The parameters on the
Setup rollout determine the density and placement of particle seeds
as well as stroke timing.
ImportantFor these parameters
to affect the strokes or seeds, you must set them before you
create particle seeds. Changing values after creating particle seeds
has no effect on the existing strokes or seeds.
- Freehand Paint
Activates a freehand paint
tool, allowing you to drag anywhere in an orthographic viewport
to set particle seeds. The timing of the drag across an object determines
the base timing for particle birth when used with the Birth Paint or
Particle Paint operators. This option is available only on the Modify
ImportantTo use the freehand
paint tool, you must work from one of the orthographic viewports
such as Top or Front. You cannot use this tool in Perspective, Camera,
or Spotlight viewports.
Each time you release
the mouse while using this tool, you create an individual stroke. You
can create as many strokes as you like for each Particle Paint helper.
Particle timing and other options for each stroke are governed by the
other settings on the Setup rollout.
To stop creating strokes,
right-click in the active viewport or click the Freehand Paint button again.
- Pick Stroke Spline
Allows you to pick one
or more standard splines as paths for the particle seeds. Particles
are then placed along this spline, but are projected on to 3D surfaces
into the orthogonal viewport. The splines do not have to be in front
of the surfaces in the orthographic viewport; Particle Paint will
project from splines to surfaces as if the splines were in front
of the objects regardless of their actual positions in 3D space.
The picked splines can
be either open or closed splines. NURBS curves cannot be used as
You can pick as many
splines as you like, and each spline picked is considered to be
a separate stroke. The stroke starts from the spline's first vertex,
and continues along the spline until it reaches the end of the spline
(or the first vertex, in the case of closed splines).
- Total Particle Seeds
The total number of particle
seeds that have been generated.
The number of strokes created
by the Particle Paint helper.
- Brush Radius
Adjusts the spray emitter's
nozzle size. The change in size is reflected in the Particle Paint
icon. This value determines the distance around the center of the
nozzle by which particle seeds spread when using either method to
generate particle seeds. This value can be animated over time.
Paint Density group
These controls set the
particle seeds' area of distribution within the emitter nozzle.
- Center (%)
Percentage of particle seeds
that spray at the center of the nozzle.
- Sides (%)
Percentage of particle seeds
that spray at the edges of the nozzle. Higher percentages result
in wider bands of particles.
Paint Flow Rate group
These controls determine
how many particle seeds are emitted and how fast they are emitted
over the course of a single stroke. For the freehand paint method,
a stroke is defined by the time you press the mouse button to start
the stroke, until you release the mouse button. For a spline, one
stroke is distributed over each spline picked.
- Stroke Limit
Sets the overall number of
particle seeds that can be emitted per stroke when using the freehand
or spline methods. So if Seeds p/sec is 25.0 and Stroke Limit is
100.0, you can spray for four seconds before running out of particle
seeds with that one stroke. This parameter is overridden by the
Stroke spray rate type, selected under Type (see following).
Sets the spray rate type. The
available choices are Time, Length, and Stroke. Each one works with
one of the later parameters to set the spray rate.
the spray rate by particle seeds per second.
- LengthSets the
spray rate by spatial movement of the nozzle.
- StrokeSets the
spray rate with a specific number of particle seeds per stroke,
regardless of stroke length. This option overrides the Stroke Limit
parameter (see preceding).
- [rate value]
Depending on the Type setting
(see preceding), one of these is available to set the number of
seeds created when painting.
- Seeds p/secThe
number of particle seeds emitted per second as you draw in viewports. Higher
values cause more seeds to be emitted. This option is available
only for the Time spray rate type (see preceding).
- Paint StepThe
distance the nozzle center must move between emitting individual
particle seeds. Higher values cause fewer seeds to be emitted during
a stroke. This option is available only for the Length spray rate
- Total AmountDetermines
the total number of particle seeds per stroke, regardless of the
stroke length in units or time. Seeds are evenly distributed over
the stroke time. This option is available only for the Stroke spray
Brush Adjustment group
These controls are used
for fine-tuning the Brush Radius and Flow Rate with regard to stroke
Provides for varying
the seed-painting radius over the course of each stroke. Alternatively,
you can animate the Brush Radius parameter to vary the brush size,
but that animation occurs in absolute time (that is, within a specific
frame range). Use this option to adjust the brush radius within
a single stroke regardless of its start and end times.
Clicking Radius opens
Brush Radius Graph (Particle Paint).
The settings on the graph are in effect when the Radius option is on.
Provides for varying
the seed-painting rate over the course of each stroke. Alternatively,
you can animate the Seeds p/sec parameter to vary the rate, but
this animates the rate in absolute time (that is, within a specific
frame range). Use the Rate option to adjust the seed painting rate
within a single stroke regardless of its start and end times.
Clicking Rate displays
Paint Flow Rate Graph (Particle Paint).
The settings on the graph are in effect when the Rate option is on.
- Display Type
This drop-down list gives you
the choice of how to display the particles in the viewports. You
can choose Ticks or Flags as the display type. The Flags type gives
more information about each seed’s rotational data. The pole of
a flag marker is aligned with its seed’s local Z axis, while the
banner points in the direction of the local X axis.
- Particle Size
Sets the size of the
flag markers. Available for the Flags type only.
Stroke Start group
The settings in this
group determine the start frame for particle seeds generated by
a stroke. These timing values can be used later by the
Placement Paint operators
for precise timing of every particle emitted.
- Stroke Start
Choose either of the following:
- Current FrameStarts
the stroke timing at the current frame.
- FixedStarts the
stroke timing at the indicated frame.
Stroke Stop group
These settings specify
the method for determining the duration or stop frame of the stroke.
- Stroke Stop
Choose one of the following:
- Real-Time OffsetDefines
stroke time by the actual time taken for drawing the stroke. If you
created a stroke by picking a spline, then the default time for
the stroke is one second.
Use the Time Scale %
parameter to define the correspondence between the animation time
(frames of animation) and the real-world time when a stroke is drawn.
For example, a value of 100.0 means that one second of actual time
corresponds to 30 frames of animation (for NTSC), while a value
of 50.0 means that one second of stroke drawing corresponds to 15
frames of animation.
Adjusting the Time
Scale % value changes the effective flow rate of the painting, since
uses animation time, not drawing time.
- FixedStops the
stroke at the specified frame, in absolute time.
the stroke length in frames.
- Auto Adjust Current Frame
Aligns the start of each successive
stroke automatically with the stop time of the previous one. If
you turn on this option for an exsisting stroke, the time slider
is adjusted to the stop moment of the stroke. This option is available
only if Stroke Start is set to Current Frame and Stroke Stop is
set to either Real-Time Offset or Duration.
- Auto Adjust Global Timing
Adjusts emission timing of
the related Birth Paint operator automatically.
The Birth Paint operator
has its own parameters that define when particles start and stop
emission. When this switch is off, Particle Flow fits the timing
of the strokes into the Birth Paint operator’s Start/Stop interval.
However, when this option is on, Particle Paint allows the related
Birth Paint operator to adjust its emission timing to the timing
of the strokes.
- Icon Size
Adjusts the overall size
of the helper icon, but does not affect the nozzle radius.
Paint Spread Uniqueness
These settings randomize
particle-seed distribution over a stroke. If you pick the same spline
for a stroke, the helper generates the same placement for seeds.
To generate varied particle placement for the same spline, change
the Seed value.
Specifies a randomization
value. Not otherwise related to particle seeds.
Generates a new Seed value.