concepts
Thesetopicsdescribewhatthementalrayrenderer
can do, and explain how it accomplishes these
effects. For more technical detail about mental
ray c apabilities, see the mental ray manual,
Programming mental ray, and Rendering with
mental ray, book 1, by Thomas Driemeyer (New
York: Springer Verlag, 1999).
See also
Ray-Traced Reflections and Refractions with the
mental ray Renderer (page 3–88)
Shadows with the mental ray Renderer (page 3–89)
Motion Blur with the mental ray Renderer (page
3–89)
Depth of Field with the mental ray Renderer (page
3–90)
Caustic Lighting Effects (page 3–92)
Global Illumination with the men tal ray Renderer
(page 3–93)
mentalrayVolumeShading(page3–95)
mental ray Displacement (page 3–96)
mental ray Contour Shading (page 3–96)
Ray-Traced Reflections and
R efr actions wit h the mental ray
R enderer
The mental ray renderer can generate reflections
and refractions by ray t racing. Ray tracing traces
the p ath of rays sampled from the lig ht s ource.
Reflections and refractions generated this way are
physically accurate.
Ray-traced reflections and Refractions
To reduce the time required to generate reflections
andshadows,raysarelimitedbytrace depth.Trace
depth limits t he number of times a ray can be
reflected, refracted, or both.
You can turn off ray tr acing. In this case, the
mental ray renderer uses scanline rendering
only. Turning off ra y tracing makes the controls
for a ll the effects t hat are specific to mental ray
unavailable in the Renderer’s rollouts.
Ray tracing uses one of two ray-trace acceleration
methods (page 3–1000).
You enable ray tracing and set trace depth in the
Render Scene dialog > Renderer panel > Rendering
Algorithms rollout (page 3–116).