For particle systems,
Push applies a uniform, unidirectional force. For dynamics systems,
it provides a point force: like pushing something with your finger.
Push disperses a cloud
The Push space warp applies
a force to either
systems. The effect is different, depending
on the system:
- Particles: Applies
a uniform, unidirectional force in a positive or negative direction.
A positive force moves in the direction of the pad on the hydraulic
jack. The breadth of the force is infinite, perpendicular to the
direction; you can limit it using the Range option.
- Dynamics: Provides
a point force (also called a point load) away from the pad of the
hydraulic jack icon. A negative force pulls in the opposite direction.
In dynamics, applying a force is the same as pushing something with
Push viewport icon
To create a Push space warp:
- On the Create
panel, click (Space Warps).
Choose Forces from the list, then on the Object Type rollout, click Push.
- Drag in a viewport to define the size.
The Push warp appears
as a hydraulic jack icon.
- On Time/Off Time
The numbers of the frames
in which the space warp begins and ends its effect. Because Push
moves the particles to which it's applied over time, no keyframes
Strength Control group
- Basic Force
The amount of force exerted
by the space warp.
This option specifies
the units of force used by the Basic Force spinner.
A pound is about 4.5
Newtons, and one newton is one kilogram-per-second-squared. When
Push is applied to particle systems, these values have only subjective
meaning because they depend on the built-in weighting factors and
time scaling used by the particle system. However, when used in
a dynamics system, the value listed is precisely the value used.
- Feedback On
When on, the force varies depending
on the speed of the affected particles relative to the specified
Target Speed. When off, the force remains constant, regardless of
the speed of the affected particles.
When on, if the particle's speed
exceeds the Target Speed setting, the force is reversed. Available
only if you turn on Feedback On.
- Target Speed
Specifies the maximum speed
in units per frame before the Feedback takes effect. Available only
if you turn on Feedback On.
Specifies how quickly
the force adjusts to approaching the target speed. If set to 100
percent, the correction is immediate. If set lower, a slower and
"looser" response occurs. Available only if you turn on Feedback On.
NoteSetting Gain above
100 percent can result in over-correction, but is sometimes necessary
to overcome damping from other system settings, such as IK damping.
Periodic Variation group
These settings introduce
variations into the force by affecting the Basic Force value randomly.
You can set two waveforms to produce a noise effect.
- Period 1
The time over which the noise
variation makes a full cycle. For example, a setting of 20 means
one cycle per 20 frames.
- Amplitude 1
The strength of the variation
(in percent). This option uses the same types of units as the Basic
- Phase 1
Offsets the variation pattern.
- Period 2
Provides an additional variation
pattern (a second wave) to increase the noise.
- Amplitude 2
The strength of the variation
of the second wave (in percent). This option uses the same types
of units as the Basic Force spinner.
- Phase 2
Offsets the variation pattern
of the second wave.
Particle Effect Range group
Lets you restrict the
Push effect's range to a specific volume. This affects particle
systems only; it has no effect on dynamics.
When on, limits the range
of the effect to a sphere, displayed as a tri-hooped sphere. The
effect falls off increasingly as the particles near the boundary
of the sphere.
Specifies the radius
of the range of the effect, in units.
Display Icon group
- Icon Size
Sets the size of the
Push icon. This is for display purposes only, and does not alter
the Push effect.