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The magnitude of the referenced force determines the how much the force attracts or repels the particles, but it interacts with the mass and charge attributes of the particles (if a particle is negatively charged the effect of this operator is reversed), unless you use the Ignore charge and Ignore mass options.
To apply a global force to particles, use the Force POP.
You can use a SOP connected to one of the POP networks inputs as the attractor, or reference an arbitrary SOP, according to the Attractor use parameter on the Attractor tab.
Using an input gives you the flexibility to easily change which geometry to use for the attractor, either manually or programatically.
Using an explicit reference is useful when the attractor geometry is in a known location and is not expected to change.
This force is similar to the Follow POP. This tool should be used when you want to attract particles to a static object, whereas the follow tool should be used when you want to attract particles to a moving object.
This operator modifies the
Turns this node on and off. The node is only active if this value is greater than 0. This is useful to control the effect of this node with an expression.
Note that this is activation of the node as a whole. You can’t use this parameter to deactivate the node for certain particles.
How the points of the attractor affect the input particles.
All points affect each particle.
Single point per particle
Only one point affects each particle. The
attribute controls. Use the Property
POP to set the attractor-related
attribute on particles.
Specifies the SOP to use.
Use Parameter Values
Use the SOP specified in the SOP parameter below.
Use First Context Geometry
Use the SOP connected to the POP network’s first input.
Use Second Context Geometry
Use the SOP connected to the POP network’s second input.
Use Third Context Geometry
Use the SOP connected to the POP network’s third input.
Use Fourth Context Geometry
Use the SOP connected to the POP network’s fourth input.
Path to the SOP (when Geometry source is set to Use Parameter Values).
Ignore Transform Object
Particles normally use the object space of the SOP being cooked. Turn this parameter on to not transform into the space of the cooking SOP.
Stop At Attractor
Particles stop when they reach the attractor.
Multiplies or divides the force of the attractor.
Show attractor radius in guide
Shows the radius of the force as part of the node’s guide geometry. Turn on the node’s template flag to see the guides.
Show acceleration in guide
Shows the applied acceleration as part of the node’s guide geometry. Turn on the node’s template flag to see the guides.
Ignores any charge attributes on the input particles.
Replaces any charge attributes on the input particles with the value of the Charge parameter below.
Charge to use when Override charge is on.
Ignores any mass attributes on the input particles.
Replaces any mass attributes on the input particles with the value of the Mass parameter below.
Mass to use when Override mass is on.
The parameters on this tab add randomness to the attraction force. This makes particles more or less attracted at random, creating a less uniform effect.
Seed value for the random turbulence generator.
Number of iterations of fractal noise to add.
Scale of noise added with each iteration.
Noise attenuation exponent.
Spatial frequency of noise field in X, Y, and Z.
Maximum value of noise field.
Amount to shift noise along X, Y, and Z axes.
Method used to generate noise. Hermite Interpolation and Improved Hermite are fastest.
Uses splines to interpolate values in the noise field.
More computationally expensive, but produces noise fields free of artifacts present in the Hermite methods.
Uses a more linear interpolation than Hermite interpolation.
Provides a very different look than the other noise types.
Standard POP local variables
The seconds a particle in the template has been alive.
AX AY AZ
Acceleration of the particle.
BBX BBY BBZ
The point’s relative position in the bounding box.
Point is dead.
Processing iteration number.
A collision for this particle was detected (for example, by the Collision POP) during the processing of this timestep (that is, this iteration of the particle simulation). This variable is cleared at the beginning of each timestep. Note that the collision POP actually detects any collisions which would have occurred the during the previous frame.
Percent of total life used (from 0 to 1).
Expected lifetime of particle.
MAPU MAPV MAPW
Point or vertex texture coordinates.
Total number of points.
Total number of points in source group.
NX NY NZ
The point number of the currently processed point. The
PT is not constant like
ID; it changes based on the number of points.
RESTX RESTY RESTZ
The rest position.
The sliding state of the particle.
Elasticity of a point.
Point is stopped.
1 if particle is stuck to a collision object.
TX TY TZ
Surface UV values.
VX VY VZ
Point spline weight.
Distance from particle to last collision.
HCR HCG HCB
Diffuse color at the collision point on the surface the particle collided with.
ID for last collision. You can control how this attribute is set in the Collision or Limit POP to help distinguish types of collisions.
The time at which the last collision occurred.
The texture map UV coordinates for the surface location where the last collision occurred.
HNX HNY HNZ
The normal at the surface location where the last collision occurred.
HTX HTY HTZ
World space position of the last collision.
The UV coordinates for the surface location where the last collision occurred.
Number of times the particle has collided.
Added by Color POP
Point or vertex alpha value.
CR CG CB
Diffuse point or vertex color.
Added by Property POP
Charge of the particle.
Point is clinging to geometry.
Leader to follow.
SCALEX SCALEY SCALEZ
Added by Proximity POP
Either the point number or id of the particle nearest to this one.
The distance to the nearest particle.
The number of particles within a specified proximity to this particle.
Added by Rotation POP
ROTX ROTY ROTZ
Added by Source POP
ID number, which always remains constant.
Original Source point was birthed from.
Parent’s ID Number.
Added by Speed Limit POP
Added by Sprite POP
Sprite rotation around view axis (in degrees).
Texture coordinate of sprite’s lower-left corner.
Size of sprite in texture space.
Controlled by Suppress Rule POP
Suppress default position rule.
Suppress default velocity rule.
Suppress default up-vector rule.
Suppress default aging rule.
1 if particle is suppressing its default rotation rule.
1 if particle is suppressing its default angular velocity rule.
Added by Up Vector POP
PVX PVY PVZ
UPX UPY UPZ
Absolute speed of particle.