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Parameters in this section determine the nature of each exported particle.
Particle Radius
By default, Cinema particles are exported as analytical spheres using the MaxwellParticles Extension. For Particle Emitters, exported spheres are one export unit in radius, modulated by the object's End Scale and Scale Variation values, with the tag's Particle Radius value being used to scale the particle cloud globally (this uses the MaxwellParticles Radius Factor parameter). For Particle Geometry objects, the size of each sphere is determined by the Size value of each individual particle (the Size parameter in PStorm, for example), where 1.0 means 1.0 export unit. The entire group will then be scaled using the Particle Radius value.
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Several different arrays of data may be involved in rendering particles. Since it is desirable to keep memory usage to a minimum, the following options are provided, for the purpose of loading the various arrays of data selectively. Several of the arrays also have a related Channel ID; if during export, an array is enabled, then custom UVs will be generated for the particle cloud, on the specified texture channel.
Particle Radius
Since Particle Emitters do not output particles of differing size, this option will have no effect on them. Particle Geometries may export differing particle size, though, so if you want this information to be reflected in the export, be sure to enable this option. When exporting clones, be aware that the Scale with radius option will have no effect, unless Particle Radius loading is enabled.
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The Maxwell particles system can optionally generate extra particles for each particle defined in Cinema. The Quantity value simply specifies how many extra particles to generate. The Dispersion and Deformation parameters control how the cloud of extra particles is generated. Dispersion sets the size of the cloud of extra particles, around each exported particle. Deformation sets the amount of deformation of the new particles cloud along the speed vector of the original particle. Note that in order to achieve good results, the Particle ID array needs to be exported when using this feature.