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With this parameter you determine the global size of the particles in the rendered image. If you want to scale the particles based on certain channels like velocity or age please take a look at the “Particle Size” panels.
Radius PP
When you enable this feature, the radius value will be read from the loaded particle files. “PP” stands for “Per Particle”This feature is only available with RPC files with a radius value, e.g. from HySPH splash emitters. When a splash particle is created its radius is 1.0. This radius decreases over time and turns to 0 when the particle is dying. The appropriate "Radius PP" value is then multiplied with the "Radius" parameter.
Core/Splash
The idea behind this parameter is to separate the fluid into a core fluid and a splash part. With Hybrido simulations this feature is certainly not of significant importance, because there you have the possibility of adding splashes and foam as separate passes with great accuracy. For standard particle simulations, on the other hand, it is a quick way to split the particles:
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