Shading Group attributes
In the Shading
Group’s Attribute Editor, the mental
ray section contains the following options:
Flags
These are the options
in the Flags section.
- Opaque
-
Turn this on if the material
is fully opaque. It should assist in speeding up mental ray rendering.
- Transparency Threshold
-
Tweak this transparency threshold so that
all surface points that are less opaque than specified by this attribute
will be considered non-existent. For example, a value of 0.05 removes
all surface points with a transparency of 99.5% or more.This allows
your object to appear cut out from the texture. An example is to
map an image of a tree to a flat plane and use opacity to cut away
the parts of the tree that are not there.
Contours
These are the options
in the Contours section. Each shading
group can have individual contour rendering attributes defined.
Set the following options to achieve the desired look. See also
Contours in
the Rendering guide.
- Enable Contour Shading
-
Enables contour shading
for all objects associated with the shading group.
- Color
-
The color of the contour
lines. This attribute can only be a color and cannot have a procedural
or texture map connected to it.
- Alpha
-
The alpha of the contour
lines.
- Width
-
The width of the contour
lines.
- Relative Width
-
If off, Width is
specified as (fractional) number of pixels. If on, Width is
specified in percents of the horizontal image resolution thus maintaining
the relative contour size if the resolution changes.
- Absolute Width
-
If on, Absolute
Width is specified in percents of the horizontal image
resolution set by the user.
Custom Shaders
These are the options
in the Custom Shaders section.
- Suppress all Maya Shaders
-
Use this for backwards
compatibility as it disables automatic translation of Maya shaders. Only
the mental ray ports are evaluated and exported.
- Export with Shading Engine/Export
with Volume Sampler
-
When turned on, these
both insert additional helper shaders into the export stream. These shaders
are required if you want to write custom shaders that cooperate
with the Maya base shader package delivered with mental ray for Maya.
These options are for advanced mental ray for Maya users only.
NoteThe Export
with Shading Engine attribute is available for backward compatibility.
It should not be used for tuning and should be disabled in most cases.