The Path Follow operator allows you to apply forces to particles using regular shapes and splines.

#### Shapes

• Shape object list: the list of input shape objects.

#### Shape

• Closest/Random: defines which shape to follow from the list.

#### Follow

Follow forces are forces that are parallel to shape tangents.

• Velocity:: the value of the force applied to particles.

• Variation %: the per-particle percentage of variation to apply.
• Falloff: the distance over which forces will be diminished, according to the inverse-square law. A value of 0 means no falloff will be computed.

• Accel %: controls how quickly particle forces will accelerate from their old values to the newly applied values.

#### Attraction

Attraction forces are forces that are perpendicular to shape tangents, which cause particles to move toward shapes.

• Velocity:: the value of the force applied to particles.

• Variation %: the per-particle percentage of variation to apply.
• Falloff: the distance over which forces will be diminished, according to the inverse-square law. A value of 0 means no falloff will be computed.

• Accel %: controls how quickly particle forces will accelerate from their old values to the newly applied values.
• Clamp to distance: when enabled, the length of the attraction velocity vector will not exceed the distance from a particle to the target spline. This prevents velocity overshoot.

#### Spin

Spin forces are forces that are perpendicular to shape tangents, which cause particles to move around shapes.

• Velocity:: the value of the force applied to particles.

• Variation %: the per-particle percentage of variation to apply.
• Falloff: the distance over which forces will be diminished, according to the inverse-square law. A value of 0 means no falloff will be computed.

• Accel %: controls how quickly particle forces will accelerate from their old values to the newly applied values.

#### Distance to shape

• Dynamic: no constraints are placed on the distance particles are allowed to travel towards/away from input shapes.

• Locked the initial distance any given particle is to an input shape, is the exact distance they must maintain while affected by the operator.

• Initial distance is min distance the initial distance any given particle is to an input shape, is the minimum distance they must maintain while affected by the operator. Particles are allowed to travel further than that distance away from the input shapes.

• Initial distance is max distance the initial distance any given particle is to an input shape, is the maximum distance they must maintain while affected by the operator. Particles are allowed to travel closer than that distance towards the input shapes.

• Custom min/max: the range of distances a particle must stay within, from input shapes, is defined by the user.

• Min/Max: the range of distances used in ‘Custom min/max’ mode”

#### Settings

• Spline interp: the number of sub-segments to slice input shapes up into, which will be used to accelerate the shape proximity algorithm.
• Lock to first shape: controls whether particles will continually look for a new shape to derive their forces from, or if they’ll stay locked to the same shape for their entire stay within the event.

• Relative to mass: controls whether particle forces will be relative to particle masses.

• Simulate substeps: forces will be interpolated in a way that simulates the addition of forces at smaller simulation substeps.

#### Uniqueness

• Seed: the seed value for all varied parameters.