Used to achieve effects such as gas or clouds.
You can software render particles as thin gas, cloud, thick cloud,
blobby surface or tube.
Volume material
which can be connected to the volume port of a shading group. The
initialParticleSE is a shading group that has a lambert material connected
to its Surface port, and a particle
cloud material connected to its Volume port.
You can connect the particle cloud shading group to a particle emitter
to achieve effects such as gas or clouds. You can software render
particles as thin gas, cloud, thick cloud, blobby surface or tube.
Color, Transparency,
and Incandescence can be set to
a fixed value, or texture mapped over the particles’ lifetime. If
mapped, the V values of the map are mapped onto the particles’ lifetime.
Find this material in
the
Create bar.
- Color
-
The
basic color of the particle cloud. The default color is a green-blue.
- Transparency
-
Controls how much you can see through
the particle cloud. It is a color, so that you can control the transparency
of the red, green, and blue channels separately. To make the cloud more
opaque, set transparency to be darker. To make the cloud more transparent,
set transparency to be brighter.
- Incandescence
-
Use Incandescence to
make the particle cloud brighter, as though it were a light source.
By default, Incandescence is black, meaning
no glow is added.
NoteWhen Incandescence is
turned on, although the particle cloud glows, it does not cast light
on other objects in the scene.
- Life Color
-
Determines the color at a particular
time in the life of the particle. You can use the Particle Sampler
Info node to animate this attribute over a particle’s
lifetime.
- Life Transparency
-
Determines
the transparency at a particular time in the life of the particle.You
can use the Particle Sampler Info node
to animate this attribute over a particle’s lifetime.
- Life Incandescence
-
Determines
the incandescence at a particular time in the life of the particle.You
can use the Particle Sampler Info node
to animate this attribute over a particle’s lifetime.
NoteLife
Color, Life Transparency, and Life Incandescence are
driven by the particle age (the texture defines color, transparency,
and incandescence, all of which get their UV information from the particleSamplerInfo utility node).
The particleSamplerInfo utility
node is created automatically at the time the texture is created.
- Glow Intensity
-
Controls how much of a halo-like glow
effect is added to the particle cloud. This glow effect is added
as a post-process, after the rendering is completed. Glow
Intensity is zero by default, meaning that no glow is
added.
Transparency
- Density
-
Similar
to transparency; it controls how dense the cloud of particles appears
to be, and therefore how much of the background can be seen through
it. Increase this value to make the cloud more dense.
- Blob Map
-
Specifies a scaling factor applied
to the transparency of the particle cloud. You can connect a 3d
texture to it in order to give some internal texture or shape to
the cloud beyond what it gets from the particles.
- Roundness
-
Controls the noise’s irregularity. The smaller
the value, the less rounded the shape.
- Translucence
-
Specifies
a scaling factor for density that is used only to compute shadows.
The larger the translucence value, the more light penetrates. The
formula is:
density
* (1 - translucence)
Built-in Noise
- Noise
-
Controls
the jitteriness within the particle cloud. If it is set to zero,
the cloud looks very smooth and uniform throughout. As the amount
of noise increases, the cloud appears noisier, like static on a
television screen. Noise is set to 0.75, by default.
- Noise Freq
-
Determines the size of the noise artifacts
when Noise is turned on. Higher
values of Noise Frequency produce smaller,
finer artifacts, and lower values produce larger, coarser artifacts.
If Noise Frequency is set to zero,
that is the same as turning Noise off.
- Noise Aspect
-
Controls the distribution of the noise
(when Noise is turned on). It is
zero by default, meaning the noise is equally distributed in X and
Y. Positive values make the noise run perpendicular to the particle’s
path. Negative values make the noise run more parallel to the path.
- Noise Anim Rate
-
Specifies
a scaling factor that controls the rate of built-in noise changes
during an animation.
- Solid Core Size
-
Determines
the size of the core, which is the area where the particle is opaque.
Surface Shading Properties
- Diffuse Coeff
-
Controls how much of the light in the
scene is reflected from the particles. Most materials absorb some
of the light falling on them, and scatter the rest.
The default value is
0.0. If you set this to 1.0, all the light falling on the material
is reflected. Use a high value when creating dense clouds. If you set
this to 0.0 (the minimum), no light is reflected and no surface
shading occurs.
The surface color is
modulated by the transparency. This value can be greater than 1.0, so
the surface property can still appear even when the material is
transparent.
- Surface Color
-
Specifies the basic color of the particle
cloud surface (as opposed to the inside of the cloud). Diffuse
Coeff must be set to a value greater than 0 to enable
this option.
- Bump Mapping
-
Makes
the surface appear rough or bumpy by altering surface normals (during
rendering) according to the intensity of the pixels in the bump
map texture. Diffuse Coeff must be set to a
value greater than 0 to enable this option. (A bump map does not
actually alter the surface. A silhouette of the surface appears
smooth).
- Translucence Coeff
-
Simulates
the way light diffusely penetrates through translucent objects.
This means that when light shines on one side of the object, the other
side is partially illuminated. You can use this to create effects
such as clouds, fur, hair, marble, jade, wax, paper, leaves, and
so on. If you set Translucence Coeff to 0 (the
default), no light shows through the object. If you set Translucence
Coeff to 1, all the light shows through. Diffuse
Coeff must be set to a value greater than 0 to enable
this option.
- Surface Shading Shadow
-
Determines
if the surface shading is combined with the pre-illumination, which
contains shadows, if enabled (see the Filter Radius attribute
description next). Diffuse Coeff must be set to
a value greater than 0 to enable this option.
Pre-illumination Controls
- Filter Radius
-
Volumetric particles use pre-illumination, which
evaluates the lighting at each particle’s center by default. This
can sometimes cause popping if the illumination changes too fast
in an animation, and is especially noticeable if Surface
Shading Shadow is on.
Filter radius lets you
filter the pre-illumination results so the value at each particle’s
center is the average of all the pre-illumination results within the
filter radius. Higher values increase render time but produce smoother
images.