User Manual

Table Of Contents
Color Over Life
This standard gradient control allows for the selection of a range of color values to which the
particle will adhere over its lifetime.
The left point of the gradient represents the particle color at birth. The right point shows the
color of the particle at the end of its lifespan.
Additional points can be added to the gradient control to cause the particle color to shift
throughout its life.
This type of control can be useful for fire-type effects (for example, the flame may start blue,
turn orange, and end a darker red). The gradient itself can be animated over time by right-
clicking on the control and selecting Animate from the contextual menu. All points on the
gradient will be controlled by a single Color Over Life spline, which controls the speed at which
the gradient itself changes. You may also use the From Image modifier, which produces a
gradient from the range of colors in an image along a line between two points.
Particles Size and Fade Controls
Size Controls
The majority of the Size Controls are self-explanatory. The Size and Size Variance controls are
used to determine the size and degree of size variation for each particle. It is worth noting that
the Point style does not have size controls (each point is a single pixel in size, and there is no
additional control).
When a Bitmap Particle style is used, a value of 1.0 indicates that each particle should be the
same size as the input bitmap. A value of 2.0 will scale the particle up in size by 200%. For the
best quality particles, always try to make the input bitmap as big, or bigger, than the largest
particle produced by the system.
For the Point Cluster style, the size control adjusts the density of the cluster, or how close
together each particle will get.
There are additional size controls that can be used to adjust further the size of particles based
on velocity and depth.
Size to Velocity
This increases the size of each particle relative to the velocity or speed of the particle. The
velocity of the particle is added to the size, scaled by the value of this control.
1.0 on this control, such as for a particle traveling at 0.1, will add another 0.1 to the size (velocity *
size to velocity + size = new size). This is most useful for Line styles, but the control can be used
to adjust the size of any style.
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