The Particle Size attributes set particle radius. You can use the Radius Scale ramp to map radius on a per-particle basis using nParticle attributes, such as Lifespan, Color, and Mass, as the ramp's input values.
- Radius
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Radius of individual particles belonging to the nParticle object. The Radius setting provides the input value for the Radius Scale ramp.
Radius Scale
Lets you set per-particle radius based on the Radius attribute value. On the ramp, the vertical component represents values from 0 (no radius) to 1 (equal to the Radius attribute value). See Set attributes using ramps.
If the Radius Scale Input is set to Off, the per-particle attributes are deleted. If it is set to any other value, the radius per-particle attributes are created if they don’t already exist.
Radius Scale Input
Specifies which attribute is used to map the Radius Scale ramp values.
- Off
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When off, the per-particle attributes are deleted. If you want to use an expression with the per-particle attribute, you need to manually add them again. See About nParticle internal ramps and per-particle attributes.
- Age
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The per-particle attribute values are determined by the nParticle’s age, which is based on the particle Lifespan mode. See nParticle Lifespan attributes.
- Normalized Age
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The per-particle attribute values are determined by the normalized age of the nParticle. To use Normalized Age, the nParticle object must have a defined lifespan. For example, the nParticle object’s Lifespan Mode attribute must be set to Constant or Random range.
When Normalized Age is used, The per-particle attribute values are mapped within the range of the nParticle object’s lifespan.
- Speed
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The per-particle attribute values are determined by nParticle speed.
- Acceleration
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The per-particle attribute values are determined by nParticle acceleration.
- Particle ID
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The per-particle attribute values are determined by the nParticle’s ID. Particle IDs are unique and generated at the beginning of the particle’s lifespan.
- Randomizing ID
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The per-particle attribute values are determined by a randomized nParticle ID.
- Input Max
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Sets the maximum value for the range used by the ramp.
- Radius Scale Randomize
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Sets a random multiplier for the per-particle attribute values.