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84 Chapter 17: Rendering
Enha ncements to Sta ndar d
Fe atu re s
The primary interface to the mental ray renderer
consists of rollouts on the Render Scene dialog.
You must use t he Assign Renderer rollout to
choose the m ental ray renderer, as describe d the
"Procedures" section of
mental ray Renderer (page
3–77)
.
Inaddition,objectproperties,lights,andthe
Material Editor have additional controls to support
mental ray rendering.
Obj ect Pr oper t ies Enha ncements
Several new parameters have been added to the
mental ray panel (page 1–121) of the Object
Properties dialog. These options support the
mental ray indirect illumination features of
caustics (page 3–91) and global illumination (page
3–92)
.
LightObjectEnhancements
Along with the mental ray renderer , new area light
objects and new light sett ings are provided.
New Light Objects
Area lights (page 3–1004) areafeatureofthe
mental ray renderer. Instead of emitting light from
a point source, they emit light from a broader area
around the source. There are two mental ray area
lights:
mr Area Omni Lig ht (page 2–1152) and mr
Area Spotlight (page 2–1153)
. Area lights create
soft-edged shadows. This can help improve the
realism of your rendering.
Note: To render soft-edged shadows, shadows
must be ray-traced, not shadow-mapped: see
the Renderer pa nel >
Shadows & Displacement
Rollout (page 3–111)
.
In 3ds Max, area lights are created and
supported by the MA XScript scripts,
light-mentalray_areaomni.ms and
light-mentalray_areaspot.ms .Both
scripts are installed in the directory
\3dsmax\stdplugs\stdscripts\ .Becauseof
this, when you create an area light, you actually
createatargetspotoromnilight. Forthislight,
the mental ray renderer uses the parameters on the
Area Light Parameters rollout. If you render w ith
the default scanline renderer, the light behaves
like any other target spot or omni light. (You can
changealightfromonetypetoanotherusing
theTypedrop-downlistinthelight’sGeneral
Parameters rollout.)
For area lights rendered with the mental ray
renderer, you can stil l set and use other lighting
parameters,suchascolor,theMultipliervalue,
the spotlight cone, and so on. Shadow maps are
an exception. T he mental ray renderer ignores
the light’s lo cal shadow map sett ings. Area lights
always use r ay-traced shadows.
Tip: Yo u c a n u s e a M A X S c r i p t u t i l i t y t o c o n v e r t
standard 3ds Max lig ht objects to area lights, as
described in the Procedures section of the area
light topics.
New Light S ett ings
The
mental ray Indirec t Illumination rollout
(page 2–1187)
has been added to light objects
to support the mental ray renderer’s indirect
illuminat ion effects of
caustics (page 3–91) and
global i llumination (page 3–92) .
The
mental ray Light Shader rollout (page 2–1189)
has been added so you can add mental ray light
shaders to light objects.
Impor tant: To see th e mental ray rollouts for lights, you
must use
mental ray Preferences (page 3– 86 7) to enable
mental ray extensions. These rollouts appear only on the
Modify panel. They don’t appear on the Create panel.